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Posted to dev@cloudstack.apache.org by David Nalley <da...@gnsa.us> on 2012/10/20 00:47:01 UTC
Re: git commit: Architecture refactoring - Stateless management
server - Spring Framework initiatives
This adds a number of new dependencies.
This needs to explicitly be discussed before it gets committed.
See below for reference:
http://markmail.org/message/huevw4ur73a64b5c
On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
> Updated Branches:
> refs/heads/javelin a75916d45 -> 8ef9e32cf
>
>
> Architecture refactoring - Stateless management server - Spring Framework initiatives
>
>
> Project: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
> Commit: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef9e32c
> Tree: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e32c
> Diff: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e32c
>
> Branch: refs/heads/javelin
> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
> Parents: a75916d
> Author: Kelven Yang <ke...@citrix.com>
> Authored: Fri Oct 19 15:24:01 2012 -0700
> Committer: Kelven Yang <ke...@citrix.com>
> Committed: Fri Oct 19 15:24:15 2012 -0700
>
> ----------------------------------------------------------------------
> client/WEB-INF/web.xml | 9 ++-
> pom.xml | 81 +++++++++++++++
> utils/conf/db.properties | 1 +
> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
> 6 files changed, 99 insertions(+), 5 deletions(-)
> ----------------------------------------------------------------------
>
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/client/WEB-INF/web.xml
> ----------------------------------------------------------------------
> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
> index 50f2455..c6fd30f 100644
> --- a/client/WEB-INF/web.xml
> +++ b/client/WEB-INF/web.xml
> @@ -20,7 +20,14 @@
> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
> version="2.5">
>
> -
> + <listener>
> + <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
> + </listener>
> + <context-param>
> + <param-name>contextConfigLocation</param-name>
> + <param-value>classpath:applicationContext.xml</param-value>
> + </context-param>
> +
> <servlet>
> <servlet-name>cloudStartupServlet</servlet-name>
> <servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/pom.xml
> ----------------------------------------------------------------------
> diff --git a/pom.xml b/pom.xml
> index 3c14d4e..5f63ce6 100644
> --- a/pom.xml
> +++ b/pom.xml
> @@ -79,6 +79,7 @@
> <cs.servlet.version>2.4</cs.servlet.version>
> <cs.jstl.version>1.2</cs.jstl.version>
> <cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.version>
> + <org.springframework.version>3.0.5.RELEASE</org.springframework.version>
> <skipTests>true</skipTests>
>
> </properties>
> @@ -169,6 +170,86 @@
> <version>${cs.junit.version}</version>
> <scope>test</scope>
> </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-core</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-expression</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-beans</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-aop</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-context</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-context-support</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-tx</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-jdbc</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-orm</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-oxm</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-web</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-webmvc</artifactId>
> + <version>${org.springframework.version}</version>
> + </dependency>
> +
> + <dependency>
> + <groupId>org.springframework</groupId>
> + <artifactId>spring-test</artifactId>
> + <version>${org.springframework.version}</version>
> + <scope>test</scope>
> + </dependency>
> +
> </dependencies>
>
> <build>
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/utils/conf/db.properties
> ----------------------------------------------------------------------
> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
> index 6bdb6d6..8d98119 100644
> --- a/utils/conf/db.properties
> +++ b/utils/conf/db.properties
> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
> # CloudStack database settings
> db.cloud.username=cloud
> db.cloud.password=cloud
> +db.root.password=
> db.cloud.host=localhost
> db.cloud.port=3306
> db.cloud.name=cloud
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/utils/src/com/cloud/utils/events/EventBus.java
> ----------------------------------------------------------------------
> diff --git a/utils/src/com/cloud/utils/events/EventBus.java b/utils/src/com/cloud/utils/events/EventBus.java
> index 4195acd..c1b6f70 100644
> --- a/utils/src/com/cloud/utils/events/EventBus.java
> +++ b/utils/src/com/cloud/utils/events/EventBus.java
> @@ -17,9 +17,11 @@
>
> package com.cloud.utils.events;
>
> +import java.io.Serializable;
> +
> public interface EventBus {
> void subscribe(String subject, Subscriber subscriber);
> void unsubscribe(String subject, Subscriber subscriber);
>
> - void publish(String subject, PublishScope scope, Object sender, String args);
> + void publish(String subject, PublishScope scope, Object sender, Serializable args);
> }
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/utils/src/com/cloud/utils/events/EventBusBase.java
> ----------------------------------------------------------------------
> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java b/utils/src/com/cloud/utils/events/EventBusBase.java
> index 0c135db..cd10f1d 100644
> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
> @@ -17,6 +17,7 @@
>
> package com.cloud.utils.events;
>
> +import java.io.Serializable;
> import java.util.ArrayList;
> import java.util.HashMap;
> import java.util.List;
> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
>
> @Override
> public void publish(String subject, PublishScope scope, Object sender,
> - String args) {
> + Serializable args) {
>
> if(_gate.enter(true)) {
>
> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
> _children.put(key, childNode);
> }
>
> - public void notifySubscribers(String subject, Object sender, String args) {
> + public void notifySubscribers(String subject, Object sender, Serializable args) {
> for(Subscriber subscriber : _subscribers) {
> subscriber.onPublishEvent(subject, sender, args);
> }
>
> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c/utils/src/com/cloud/utils/events/Subscriber.java
> ----------------------------------------------------------------------
> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java b/utils/src/com/cloud/utils/events/Subscriber.java
> index 7af283b..c3baa6f 100644
> --- a/utils/src/com/cloud/utils/events/Subscriber.java
> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
> @@ -17,6 +17,8 @@
>
> package com.cloud.utils.events;
>
> +import java.io.Serializable;
> +
> public interface Subscriber {
> - void onPublishEvent(String subject, Object sender, String args);
> + void onPublishEvent(String subject, Object sender, Serializable args);
> }
>
RE: who can give documents of cloudstack-databases design and implements?
Posted by "Kelcey Damage (BBITS)" <ke...@bbits.ca>.
Here is a very rudimentary guide for 3.0.2, however its only partially complete:
Old wiki
http://wiki.cloudstack.org/download/attachments/2064409/db-resource.pdf
KELCEY DAMAGE
Infrastructure Systems Architect
www.backbonetechnology.com
-------------------------------------------------------------------------
kelcey@bbits.ca
address: 55 East 7th Ave, Vancouver, BC, V5T 1M4
tel: +1 604 713 8560 ext:114
fax: +1 604 605 0964
skype: kelcey.damage
-----Original Message-----
From: coudstacks [mailto:cloudstacks@163.com]
Sent: Saturday, October 20, 2012 7:11 AM
To: cloudstack-dev@incubator.apache.org
Subject: who can give documents of cloudstack-databases design and implements?
who can give documents of cloudstack-databases design and implements?
i want to know databases part deeper.
thanks
who can give documents of cloudstack-databases design and
implements?
Posted by coudstacks <cl...@163.com>.
who can give documents of cloudstack-databases design and implements?
i want to know databases part deeper.
thanks
RE: [DISCUSS] git commit: Architecture refactoring - Stateless
management server - Spring Framework initiatives
Posted by Edison Su <Ed...@citrix.com>.
> -----Original Message-----
> From: Kelven Yang [mailto:kelven.yang@citrix.com]
> Sent: Monday, November 12, 2012 1:31 PM
> To: cloudstack-dev@incubator.apache.org
> Subject: Re: [DISCUSS] git commit: Architecture refactoring - Stateless
> management server - Spring Framework initiatives
>
>
> On 11/12/12 10:58 AM, "Chip Childers" <ch...@sungard.com> wrote:
>
> >On Thu, Nov 8, 2012 at 7:19 PM, Kelven Yang <ke...@citrix.com>
> >wrote:
> >>
> >> As part of architecture refactoring work, we are exploring some
> >>initiatives that would help CloudStack move toward more
> >>component-based architecture, one of such efforts is to standardize
> >>the way on how a single individual java component to be integrated
> >>into CloudStack system.
> >>
> >> CloudStack currently uses ComponentLocator to bootstrap components,
> >>it has done a great job while in the mean time, there are a couple of
> >>issues with this customized component injection framework (in my
> >>view).
> >>
> >> 1) ComponentLocator can not fully perform dependency injection, it
> >>can inject independent components without a problem, however, when
> >>things come with dependency, it will become tricky, although most of
> >>time auto-wiring with @Inject annotation works, but in some other
> >>time, developers will have to use following explicit wiring logic to
> >>make things work.
> >>
> >> @Local(value={UsageManager.class})
> >> public class UsageManagerImpl implements UsageManager, Runnable {
> >> public static final Logger s_logger =
> >> Logger.getLogger(UsageManagerImpl.class.getName());
> >>
> >> protected static final String DAILY = "DAILY";
> >> protected static final String WEEKLY = "WEEKLY";
> >> protected static final String MONTHLY = "MONTHLY";
> >>
> >> private static final int HOURLY_TIME = 60;
> >> private static final int DAILY_TIME = 60 * 24;
> >> private static final int THREE_DAYS_IN_MINUTES = 60 * 24 * 3;
> >> private static final int USAGE_AGGREGATION_RANGE_MIN = 10;
> >>
> >> --> hard-wiring logic goes here...
> >> private final ComponentLocator _locator =
> >>ComponentLocator.getLocator(UsageServer.Name, "usage-
> components.xml",
> >>"log4j-cloud_usage");
> >> private final AccountDao m_accountDao =
> >>_locator.getDao(AccountDao.class);
> >> private final UserStatisticsDao m_userStatsDao =
> >>_locator.getDao(UserStatisticsDao.class);
> >> private final UsageDao m_usageDao =
> _locator.getDao(UsageDao.class);
> >> private final UsageVMInstanceDao m_usageInstanceDao =
> >>_locator.getDao(UsageVMInstanceDao.class);
> >> private final UsageIPAddressDao m_usageIPAddressDao =
> >>_locator.getDao(UsageIPAddressDao.class);
> >> private final UsageNetworkDao m_usageNetworkDao =
> >>_locator.getDao(UsageNetworkDao.class);
> >> private final UsageVolumeDao m_usageVolumeDao =
> >>_locator.getDao(UsageVolumeDao.class);
> >> private final UsageStorageDao m_usageStorageDao =
> >>_locator.getDao(UsageStorageDao.class);
> >> private final UsageLoadBalancerPolicyDao
> >>m_usageLoadBalancerPolicyDao =
> >>_locator.getDao(UsageLoadBalancerPolicyDao.class);
> >> private final UsagePortForwardingRuleDao
> >>m_usagePortForwardingRuleDao =
> >>_locator.getDao(UsagePortForwardingRuleDao.class);
> >> private final UsageNetworkOfferingDao m_usageNetworkOfferingDao
> =
> >>_locator.getDao(UsageNetworkOfferingDao.class);
> >> private final UsageVPNUserDao m_usageVPNUserDao =
> >>_locator.getDao(UsageVPNUserDao.class);
> >> private final UsageSecurityGroupDao m_usageSecurityGroupDao =
> >>_locator.getDao(UsageSecurityGroupDao.class);
> >> private final UsageJobDao m_usageJobDao =
> >>_locator.getDao(UsageJobDao.class);
> >>
> >> The problem of doing so is that we create a cross-reference between
> >>component and the component container, it breaks the principle of
> >>being component-ized. In the above case, the component shouldn't
> >>really make any assumption of its container, and the other problem is
> >>that developers will sometimes be confused at when, under what
> >>situation, they can use @Inject to wire a component or they have to
> >>use run-time wiring logic like above to make it work.
> >>
> >>
> >> 2) AOP pattern is implicitly buried with current injection framework.
> >>
> >> AOP(Aspect Oriented Pattern) is very powerful concept, and CloudStack
> >>uses it a lot, @DB annotation is a very typical example. However,
> >>wiring an aspect is not that explicit, it buries inside those
> >>interceptors that work together with ComponentLocator during
> >>injection phase. Although AOP concept is powerful, but it better to
> >>be explicit, we need to encourage to component-ize the AOP aspect
> >>itself as component, although ComponentLocator has no problem to
> >>offer AOP support, it lacks of letting people do it in a more
> >>explicit way.
> >>
> >> 3) Unit test integration
> >> In the example in 1), to perform a unit test on the component, it
> >>involves with having to construct a mocked ComponentLocator, these
> >>little pieces add up to make unit-testing a little challenge in
> >>CloudStack.
> >>
> >
> >+1 - this is problematic
> >
> >>
> >> 4) CloudStack specific logic
> >>
> >> ComponentLocator also has CloudStack specific assumptions on
> >>Adapters, Managers, PluggableService etc, this has to move up to the
> >>business layer and leave this underlying layer generic and clean, if
> >>in the future people want to add some other cool stuff like
> >>CoolServiceGates etc, it requires the developer to modify
> >>ComponentLocator, this kind of possibility alone makes
> >>ComponentLocator itself not really a component, we should not
> >>encourage that.
> >>
> >> As a solution, we are exploring the possibility to adopt Spring
> >>Framework into CloudStack, it has the ability to address all above
> >>issues, the goal here is to leave all these generic concerns away
> >>from CloudStack core business logic, and standardize the way we
> >>program in CloudStack. The goal is
> >>
> >> 1) Individual component should be clean, no hard-coded assumption of
> >>any component container framework
> >> 2) System to in layered with clean boundary. No business logic leaked
> >>into generic plumbing layer.
> >> 3) AOP pattern to be explicit, represented through aspect component
> >>and explicit wiring of the AOP
> >> 4) Make unit test simple, simple and simple (Junit Spring integration
> >>has already done that)
> >>
> >
> >Great Goals...
> >
> >While Spring is an option, do you have any thoughts on Hugo's OSGi
> >suggestion?
>
>
>
> Our immediate focus right now is to first make interval component
> development easier, allow loosely coupled component to be integrated into
> CloudStack in a consistent and standard way. OSGi suggestion is a good one, I
> think once we have internally sliced CloudStack into a dozen of well
> encapsulated components, it will be a good option.
>
>
>
>
> >
> >Also, the AOP example you used relates to the persistence objects. On
> >a related note, do you consider it a reasonable goal to switch to a
> >non-custom JPA framework? IIRC, Hibernate isn't license compatible
> >(LGPL?). How about Apache's own OpenJPA
> ( http://openjpa.apache.org/ )?
>
> It is not that we are not considering of it, but just the amount of work and
> the priorities. Dependency Injection and Persistent framework by their own
> are separated projects and there are not many reasons for CloudStack not to
> use mature and popular ones so that we can focus on what we ought to. I
> personally prefer to see CloudStack going towards that direction, embrace
> some of the best from other communities and produce the best
> Orchestration Framework from our side.
>
> It will be easier to draw Java developers to CloudStack if the system looks
> familiar other than that he/she has to learn every single major plumbing
> work in order to get started. From this perspective, I support to go with other
> popular persist framework like openJPA, just not sure whether or not it is a
> good time. But in anyway, once Spring work is in place, switching to these
> alternatives will become much easier too.
I tried openjpa before, still have the same issue that Alex pointed out 2 years ago(http://mail-archives.apache.org/mod_mbox/openjpa-users/201011.mbox/%3CAANLkTimEG4Gi4Nx92pOzYZQdSyV3OaTGU6ayZwbA4B44@mail.gmail.com%3E), the openjpa integration with eclipse is not good at all.
>
>
> >
> >>
> >> Since 4.0 is already out of the door, I re-raise the discussion here
> >> again, please feel free to share your opinions
> >>
> >> Kelven
> >>
> >>
> >> On 10/19/12 6:14 PM, "Kelven Yang" <ke...@citrix.com> wrote:
> >>
> >> >David,
> >> >
> >> >Thanks for the remind. As we are working on a feature
> >> >branch(Javelin)
> >>and
> >> >thought not to heat-up the mailing list while everyone is still busy
> >> >on getting the 4.0 release out of the door.
> >> >
> >> >We are evaluating the possibility to leverage Spring Framework to
> >> >standardize Dependency injection/AOP pattern usages in CloudStack.
> >>Spring
> >> >framework is very popular to Java community and under Apache license.
> >>By
> >> >switching the underlying architecture plumbing to a de-facto
> >>standardized
> >> >framework would help attract developers to focus more on CloudStack
> >>core
> >> >business logic with already familiar coding practices.
> >> >
> >> >We will not extensively use full featured Spring Framework, may
> >>primarily
> >> >on core DI/AOP features since these are commonly used in CloudStack,
> >> >we also haven't decided to go with Spring annotation based approach
> >> >or XML based approach yet. With currently check-ins, they are
> >> >annotation based which I personally prefer, however, this may
> >> >change, depends on how to
> >>get
> >> >our old code loaded nicely under Spring.
> >> >
> >> >If anyone does have a strong opinion on this, please feel free to
> >> >share with us.
> >> >
> >> >
> >> >Kelven
> >> >
> >> >On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
> >> >
> >> >>This adds a number of new dependencies.
> >> >>
> >> >>This needs to explicitly be discussed before it gets committed.
> >> >>See below for reference:
> >> >>http://markmail.org/message/huevw4ur73a64b5c
> >> >>
> >> >>On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
> >> >>> Updated Branches:
> >> >>> refs/heads/javelin a75916d45 -> 8ef9e32cf
> >> >>>
> >> >>>
> >> >>> Architecture refactoring - Stateless management server - Spring
> >> >>>Framework initiatives
> >> >>>
> >> >>>
> >> >>> Project:
> >> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
> >> >>> Commit:
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-
> cloudstack/commit/
> >>>>>8ef
> >>>>>9e
> >> >>>3
> >> >>>2c
> >> >>> Tree:
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>> Diff:
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>
> >> >>> Branch: refs/heads/javelin
> >> >>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
> >> >>> Parents: a75916d
> >> >>> Author: Kelven Yang <ke...@citrix.com>
> >> >>> Authored: Fri Oct 19 15:24:01 2012 -0700
> >> >>> Committer: Kelven Yang <ke...@citrix.com>
> >> >>> Committed: Fri Oct 19 15:24:15 2012 -0700
> >> >>>
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> client/WEB-INF/web.xml | 9 ++-
> >> >>> pom.xml | 81
> >> >>>+++++++++++++++
> >> >>> utils/conf/db.properties | 1 +
> >> >>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
> >> >>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
> >> >>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
> >> >>> 6 files changed, 99 insertions(+), 5 deletions(-)
> >> >>>
> >>----------------------------------------------------------------------
> >> >>>
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/client/WEB-INF/web.xml
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
> >> >>> index 50f2455..c6fd30f 100644
> >> >>> --- a/client/WEB-INF/web.xml
> >> >>> +++ b/client/WEB-INF/web.xml
> >> >>> @@ -20,7 +20,14 @@
> >> >>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
> >> >>>http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
> >> >>> version="2.5">
> >> >>>
> >> >>> -
> >> >>> + <listener>
> >> >>> +
> >>
> >>>>><listener-
> class>org.springframework.web.context.ContextLoaderListen
> >>>>>er<
> >>>>>/l
> >> >>>i
> >> >>>stener-class>
> >> >>> + </listener>
> >> >>> + <context-param>
> >> >>> + <param-name>contextConfigLocation</param-name>
> >> >>> + <param-value>classpath:applicationContext.xml</param-
> value>
> >> >>> + </context-param>
> >> >>> +
> >> >>> <servlet>
> >> >>> <servlet-name>cloudStartupServlet</servlet-name>
> >> >>>
> >> >>><servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-clas
> >> >>>s>
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/pom.xml
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/pom.xml b/pom.xml
> >> >>> index 3c14d4e..5f63ce6 100644
> >> >>> --- a/pom.xml
> >> >>> +++ b/pom.xml
> >> >>> @@ -79,6 +79,7 @@
> >> >>> <cs.servlet.version>2.4</cs.servlet.version>
> >> >>> <cs.jstl.version>1.2</cs.jstl.version>
> >> >>>
> >>
> >>>>><cs.selenium.server.version>1.0-
> 20081010.060147</cs.selenium.server
> >>>>>.ve
> >>>>>rs
> >> >>>i
> >> >>>on>
> >> >>> +
> >>
> >>>>><org.springframework.version>3.0.5.RELEASE</org.springframework.
> ver
> >>>>>sio
> >>>>>n>
> >> >>> <skipTests>true</skipTests>
> >> >>>
> >> >>> </properties>
> >> >>> @@ -169,6 +170,86 @@
> >> >>> <version>${cs.junit.version}</version>
> >> >>> <scope>test</scope>
> >> >>> </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-core</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-expression</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-beans</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-aop</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-context</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-context-support</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-tx</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-jdbc</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-orm</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-oxm</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-web</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-webmvc</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + </dependency>
> >> >>> +
> >> >>> + <dependency>
> >> >>> + <groupId>org.springframework</groupId>
> >> >>> + <artifactId>spring-test</artifactId>
> >> >>> + <version>${org.springframework.version}</version>
> >> >>> + <scope>test</scope>
> >> >>> + </dependency>
> >> >>> +
> >> >>> </dependencies>
> >> >>>
> >> >>> <build>
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/utils/conf/db.properties
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
> >> >>> index 6bdb6d6..8d98119 100644
> >> >>> --- a/utils/conf/db.properties
> >> >>> +++ b/utils/conf/db.properties
> >> >>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090 # CloudStack
> >> >>> database settings db.cloud.username=cloud
> >> >>> db.cloud.password=cloud
> >> >>> +db.root.password=
> >> >>> db.cloud.host=localhost
> >> >>> db.cloud.port=3306
> >> >>> db.cloud.name=cloud
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/utils/src/com/cloud/utils/events/EventBus.java
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
> >> >>>b/utils/src/com/cloud/utils/events/EventBus.java
> >> >>> index 4195acd..c1b6f70 100644
> >> >>> --- a/utils/src/com/cloud/utils/events/EventBus.java
> >> >>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
> >> >>> @@ -17,9 +17,11 @@
> >> >>>
> >> >>> package com.cloud.utils.events;
> >> >>>
> >> >>> +import java.io.Serializable;
> >> >>> +
> >> >>> public interface EventBus {
> >> >>> void subscribe(String subject, Subscriber subscriber);
> >> >>> void unsubscribe(String subject, Subscriber subscriber);
> >> >>>
> >> >>> - void publish(String subject, PublishScope scope, Object
> >>sender,
> >> >>>String args);
> >> >>> + void publish(String subject, PublishScope scope, Object
> >>sender,
> >> >>>Serializable args);
> >> >>> }
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/utils/src/com/cloud/utils/events/EventBusBase.java
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
> >> >>>b/utils/src/com/cloud/utils/events/EventBusBase.java
> >> >>> index 0c135db..cd10f1d 100644
> >> >>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
> >> >>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
> >> >>> @@ -17,6 +17,7 @@
> >> >>>
> >> >>> package com.cloud.utils.events;
> >> >>>
> >> >>> +import java.io.Serializable;
> >> >>> import java.util.ArrayList;
> >> >>> import java.util.HashMap;
> >> >>> import java.util.List;
> >> >>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus
> {
> >> >>>
> >> >>> @Override
> >> >>> public void publish(String subject, PublishScope scope,
> >>Object
> >> >>>sender,
> >> >>> - String args) {
> >> >>> + Serializable args) {
> >> >>>
> >> >>> if(_gate.enter(true)) {
> >> >>>
> >> >>> @@ -283,7 +284,7 @@ public class EventBusBase implements
> EventBus {
> >> >>> _children.put(key, childNode);
> >> >>> }
> >> >>>
> >> >>> - public void notifySubscribers(String subject, Object
> >> >>>sender, String args) {
> >> >>> + public void notifySubscribers(String subject,
> >> >>> + Object
> >> >>>sender, Serializable args) {
> >> >>> for(Subscriber subscriber : _subscribers) {
> >> >>>
> >> >>>subscriber.onPublishEvent(subject,
> >> >>>sender, args);
> >> >>> }
> >> >>>
> >> >>>
> >>
> >>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8e
> >>>>>f9e
> >>>>>32
> >> >>>c
> >> >>>/utils/src/com/cloud/utils/events/Subscriber.java
> >> >>>
> >>----------------------------------------------------------------------
> >> >>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
> >> >>>b/utils/src/com/cloud/utils/events/Subscriber.java
> >> >>> index 7af283b..c3baa6f 100644
> >> >>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
> >> >>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
> >> >>> @@ -17,6 +17,8 @@
> >> >>>
> >> >>> package com.cloud.utils.events;
> >> >>>
> >> >>> +import java.io.Serializable;
> >> >>> +
> >> >>> public interface Subscriber {
> >> >>> - void onPublishEvent(String subject, Object sender, String
> >> >>>args);
> >> >>> + void onPublishEvent(String subject, Object sender,
> >>Serializable
> >> >>>args);
> >> >>> }
> >> >>>
> >> >
> >>
> >>
Re: [DISCUSS] git commit: Architecture refactoring - Stateless
management server - Spring Framework initiatives
Posted by Kelven Yang <ke...@citrix.com>.
On 11/12/12 10:58 AM, "Chip Childers" <ch...@sungard.com> wrote:
>On Thu, Nov 8, 2012 at 7:19 PM, Kelven Yang <ke...@citrix.com>
>wrote:
>>
>> As part of architecture refactoring work, we are exploring some
>> initiatives that would help CloudStack move toward more component-based
>> architecture, one of such efforts is to standardize the way on how a
>> single individual java component to be integrated into CloudStack
>>system.
>>
>> CloudStack currently uses ComponentLocator to bootstrap components, it
>>has
>> done a great job while in the mean time, there are a couple of issues
>>with
>> this customized component injection framework (in my view).
>>
>> 1) ComponentLocator can not fully perform dependency injection, it can
>> inject independent components without a problem, however, when things
>>come
>> with dependency, it will become tricky, although most of time
>>auto-wiring
>> with @Inject annotation works, but in some other time, developers will
>> have to use following explicit wiring logic to make things work.
>>
>> @Local(value={UsageManager.class})
>> public class UsageManagerImpl implements UsageManager, Runnable {
>> public static final Logger s_logger =
>> Logger.getLogger(UsageManagerImpl.class.getName());
>>
>> protected static final String DAILY = "DAILY";
>> protected static final String WEEKLY = "WEEKLY";
>> protected static final String MONTHLY = "MONTHLY";
>>
>> private static final int HOURLY_TIME = 60;
>> private static final int DAILY_TIME = 60 * 24;
>> private static final int THREE_DAYS_IN_MINUTES = 60 * 24 * 3;
>> private static final int USAGE_AGGREGATION_RANGE_MIN = 10;
>>
>> --> hard-wiring logic goes here...
>> private final ComponentLocator _locator =
>> ComponentLocator.getLocator(UsageServer.Name, "usage-components.xml",
>> "log4j-cloud_usage");
>> private final AccountDao m_accountDao =
>> _locator.getDao(AccountDao.class);
>> private final UserStatisticsDao m_userStatsDao =
>> _locator.getDao(UserStatisticsDao.class);
>> private final UsageDao m_usageDao = _locator.getDao(UsageDao.class);
>> private final UsageVMInstanceDao m_usageInstanceDao =
>> _locator.getDao(UsageVMInstanceDao.class);
>> private final UsageIPAddressDao m_usageIPAddressDao =
>> _locator.getDao(UsageIPAddressDao.class);
>> private final UsageNetworkDao m_usageNetworkDao =
>> _locator.getDao(UsageNetworkDao.class);
>> private final UsageVolumeDao m_usageVolumeDao =
>> _locator.getDao(UsageVolumeDao.class);
>> private final UsageStorageDao m_usageStorageDao =
>> _locator.getDao(UsageStorageDao.class);
>> private final UsageLoadBalancerPolicyDao
>>m_usageLoadBalancerPolicyDao
>> = _locator.getDao(UsageLoadBalancerPolicyDao.class);
>> private final UsagePortForwardingRuleDao
>>m_usagePortForwardingRuleDao
>> = _locator.getDao(UsagePortForwardingRuleDao.class);
>> private final UsageNetworkOfferingDao m_usageNetworkOfferingDao =
>> _locator.getDao(UsageNetworkOfferingDao.class);
>> private final UsageVPNUserDao m_usageVPNUserDao =
>> _locator.getDao(UsageVPNUserDao.class);
>> private final UsageSecurityGroupDao m_usageSecurityGroupDao =
>> _locator.getDao(UsageSecurityGroupDao.class);
>> private final UsageJobDao m_usageJobDao =
>> _locator.getDao(UsageJobDao.class);
>>
>> The problem of doing so is that we create a cross-reference between
>> component and the component container, it breaks the principle of being
>> component-ized. In the above case, the component shouldn't really make
>>any
>> assumption of its container, and the other problem is that developers
>>will
>> sometimes be confused at when, under what situation, they can use
>>@Inject
>> to wire a component or they have to use run-time wiring logic like above
>> to make it work.
>>
>>
>> 2) AOP pattern is implicitly buried with current injection framework.
>>
>> AOP(Aspect Oriented Pattern) is very powerful concept, and CloudStack
>>uses
>> it a lot, @DB annotation is a very typical example. However, wiring an
>> aspect is not that explicit, it buries inside those interceptors that
>>work
>> together with ComponentLocator during injection phase. Although AOP
>> concept is powerful, but it better to be explicit, we need to encourage
>>to
>> component-ize the AOP aspect itself as component, although
>> ComponentLocator has no problem to offer AOP support, it lacks of
>>letting
>> people do it in a more explicit way.
>>
>> 3) Unit test integration
>> In the example in 1), to perform a unit test on the component, it
>>involves
>> with having to construct a mocked ComponentLocator, these little pieces
>> add up to make unit-testing a little challenge in CloudStack.
>>
>
>+1 - this is problematic
>
>>
>> 4) CloudStack specific logic
>>
>> ComponentLocator also has CloudStack specific assumptions on Adapters,
>> Managers, PluggableService etc, this has to move up to the business
>>layer
>> and leave this underlying layer generic and clean, if in the future
>>people
>> want to add some other cool stuff like CoolServiceGates etc, it requires
>> the developer to modify ComponentLocator, this kind of possibility alone
>> makes ComponentLocator itself not really a component, we should not
>> encourage that.
>>
>> As a solution, we are exploring the possibility to adopt Spring
>>Framework
>> into CloudStack, it has the ability to address all above issues, the
>>goal
>> here is to leave all these generic concerns away from CloudStack core
>> business logic, and standardize the way we program in CloudStack. The
>>goal
>> is
>>
>> 1) Individual component should be clean, no hard-coded assumption of any
>> component container framework
>> 2) System to in layered with clean boundary. No business logic leaked
>>into
>> generic plumbing layer.
>> 3) AOP pattern to be explicit, represented through aspect component and
>> explicit wiring of the AOP
>> 4) Make unit test simple, simple and simple (Junit Spring integration
>>has
>> already done that)
>>
>
>Great Goals...
>
>While Spring is an option, do you have any thoughts on Hugo's OSGi
>suggestion?
Our immediate focus right now is to first make interval component
development easier, allow loosely coupled component to be integrated into
CloudStack in a consistent and standard way. OSGi suggestion is a good
one, I think once we have internally sliced CloudStack into a dozen of
well encapsulated components, it will be a good option.
>
>Also, the AOP example you used relates to the persistence objects. On
>a related note, do you consider it a reasonable goal to switch to a
>non-custom JPA framework? IIRC, Hibernate isn't license compatible
>(LGPL?). How about Apache's own OpenJPA ( http://openjpa.apache.org/
>)?
It is not that we are not considering of it, but just the amount of work
and the priorities. Dependency Injection and Persistent framework by their
own are separated projects and there are not many reasons for CloudStack
not to use mature and popular ones so that we can focus on what we ought
to. I personally prefer to see CloudStack going towards that direction,
embrace some of the best from other communities and produce the best
Orchestration Framework from our side.
It will be easier to draw Java developers to CloudStack if the system
looks familiar other than that he/she has to learn every single major
plumbing work in order to get started. From this perspective, I support to
go with other popular persist framework like openJPA, just not sure
whether or not it is a good time. But in anyway, once Spring work is in
place, switching to these alternatives will become much easier too.
>
>>
>> Since 4.0 is already out of the door, I re-raise the discussion here
>> again, please feel free to share your opinions
>>
>> Kelven
>>
>>
>> On 10/19/12 6:14 PM, "Kelven Yang" <ke...@citrix.com> wrote:
>>
>> >David,
>> >
>> >Thanks for the remind. As we are working on a feature branch(Javelin)
>>and
>> >thought not to heat-up the mailing list while everyone is still busy on
>> >getting the 4.0 release out of the door.
>> >
>> >We are evaluating the possibility to leverage Spring Framework to
>> >standardize Dependency injection/AOP pattern usages in CloudStack.
>>Spring
>> >framework is very popular to Java community and under Apache license.
>>By
>> >switching the underlying architecture plumbing to a de-facto
>>standardized
>> >framework would help attract developers to focus more on CloudStack
>>core
>> >business logic with already familiar coding practices.
>> >
>> >We will not extensively use full featured Spring Framework, may
>>primarily
>> >on core DI/AOP features since these are commonly used in CloudStack, we
>> >also haven't decided to go with Spring annotation based approach or XML
>> >based approach yet. With currently check-ins, they are annotation based
>> >which I personally prefer, however, this may change, depends on how to
>>get
>> >our old code loaded nicely under Spring.
>> >
>> >If anyone does have a strong opinion on this, please feel free to share
>> >with us.
>> >
>> >
>> >Kelven
>> >
>> >On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
>> >
>> >>This adds a number of new dependencies.
>> >>
>> >>This needs to explicitly be discussed before it gets committed.
>> >>See below for reference:
>> >>http://markmail.org/message/huevw4ur73a64b5c
>> >>
>> >>On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
>> >>> Updated Branches:
>> >>> refs/heads/javelin a75916d45 -> 8ef9e32cf
>> >>>
>> >>>
>> >>> Architecture refactoring - Stateless management server - Spring
>> >>>Framework initiatives
>> >>>
>> >>>
>> >>> Project:
>> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
>> >>> Commit:
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef
>>>>>9e
>> >>>3
>> >>>2c
>> >>> Tree:
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e
>>>>>32
>> >>>c
>> >>> Diff:
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e
>>>>>32
>> >>>c
>> >>>
>> >>> Branch: refs/heads/javelin
>> >>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
>> >>> Parents: a75916d
>> >>> Author: Kelven Yang <ke...@citrix.com>
>> >>> Authored: Fri Oct 19 15:24:01 2012 -0700
>> >>> Committer: Kelven Yang <ke...@citrix.com>
>> >>> Committed: Fri Oct 19 15:24:15 2012 -0700
>> >>>
>> >>>
>>----------------------------------------------------------------------
>> >>> client/WEB-INF/web.xml | 9 ++-
>> >>> pom.xml | 81
>> >>>+++++++++++++++
>> >>> utils/conf/db.properties | 1 +
>> >>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
>> >>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
>> >>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
>> >>> 6 files changed, 99 insertions(+), 5 deletions(-)
>> >>>
>>----------------------------------------------------------------------
>> >>>
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/client/WEB-INF/web.xml
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
>> >>> index 50f2455..c6fd30f 100644
>> >>> --- a/client/WEB-INF/web.xml
>> >>> +++ b/client/WEB-INF/web.xml
>> >>> @@ -20,7 +20,14 @@
>> >>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
>> >>>http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
>> >>> version="2.5">
>> >>>
>> >>> -
>> >>> + <listener>
>> >>> +
>>
>>>>><listener-class>org.springframework.web.context.ContextLoaderListener<
>>>>>/l
>> >>>i
>> >>>stener-class>
>> >>> + </listener>
>> >>> + <context-param>
>> >>> + <param-name>contextConfigLocation</param-name>
>> >>> + <param-value>classpath:applicationContext.xml</param-value>
>> >>> + </context-param>
>> >>> +
>> >>> <servlet>
>> >>> <servlet-name>cloudStartupServlet</servlet-name>
>> >>>
>> >>><servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/pom.xml
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/pom.xml b/pom.xml
>> >>> index 3c14d4e..5f63ce6 100644
>> >>> --- a/pom.xml
>> >>> +++ b/pom.xml
>> >>> @@ -79,6 +79,7 @@
>> >>> <cs.servlet.version>2.4</cs.servlet.version>
>> >>> <cs.jstl.version>1.2</cs.jstl.version>
>> >>>
>>
>>>>><cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.ve
>>>>>rs
>> >>>i
>> >>>on>
>> >>> +
>>
>>>>><org.springframework.version>3.0.5.RELEASE</org.springframework.versio
>>>>>n>
>> >>> <skipTests>true</skipTests>
>> >>>
>> >>> </properties>
>> >>> @@ -169,6 +170,86 @@
>> >>> <version>${cs.junit.version}</version>
>> >>> <scope>test</scope>
>> >>> </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-core</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-expression</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-beans</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-aop</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-context</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-context-support</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-tx</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-jdbc</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-orm</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-oxm</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-web</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-webmvc</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + </dependency>
>> >>> +
>> >>> + <dependency>
>> >>> + <groupId>org.springframework</groupId>
>> >>> + <artifactId>spring-test</artifactId>
>> >>> + <version>${org.springframework.version}</version>
>> >>> + <scope>test</scope>
>> >>> + </dependency>
>> >>> +
>> >>> </dependencies>
>> >>>
>> >>> <build>
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/utils/conf/db.properties
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
>> >>> index 6bdb6d6..8d98119 100644
>> >>> --- a/utils/conf/db.properties
>> >>> +++ b/utils/conf/db.properties
>> >>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
>> >>> # CloudStack database settings
>> >>> db.cloud.username=cloud
>> >>> db.cloud.password=cloud
>> >>> +db.root.password=
>> >>> db.cloud.host=localhost
>> >>> db.cloud.port=3306
>> >>> db.cloud.name=cloud
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/utils/src/com/cloud/utils/events/EventBus.java
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
>> >>>b/utils/src/com/cloud/utils/events/EventBus.java
>> >>> index 4195acd..c1b6f70 100644
>> >>> --- a/utils/src/com/cloud/utils/events/EventBus.java
>> >>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
>> >>> @@ -17,9 +17,11 @@
>> >>>
>> >>> package com.cloud.utils.events;
>> >>>
>> >>> +import java.io.Serializable;
>> >>> +
>> >>> public interface EventBus {
>> >>> void subscribe(String subject, Subscriber subscriber);
>> >>> void unsubscribe(String subject, Subscriber subscriber);
>> >>>
>> >>> - void publish(String subject, PublishScope scope, Object
>>sender,
>> >>>String args);
>> >>> + void publish(String subject, PublishScope scope, Object
>>sender,
>> >>>Serializable args);
>> >>> }
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/utils/src/com/cloud/utils/events/EventBusBase.java
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
>> >>>b/utils/src/com/cloud/utils/events/EventBusBase.java
>> >>> index 0c135db..cd10f1d 100644
>> >>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
>> >>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
>> >>> @@ -17,6 +17,7 @@
>> >>>
>> >>> package com.cloud.utils.events;
>> >>>
>> >>> +import java.io.Serializable;
>> >>> import java.util.ArrayList;
>> >>> import java.util.HashMap;
>> >>> import java.util.List;
>> >>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
>> >>>
>> >>> @Override
>> >>> public void publish(String subject, PublishScope scope,
>>Object
>> >>>sender,
>> >>> - String args) {
>> >>> + Serializable args) {
>> >>>
>> >>> if(_gate.enter(true)) {
>> >>>
>> >>> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
>> >>> _children.put(key, childNode);
>> >>> }
>> >>>
>> >>> - public void notifySubscribers(String subject, Object
>> >>>sender, String args) {
>> >>> + public void notifySubscribers(String subject, Object
>> >>>sender, Serializable args) {
>> >>> for(Subscriber subscriber : _subscribers) {
>> >>> subscriber.onPublishEvent(subject,
>> >>>sender, args);
>> >>> }
>> >>>
>> >>>
>>
>>>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e
>>>>>32
>> >>>c
>> >>>/utils/src/com/cloud/utils/events/Subscriber.java
>> >>>
>>----------------------------------------------------------------------
>> >>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
>> >>>b/utils/src/com/cloud/utils/events/Subscriber.java
>> >>> index 7af283b..c3baa6f 100644
>> >>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
>> >>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
>> >>> @@ -17,6 +17,8 @@
>> >>>
>> >>> package com.cloud.utils.events;
>> >>>
>> >>> +import java.io.Serializable;
>> >>> +
>> >>> public interface Subscriber {
>> >>> - void onPublishEvent(String subject, Object sender, String
>> >>>args);
>> >>> + void onPublishEvent(String subject, Object sender,
>>Serializable
>> >>>args);
>> >>> }
>> >>>
>> >
>>
>>
Re: [DISCUSS] git commit: Architecture refactoring - Stateless
management server - Spring Framework initiatives
Posted by Chip Childers <ch...@sungard.com>.
On Thu, Nov 8, 2012 at 7:19 PM, Kelven Yang <ke...@citrix.com> wrote:
>
> As part of architecture refactoring work, we are exploring some
> initiatives that would help CloudStack move toward more component-based
> architecture, one of such efforts is to standardize the way on how a
> single individual java component to be integrated into CloudStack system.
>
> CloudStack currently uses ComponentLocator to bootstrap components, it has
> done a great job while in the mean time, there are a couple of issues with
> this customized component injection framework (in my view).
>
> 1) ComponentLocator can not fully perform dependency injection, it can
> inject independent components without a problem, however, when things come
> with dependency, it will become tricky, although most of time auto-wiring
> with @Inject annotation works, but in some other time, developers will
> have to use following explicit wiring logic to make things work.
>
> @Local(value={UsageManager.class})
> public class UsageManagerImpl implements UsageManager, Runnable {
> public static final Logger s_logger =
> Logger.getLogger(UsageManagerImpl.class.getName());
>
> protected static final String DAILY = "DAILY";
> protected static final String WEEKLY = "WEEKLY";
> protected static final String MONTHLY = "MONTHLY";
>
> private static final int HOURLY_TIME = 60;
> private static final int DAILY_TIME = 60 * 24;
> private static final int THREE_DAYS_IN_MINUTES = 60 * 24 * 3;
> private static final int USAGE_AGGREGATION_RANGE_MIN = 10;
>
> --> hard-wiring logic goes here...
> private final ComponentLocator _locator =
> ComponentLocator.getLocator(UsageServer.Name, "usage-components.xml",
> "log4j-cloud_usage");
> private final AccountDao m_accountDao =
> _locator.getDao(AccountDao.class);
> private final UserStatisticsDao m_userStatsDao =
> _locator.getDao(UserStatisticsDao.class);
> private final UsageDao m_usageDao = _locator.getDao(UsageDao.class);
> private final UsageVMInstanceDao m_usageInstanceDao =
> _locator.getDao(UsageVMInstanceDao.class);
> private final UsageIPAddressDao m_usageIPAddressDao =
> _locator.getDao(UsageIPAddressDao.class);
> private final UsageNetworkDao m_usageNetworkDao =
> _locator.getDao(UsageNetworkDao.class);
> private final UsageVolumeDao m_usageVolumeDao =
> _locator.getDao(UsageVolumeDao.class);
> private final UsageStorageDao m_usageStorageDao =
> _locator.getDao(UsageStorageDao.class);
> private final UsageLoadBalancerPolicyDao m_usageLoadBalancerPolicyDao
> = _locator.getDao(UsageLoadBalancerPolicyDao.class);
> private final UsagePortForwardingRuleDao m_usagePortForwardingRuleDao
> = _locator.getDao(UsagePortForwardingRuleDao.class);
> private final UsageNetworkOfferingDao m_usageNetworkOfferingDao =
> _locator.getDao(UsageNetworkOfferingDao.class);
> private final UsageVPNUserDao m_usageVPNUserDao =
> _locator.getDao(UsageVPNUserDao.class);
> private final UsageSecurityGroupDao m_usageSecurityGroupDao =
> _locator.getDao(UsageSecurityGroupDao.class);
> private final UsageJobDao m_usageJobDao =
> _locator.getDao(UsageJobDao.class);
>
> The problem of doing so is that we create a cross-reference between
> component and the component container, it breaks the principle of being
> component-ized. In the above case, the component shouldn't really make any
> assumption of its container, and the other problem is that developers will
> sometimes be confused at when, under what situation, they can use @Inject
> to wire a component or they have to use run-time wiring logic like above
> to make it work.
>
>
> 2) AOP pattern is implicitly buried with current injection framework.
>
> AOP(Aspect Oriented Pattern) is very powerful concept, and CloudStack uses
> it a lot, @DB annotation is a very typical example. However, wiring an
> aspect is not that explicit, it buries inside those interceptors that work
> together with ComponentLocator during injection phase. Although AOP
> concept is powerful, but it better to be explicit, we need to encourage to
> component-ize the AOP aspect itself as component, although
> ComponentLocator has no problem to offer AOP support, it lacks of letting
> people do it in a more explicit way.
>
> 3) Unit test integration
> In the example in 1), to perform a unit test on the component, it involves
> with having to construct a mocked ComponentLocator, these little pieces
> add up to make unit-testing a little challenge in CloudStack.
>
+1 - this is problematic
>
> 4) CloudStack specific logic
>
> ComponentLocator also has CloudStack specific assumptions on Adapters,
> Managers, PluggableService etc, this has to move up to the business layer
> and leave this underlying layer generic and clean, if in the future people
> want to add some other cool stuff like CoolServiceGates etc, it requires
> the developer to modify ComponentLocator, this kind of possibility alone
> makes ComponentLocator itself not really a component, we should not
> encourage that.
>
> As a solution, we are exploring the possibility to adopt Spring Framework
> into CloudStack, it has the ability to address all above issues, the goal
> here is to leave all these generic concerns away from CloudStack core
> business logic, and standardize the way we program in CloudStack. The goal
> is
>
> 1) Individual component should be clean, no hard-coded assumption of any
> component container framework
> 2) System to in layered with clean boundary. No business logic leaked into
> generic plumbing layer.
> 3) AOP pattern to be explicit, represented through aspect component and
> explicit wiring of the AOP
> 4) Make unit test simple, simple and simple (Junit Spring integration has
> already done that)
>
Great Goals...
While Spring is an option, do you have any thoughts on Hugo's OSGi suggestion?
Also, the AOP example you used relates to the persistence objects. On
a related note, do you consider it a reasonable goal to switch to a
non-custom JPA framework? IIRC, Hibernate isn't license compatible
(LGPL?). How about Apache's own OpenJPA ( http://openjpa.apache.org/
)?
>
> Since 4.0 is already out of the door, I re-raise the discussion here
> again, please feel free to share your opinions
>
> Kelven
>
>
> On 10/19/12 6:14 PM, "Kelven Yang" <ke...@citrix.com> wrote:
>
> >David,
> >
> >Thanks for the remind. As we are working on a feature branch(Javelin) and
> >thought not to heat-up the mailing list while everyone is still busy on
> >getting the 4.0 release out of the door.
> >
> >We are evaluating the possibility to leverage Spring Framework to
> >standardize Dependency injection/AOP pattern usages in CloudStack. Spring
> >framework is very popular to Java community and under Apache license. By
> >switching the underlying architecture plumbing to a de-facto standardized
> >framework would help attract developers to focus more on CloudStack core
> >business logic with already familiar coding practices.
> >
> >We will not extensively use full featured Spring Framework, may primarily
> >on core DI/AOP features since these are commonly used in CloudStack, we
> >also haven't decided to go with Spring annotation based approach or XML
> >based approach yet. With currently check-ins, they are annotation based
> >which I personally prefer, however, this may change, depends on how to get
> >our old code loaded nicely under Spring.
> >
> >If anyone does have a strong opinion on this, please feel free to share
> >with us.
> >
> >
> >Kelven
> >
> >On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
> >
> >>This adds a number of new dependencies.
> >>
> >>This needs to explicitly be discussed before it gets committed.
> >>See below for reference:
> >>http://markmail.org/message/huevw4ur73a64b5c
> >>
> >>On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
> >>> Updated Branches:
> >>> refs/heads/javelin a75916d45 -> 8ef9e32cf
> >>>
> >>>
> >>> Architecture refactoring - Stateless management server - Spring
> >>>Framework initiatives
> >>>
> >>>
> >>> Project:
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
> >>> Commit:
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef9e
> >>>3
> >>>2c
> >>> Tree:
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e32
> >>>c
> >>> Diff:
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e32
> >>>c
> >>>
> >>> Branch: refs/heads/javelin
> >>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
> >>> Parents: a75916d
> >>> Author: Kelven Yang <ke...@citrix.com>
> >>> Authored: Fri Oct 19 15:24:01 2012 -0700
> >>> Committer: Kelven Yang <ke...@citrix.com>
> >>> Committed: Fri Oct 19 15:24:15 2012 -0700
> >>>
> >>> ----------------------------------------------------------------------
> >>> client/WEB-INF/web.xml | 9 ++-
> >>> pom.xml | 81
> >>>+++++++++++++++
> >>> utils/conf/db.properties | 1 +
> >>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
> >>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
> >>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
> >>> 6 files changed, 99 insertions(+), 5 deletions(-)
> >>> ----------------------------------------------------------------------
> >>>
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/client/WEB-INF/web.xml
> >>> ----------------------------------------------------------------------
> >>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
> >>> index 50f2455..c6fd30f 100644
> >>> --- a/client/WEB-INF/web.xml
> >>> +++ b/client/WEB-INF/web.xml
> >>> @@ -20,7 +20,14 @@
> >>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
> >>>http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
> >>> version="2.5">
> >>>
> >>> -
> >>> + <listener>
> >>> +
> >>><listener-class>org.springframework.web.context.ContextLoaderListener</l
> >>>i
> >>>stener-class>
> >>> + </listener>
> >>> + <context-param>
> >>> + <param-name>contextConfigLocation</param-name>
> >>> + <param-value>classpath:applicationContext.xml</param-value>
> >>> + </context-param>
> >>> +
> >>> <servlet>
> >>> <servlet-name>cloudStartupServlet</servlet-name>
> >>>
> >>><servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/pom.xml
> >>> ----------------------------------------------------------------------
> >>> diff --git a/pom.xml b/pom.xml
> >>> index 3c14d4e..5f63ce6 100644
> >>> --- a/pom.xml
> >>> +++ b/pom.xml
> >>> @@ -79,6 +79,7 @@
> >>> <cs.servlet.version>2.4</cs.servlet.version>
> >>> <cs.jstl.version>1.2</cs.jstl.version>
> >>>
> >>><cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.vers
> >>>i
> >>>on>
> >>> +
> >>><org.springframework.version>3.0.5.RELEASE</org.springframework.version>
> >>> <skipTests>true</skipTests>
> >>>
> >>> </properties>
> >>> @@ -169,6 +170,86 @@
> >>> <version>${cs.junit.version}</version>
> >>> <scope>test</scope>
> >>> </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-core</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-expression</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-beans</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-aop</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-context</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-context-support</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-tx</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-jdbc</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-orm</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-oxm</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-web</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-webmvc</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + </dependency>
> >>> +
> >>> + <dependency>
> >>> + <groupId>org.springframework</groupId>
> >>> + <artifactId>spring-test</artifactId>
> >>> + <version>${org.springframework.version}</version>
> >>> + <scope>test</scope>
> >>> + </dependency>
> >>> +
> >>> </dependencies>
> >>>
> >>> <build>
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/utils/conf/db.properties
> >>> ----------------------------------------------------------------------
> >>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
> >>> index 6bdb6d6..8d98119 100644
> >>> --- a/utils/conf/db.properties
> >>> +++ b/utils/conf/db.properties
> >>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
> >>> # CloudStack database settings
> >>> db.cloud.username=cloud
> >>> db.cloud.password=cloud
> >>> +db.root.password=
> >>> db.cloud.host=localhost
> >>> db.cloud.port=3306
> >>> db.cloud.name=cloud
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/utils/src/com/cloud/utils/events/EventBus.java
> >>> ----------------------------------------------------------------------
> >>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
> >>>b/utils/src/com/cloud/utils/events/EventBus.java
> >>> index 4195acd..c1b6f70 100644
> >>> --- a/utils/src/com/cloud/utils/events/EventBus.java
> >>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
> >>> @@ -17,9 +17,11 @@
> >>>
> >>> package com.cloud.utils.events;
> >>>
> >>> +import java.io.Serializable;
> >>> +
> >>> public interface EventBus {
> >>> void subscribe(String subject, Subscriber subscriber);
> >>> void unsubscribe(String subject, Subscriber subscriber);
> >>>
> >>> - void publish(String subject, PublishScope scope, Object sender,
> >>>String args);
> >>> + void publish(String subject, PublishScope scope, Object sender,
> >>>Serializable args);
> >>> }
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/utils/src/com/cloud/utils/events/EventBusBase.java
> >>> ----------------------------------------------------------------------
> >>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
> >>>b/utils/src/com/cloud/utils/events/EventBusBase.java
> >>> index 0c135db..cd10f1d 100644
> >>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
> >>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
> >>> @@ -17,6 +17,7 @@
> >>>
> >>> package com.cloud.utils.events;
> >>>
> >>> +import java.io.Serializable;
> >>> import java.util.ArrayList;
> >>> import java.util.HashMap;
> >>> import java.util.List;
> >>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
> >>>
> >>> @Override
> >>> public void publish(String subject, PublishScope scope, Object
> >>>sender,
> >>> - String args) {
> >>> + Serializable args) {
> >>>
> >>> if(_gate.enter(true)) {
> >>>
> >>> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
> >>> _children.put(key, childNode);
> >>> }
> >>>
> >>> - public void notifySubscribers(String subject, Object
> >>>sender, String args) {
> >>> + public void notifySubscribers(String subject, Object
> >>>sender, Serializable args) {
> >>> for(Subscriber subscriber : _subscribers) {
> >>> subscriber.onPublishEvent(subject,
> >>>sender, args);
> >>> }
> >>>
> >>>
> >>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
> >>>c
> >>>/utils/src/com/cloud/utils/events/Subscriber.java
> >>> ----------------------------------------------------------------------
> >>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
> >>>b/utils/src/com/cloud/utils/events/Subscriber.java
> >>> index 7af283b..c3baa6f 100644
> >>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
> >>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
> >>> @@ -17,6 +17,8 @@
> >>>
> >>> package com.cloud.utils.events;
> >>>
> >>> +import java.io.Serializable;
> >>> +
> >>> public interface Subscriber {
> >>> - void onPublishEvent(String subject, Object sender, String
> >>>args);
> >>> + void onPublishEvent(String subject, Object sender, Serializable
> >>>args);
> >>> }
> >>>
> >
>
>
Re: [DISCUSS] git commit: Architecture refactoring - Stateless management server - Spring Framework initiatives
Posted by John Burwell <jb...@basho.com>.
Kelven,
(I apologize in advance for the length of my reply.)
I agree completely that we need to consider adopting a third-party dependency injection framework. I propose that we give strong consideration to Spring because of the following additional capabilities it provides:
Authentication and Authorization: Spring Security provides robust integration with SSO facilities (CAS by default) to support enterprise authentication scenarios (including LDAP and AD). It also provides a powerful authorization capability to implement RBAC controls.
Configuration: Resolves configuration options from a hierarchy of sources and injects their values through Spring DI. It also provides the means to bind dependencies in code at runtime -- preventing a proliferation of annotations across the codebase.
Transaction Management and JDBC Framework: A powerful, annotation based transaction management facility with a nice set of abstractions for using JDBC in a robust manner.
Scheduling: Spring provides a nice set of abstractions around various Java scheduling mechanisms including Quartz.
Currently, CloudStack only authorizes users at the endpoint. Furthermore, the authentication sessions are not shared in a manner that would permit integration with other enterprise facilities (e.g. storage, LDAP, management tools, etc). Shifting to Spring Security would permit fine-grained authorization at the service boundary, and allow CloudStack to share authentication session information in a trusted manner via third-party SSO services. Finally, CloudStack would be able to defer LDAP/AD integration and password hashing strategies to the SSO services while allowing more advanced security features such as multi-factor authentication.
As discussed elsewhere on the list, the myriad of technologies integrated by CloudStack introduces many opportunities for conflicting dependencies (i.e. JAR hell), as well as, a requirement to isolate components. As such, CloudStack seems like a good candidate for a component framework such as OSGi. While the transition would require a lot of work (e.g. making the CloudStack artifacts and third-party dependencies compliant, enhancing the build process, etc), Spring was one of the original adopters of OSGi, and the dependency injection framework works well with it.
I find the Spring XML configuration to be a horrendous blight on a codebase followed closely by the proliferation of @Inject/@Component annotations everywhere. In addition to tightly coupling the codebase to a dependency injection framework (JSR-333 annotations do little to help matters, IMHO), they require test frameworks on top of frameworks to perform unit testing. The most valuable unit test suites are well-isolated and simple. The additional overhead of these test frameworks adds unnecessary complexity to test case authoring and debugging activities. Thankfully, Spring Configuration provides the means to implement dependency injection without XML or annotations everywhere. Borrowing the UsageManager example below, every subsystem (e.g. usage) provides a single class annotated with the @Configuration annotation such as the following:
com.cloud.usage;
@Configuration
public class UsageSubsystem {
@Component
private AccoutDao m_accountDao
// Inject other dependencies required by services exposed by this subsystem
// Inject configuration options required by services exposed by this subsystem
@Component
public UsageManager usageManager() {
return new UsageManagerImpl(m_accountDao, /* other dependencies and configuration options */
}
// Method per service implementation binding
}
Since the dependency injection framework is isolated in this Subsystem class, UsageManagerImpl is simplified to the following:
com.cloud.usage;
final class UsageManagerImpl implements UsageManager {
private final AccountDao m_accountDao;
// Other dependencies …
UsageManagerImpl(AccountDao accountDao, /* other dependencies and configuration options */) {
super();
this.m_accountDao = accountDao;
}
// UsageManager implementation
}
In this model, unit tests do not need to concern themselves with DI framework. They create mock implementations of each UsageManagerImpl dependency and create an instance using the new operator. Also, Spring provides a well-defined lifecycle for configuration classes, including startup and shutdown hook methods when the Lifecycle interface is implemented, and dependency graphs (e.g. Subsystem C depends on the A and B). Finally, the dependencies on the DI framework are isolated to a handful "subsystem" classes.
Currently, CloudStack maintains its own infrastructure for transaction management and JDBC infrastructure code. Spring provides a robust transaction management mechanism exposed via annotations and JDBC templates that would us to remove code under maintenance while adopting facilities that are well understood and widely used across the industry.
Finally, there are number of places in the CloudStack code based with scheduled tasks occur. Each capability is implemented independently (usually using a ScheduledTaskExecutor) with no coordination. Furthermore, none of these scheduled tasks a standard approach for crash recovery or retry. Adopting a centralized scheduling framework would not only establish consistency for these types of operations, but also allow CloudStack to leverage error recovery and retry provided by those facilities.
I am sure I have left out a myriad of details. I believe that we can simplify the codebase while increasing capability through a framework such as Spring. I also believe that adopting mechanisms for these needs that are widely used through our industry will make the codebase more approachable to potential contributors while leaving the project to focus on its core cloud management capabilities.
Thank you for sticking with my long stream of consciousness reply,
-John
On Nov 8, 2012, at 7:19 PM, Kelven Yang <ke...@citrix.com> wrote:
> As part of architecture refactoring work, we are exploring some
> initiatives that would help CloudStack move toward more component-based
> architecture, one of such efforts is to standardize the way on how a
> single individual java component to be integrated into CloudStack system.
>
> CloudStack currently uses ComponentLocator to bootstrap components, it has
> done a great job while in the mean time, there are a couple of issues with
> this customized component injection framework (in my view).
>
> 1) ComponentLocator can not fully perform dependency injection, it can
> inject independent components without a problem, however, when things come
> with dependency, it will become tricky, although most of time auto-wiring
> with @Inject annotation works, but in some other time, developers will
> have to use following explicit wiring logic to make things work.
>
> @Local(value={UsageManager.class})
> public class UsageManagerImpl implements UsageManager, Runnable {
> public static final Logger s_logger =
> Logger.getLogger(UsageManagerImpl.class.getName());
>
> protected static final String DAILY = "DAILY";
> protected static final String WEEKLY = "WEEKLY";
> protected static final String MONTHLY = "MONTHLY";
>
> private static final int HOURLY_TIME = 60;
> private static final int DAILY_TIME = 60 * 24;
> private static final int THREE_DAYS_IN_MINUTES = 60 * 24 * 3;
> private static final int USAGE_AGGREGATION_RANGE_MIN = 10;
>
> --> hard-wiring logic goes here...
> private final ComponentLocator _locator =
> ComponentLocator.getLocator(UsageServer.Name, "usage-components.xml",
> "log4j-cloud_usage");
> private final AccountDao m_accountDao =
> _locator.getDao(AccountDao.class);
> private final UserStatisticsDao m_userStatsDao =
> _locator.getDao(UserStatisticsDao.class);
> private final UsageDao m_usageDao = _locator.getDao(UsageDao.class);
> private final UsageVMInstanceDao m_usageInstanceDao =
> _locator.getDao(UsageVMInstanceDao.class);
> private final UsageIPAddressDao m_usageIPAddressDao =
> _locator.getDao(UsageIPAddressDao.class);
> private final UsageNetworkDao m_usageNetworkDao =
> _locator.getDao(UsageNetworkDao.class);
> private final UsageVolumeDao m_usageVolumeDao =
> _locator.getDao(UsageVolumeDao.class);
> private final UsageStorageDao m_usageStorageDao =
> _locator.getDao(UsageStorageDao.class);
> private final UsageLoadBalancerPolicyDao m_usageLoadBalancerPolicyDao
> = _locator.getDao(UsageLoadBalancerPolicyDao.class);
> private final UsagePortForwardingRuleDao m_usagePortForwardingRuleDao
> = _locator.getDao(UsagePortForwardingRuleDao.class);
> private final UsageNetworkOfferingDao m_usageNetworkOfferingDao =
> _locator.getDao(UsageNetworkOfferingDao.class);
> private final UsageVPNUserDao m_usageVPNUserDao =
> _locator.getDao(UsageVPNUserDao.class);
> private final UsageSecurityGroupDao m_usageSecurityGroupDao =
> _locator.getDao(UsageSecurityGroupDao.class);
> private final UsageJobDao m_usageJobDao =
> _locator.getDao(UsageJobDao.class);
>
> The problem of doing so is that we create a cross-reference between
> component and the component container, it breaks the principle of being
> component-ized. In the above case, the component shouldn't really make any
> assumption of its container, and the other problem is that developers will
> sometimes be confused at when, under what situation, they can use @Inject
> to wire a component or they have to use run-time wiring logic like above
> to make it work.
>
>
> 2) AOP pattern is implicitly buried with current injection framework.
>
> AOP(Aspect Oriented Pattern) is very powerful concept, and CloudStack uses
> it a lot, @DB annotation is a very typical example. However, wiring an
> aspect is not that explicit, it buries inside those interceptors that work
> together with ComponentLocator during injection phase. Although AOP
> concept is powerful, but it better to be explicit, we need to encourage to
> component-ize the AOP aspect itself as component, although
> ComponentLocator has no problem to offer AOP support, it lacks of letting
> people do it in a more explicit way.
>
> 3) Unit test integration
> In the example in 1), to perform a unit test on the component, it involves
> with having to construct a mocked ComponentLocator, these little pieces
> add up to make unit-testing a little challenge in CloudStack.
>
> 4) CloudStack specific logic
>
> ComponentLocator also has CloudStack specific assumptions on Adapters,
> Managers, PluggableService etc, this has to move up to the business layer
> and leave this underlying layer generic and clean, if in the future people
> want to add some other cool stuff like CoolServiceGates etc, it requires
> the developer to modify ComponentLocator, this kind of possibility alone
> makes ComponentLocator itself not really a component, we should not
> encourage that.
>
> As a solution, we are exploring the possibility to adopt Spring Framework
> into CloudStack, it has the ability to address all above issues, the goal
> here is to leave all these generic concerns away from CloudStack core
> business logic, and standardize the way we program in CloudStack. The goal
> is
>
> 1) Individual component should be clean, no hard-coded assumption of any
> component container framework
> 2) System to in layered with clean boundary. No business logic leaked into
> generic plumbing layer.
> 3) AOP pattern to be explicit, represented through aspect component and
> explicit wiring of the AOP
> 4) Make unit test simple, simple and simple (Junit Spring integration has
> already done that)
>
> Since 4.0 is already out of the door, I re-raise the discussion here
> again, please feel free to share your opinions
>
> Kelven
>
>
> On 10/19/12 6:14 PM, "Kelven Yang" <ke...@citrix.com> wrote:
>
>> David,
>>
>> Thanks for the remind. As we are working on a feature branch(Javelin) and
>> thought not to heat-up the mailing list while everyone is still busy on
>> getting the 4.0 release out of the door.
>>
>> We are evaluating the possibility to leverage Spring Framework to
>> standardize Dependency injection/AOP pattern usages in CloudStack. Spring
>> framework is very popular to Java community and under Apache license. By
>> switching the underlying architecture plumbing to a de-facto standardized
>> framework would help attract developers to focus more on CloudStack core
>> business logic with already familiar coding practices.
>>
>> We will not extensively use full featured Spring Framework, may primarily
>> on core DI/AOP features since these are commonly used in CloudStack, we
>> also haven't decided to go with Spring annotation based approach or XML
>> based approach yet. With currently check-ins, they are annotation based
>> which I personally prefer, however, this may change, depends on how to get
>> our old code loaded nicely under Spring.
>>
>> If anyone does have a strong opinion on this, please feel free to share
>> with us.
>>
>>
>> Kelven
>>
>> On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
>>
>>> This adds a number of new dependencies.
>>>
>>> This needs to explicitly be discussed before it gets committed.
>>> See below for reference:
>>> http://markmail.org/message/huevw4ur73a64b5c
>>>
>>> On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
>>>> Updated Branches:
>>>> refs/heads/javelin a75916d45 -> 8ef9e32cf
>>>>
>>>>
>>>> Architecture refactoring - Stateless management server - Spring
>>>> Framework initiatives
>>>>
>>>>
>>>> Project:
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
>>>> Commit:
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef9e
>>>> 3
>>>> 2c
>>>> Tree:
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e32
>>>> c
>>>> Diff:
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e32
>>>> c
>>>>
>>>> Branch: refs/heads/javelin
>>>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
>>>> Parents: a75916d
>>>> Author: Kelven Yang <ke...@citrix.com>
>>>> Authored: Fri Oct 19 15:24:01 2012 -0700
>>>> Committer: Kelven Yang <ke...@citrix.com>
>>>> Committed: Fri Oct 19 15:24:15 2012 -0700
>>>>
>>>> ----------------------------------------------------------------------
>>>> client/WEB-INF/web.xml | 9 ++-
>>>> pom.xml | 81
>>>> +++++++++++++++
>>>> utils/conf/db.properties | 1 +
>>>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
>>>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
>>>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
>>>> 6 files changed, 99 insertions(+), 5 deletions(-)
>>>> ----------------------------------------------------------------------
>>>>
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /client/WEB-INF/web.xml
>>>> ----------------------------------------------------------------------
>>>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
>>>> index 50f2455..c6fd30f 100644
>>>> --- a/client/WEB-INF/web.xml
>>>> +++ b/client/WEB-INF/web.xml
>>>> @@ -20,7 +20,14 @@
>>>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
>>>> http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
>>>> version="2.5">
>>>>
>>>> -
>>>> + <listener>
>>>> +
>>>> <listener-class>org.springframework.web.context.ContextLoaderListener</l
>>>> i
>>>> stener-class>
>>>> + </listener>
>>>> + <context-param>
>>>> + <param-name>contextConfigLocation</param-name>
>>>> + <param-value>classpath:applicationContext.xml</param-value>
>>>> + </context-param>
>>>> +
>>>> <servlet>
>>>> <servlet-name>cloudStartupServlet</servlet-name>
>>>>
>>>> <servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /pom.xml
>>>> ----------------------------------------------------------------------
>>>> diff --git a/pom.xml b/pom.xml
>>>> index 3c14d4e..5f63ce6 100644
>>>> --- a/pom.xml
>>>> +++ b/pom.xml
>>>> @@ -79,6 +79,7 @@
>>>> <cs.servlet.version>2.4</cs.servlet.version>
>>>> <cs.jstl.version>1.2</cs.jstl.version>
>>>>
>>>> <cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.vers
>>>> i
>>>> on>
>>>> +
>>>> <org.springframework.version>3.0.5.RELEASE</org.springframework.version>
>>>> <skipTests>true</skipTests>
>>>>
>>>> </properties>
>>>> @@ -169,6 +170,86 @@
>>>> <version>${cs.junit.version}</version>
>>>> <scope>test</scope>
>>>> </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-core</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-expression</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-beans</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-aop</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-context</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-context-support</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-tx</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-jdbc</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-orm</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-oxm</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-web</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-webmvc</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + </dependency>
>>>> +
>>>> + <dependency>
>>>> + <groupId>org.springframework</groupId>
>>>> + <artifactId>spring-test</artifactId>
>>>> + <version>${org.springframework.version}</version>
>>>> + <scope>test</scope>
>>>> + </dependency>
>>>> +
>>>> </dependencies>
>>>>
>>>> <build>
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /utils/conf/db.properties
>>>> ----------------------------------------------------------------------
>>>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
>>>> index 6bdb6d6..8d98119 100644
>>>> --- a/utils/conf/db.properties
>>>> +++ b/utils/conf/db.properties
>>>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
>>>> # CloudStack database settings
>>>> db.cloud.username=cloud
>>>> db.cloud.password=cloud
>>>> +db.root.password=
>>>> db.cloud.host=localhost
>>>> db.cloud.port=3306
>>>> db.cloud.name=cloud
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /utils/src/com/cloud/utils/events/EventBus.java
>>>> ----------------------------------------------------------------------
>>>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
>>>> b/utils/src/com/cloud/utils/events/EventBus.java
>>>> index 4195acd..c1b6f70 100644
>>>> --- a/utils/src/com/cloud/utils/events/EventBus.java
>>>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
>>>> @@ -17,9 +17,11 @@
>>>>
>>>> package com.cloud.utils.events;
>>>>
>>>> +import java.io.Serializable;
>>>> +
>>>> public interface EventBus {
>>>> void subscribe(String subject, Subscriber subscriber);
>>>> void unsubscribe(String subject, Subscriber subscriber);
>>>>
>>>> - void publish(String subject, PublishScope scope, Object sender,
>>>> String args);
>>>> + void publish(String subject, PublishScope scope, Object sender,
>>>> Serializable args);
>>>> }
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /utils/src/com/cloud/utils/events/EventBusBase.java
>>>> ----------------------------------------------------------------------
>>>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
>>>> b/utils/src/com/cloud/utils/events/EventBusBase.java
>>>> index 0c135db..cd10f1d 100644
>>>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
>>>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
>>>> @@ -17,6 +17,7 @@
>>>>
>>>> package com.cloud.utils.events;
>>>>
>>>> +import java.io.Serializable;
>>>> import java.util.ArrayList;
>>>> import java.util.HashMap;
>>>> import java.util.List;
>>>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
>>>>
>>>> @Override
>>>> public void publish(String subject, PublishScope scope, Object
>>>> sender,
>>>> - String args) {
>>>> + Serializable args) {
>>>>
>>>> if(_gate.enter(true)) {
>>>>
>>>> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
>>>> _children.put(key, childNode);
>>>> }
>>>>
>>>> - public void notifySubscribers(String subject, Object
>>>> sender, String args) {
>>>> + public void notifySubscribers(String subject, Object
>>>> sender, Serializable args) {
>>>> for(Subscriber subscriber : _subscribers) {
>>>> subscriber.onPublishEvent(subject,
>>>> sender, args);
>>>> }
>>>>
>>>>
>>>> http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>> c
>>>> /utils/src/com/cloud/utils/events/Subscriber.java
>>>> ----------------------------------------------------------------------
>>>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
>>>> b/utils/src/com/cloud/utils/events/Subscriber.java
>>>> index 7af283b..c3baa6f 100644
>>>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
>>>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
>>>> @@ -17,6 +17,8 @@
>>>>
>>>> package com.cloud.utils.events;
>>>>
>>>> +import java.io.Serializable;
>>>> +
>>>> public interface Subscriber {
>>>> - void onPublishEvent(String subject, Object sender, String
>>>> args);
>>>> + void onPublishEvent(String subject, Object sender, Serializable
>>>> args);
>>>> }
>>>>
>>
>
[DISCUSS] git commit: Architecture refactoring - Stateless
management server - Spring Framework initiatives
Posted by Kelven Yang <ke...@citrix.com>.
As part of architecture refactoring work, we are exploring some
initiatives that would help CloudStack move toward more component-based
architecture, one of such efforts is to standardize the way on how a
single individual java component to be integrated into CloudStack system.
CloudStack currently uses ComponentLocator to bootstrap components, it has
done a great job while in the mean time, there are a couple of issues with
this customized component injection framework (in my view).
1) ComponentLocator can not fully perform dependency injection, it can
inject independent components without a problem, however, when things come
with dependency, it will become tricky, although most of time auto-wiring
with @Inject annotation works, but in some other time, developers will
have to use following explicit wiring logic to make things work.
@Local(value={UsageManager.class})
public class UsageManagerImpl implements UsageManager, Runnable {
public static final Logger s_logger =
Logger.getLogger(UsageManagerImpl.class.getName());
protected static final String DAILY = "DAILY";
protected static final String WEEKLY = "WEEKLY";
protected static final String MONTHLY = "MONTHLY";
private static final int HOURLY_TIME = 60;
private static final int DAILY_TIME = 60 * 24;
private static final int THREE_DAYS_IN_MINUTES = 60 * 24 * 3;
private static final int USAGE_AGGREGATION_RANGE_MIN = 10;
--> hard-wiring logic goes here...
private final ComponentLocator _locator =
ComponentLocator.getLocator(UsageServer.Name, "usage-components.xml",
"log4j-cloud_usage");
private final AccountDao m_accountDao =
_locator.getDao(AccountDao.class);
private final UserStatisticsDao m_userStatsDao =
_locator.getDao(UserStatisticsDao.class);
private final UsageDao m_usageDao = _locator.getDao(UsageDao.class);
private final UsageVMInstanceDao m_usageInstanceDao =
_locator.getDao(UsageVMInstanceDao.class);
private final UsageIPAddressDao m_usageIPAddressDao =
_locator.getDao(UsageIPAddressDao.class);
private final UsageNetworkDao m_usageNetworkDao =
_locator.getDao(UsageNetworkDao.class);
private final UsageVolumeDao m_usageVolumeDao =
_locator.getDao(UsageVolumeDao.class);
private final UsageStorageDao m_usageStorageDao =
_locator.getDao(UsageStorageDao.class);
private final UsageLoadBalancerPolicyDao m_usageLoadBalancerPolicyDao
= _locator.getDao(UsageLoadBalancerPolicyDao.class);
private final UsagePortForwardingRuleDao m_usagePortForwardingRuleDao
= _locator.getDao(UsagePortForwardingRuleDao.class);
private final UsageNetworkOfferingDao m_usageNetworkOfferingDao =
_locator.getDao(UsageNetworkOfferingDao.class);
private final UsageVPNUserDao m_usageVPNUserDao =
_locator.getDao(UsageVPNUserDao.class);
private final UsageSecurityGroupDao m_usageSecurityGroupDao =
_locator.getDao(UsageSecurityGroupDao.class);
private final UsageJobDao m_usageJobDao =
_locator.getDao(UsageJobDao.class);
The problem of doing so is that we create a cross-reference between
component and the component container, it breaks the principle of being
component-ized. In the above case, the component shouldn't really make any
assumption of its container, and the other problem is that developers will
sometimes be confused at when, under what situation, they can use @Inject
to wire a component or they have to use run-time wiring logic like above
to make it work.
2) AOP pattern is implicitly buried with current injection framework.
AOP(Aspect Oriented Pattern) is very powerful concept, and CloudStack uses
it a lot, @DB annotation is a very typical example. However, wiring an
aspect is not that explicit, it buries inside those interceptors that work
together with ComponentLocator during injection phase. Although AOP
concept is powerful, but it better to be explicit, we need to encourage to
component-ize the AOP aspect itself as component, although
ComponentLocator has no problem to offer AOP support, it lacks of letting
people do it in a more explicit way.
3) Unit test integration
In the example in 1), to perform a unit test on the component, it involves
with having to construct a mocked ComponentLocator, these little pieces
add up to make unit-testing a little challenge in CloudStack.
4) CloudStack specific logic
ComponentLocator also has CloudStack specific assumptions on Adapters,
Managers, PluggableService etc, this has to move up to the business layer
and leave this underlying layer generic and clean, if in the future people
want to add some other cool stuff like CoolServiceGates etc, it requires
the developer to modify ComponentLocator, this kind of possibility alone
makes ComponentLocator itself not really a component, we should not
encourage that.
As a solution, we are exploring the possibility to adopt Spring Framework
into CloudStack, it has the ability to address all above issues, the goal
here is to leave all these generic concerns away from CloudStack core
business logic, and standardize the way we program in CloudStack. The goal
is
1) Individual component should be clean, no hard-coded assumption of any
component container framework
2) System to in layered with clean boundary. No business logic leaked into
generic plumbing layer.
3) AOP pattern to be explicit, represented through aspect component and
explicit wiring of the AOP
4) Make unit test simple, simple and simple (Junit Spring integration has
already done that)
Since 4.0 is already out of the door, I re-raise the discussion here
again, please feel free to share your opinions
Kelven
On 10/19/12 6:14 PM, "Kelven Yang" <ke...@citrix.com> wrote:
>David,
>
>Thanks for the remind. As we are working on a feature branch(Javelin) and
>thought not to heat-up the mailing list while everyone is still busy on
>getting the 4.0 release out of the door.
>
>We are evaluating the possibility to leverage Spring Framework to
>standardize Dependency injection/AOP pattern usages in CloudStack. Spring
>framework is very popular to Java community and under Apache license. By
>switching the underlying architecture plumbing to a de-facto standardized
>framework would help attract developers to focus more on CloudStack core
>business logic with already familiar coding practices.
>
>We will not extensively use full featured Spring Framework, may primarily
>on core DI/AOP features since these are commonly used in CloudStack, we
>also haven't decided to go with Spring annotation based approach or XML
>based approach yet. With currently check-ins, they are annotation based
>which I personally prefer, however, this may change, depends on how to get
>our old code loaded nicely under Spring.
>
>If anyone does have a strong opinion on this, please feel free to share
>with us.
>
>
>Kelven
>
>On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
>
>>This adds a number of new dependencies.
>>
>>This needs to explicitly be discussed before it gets committed.
>>See below for reference:
>>http://markmail.org/message/huevw4ur73a64b5c
>>
>>On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
>>> Updated Branches:
>>> refs/heads/javelin a75916d45 -> 8ef9e32cf
>>>
>>>
>>> Architecture refactoring - Stateless management server - Spring
>>>Framework initiatives
>>>
>>>
>>> Project:
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
>>> Commit:
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef9e
>>>3
>>>2c
>>> Tree:
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e32
>>>c
>>> Diff:
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e32
>>>c
>>>
>>> Branch: refs/heads/javelin
>>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
>>> Parents: a75916d
>>> Author: Kelven Yang <ke...@citrix.com>
>>> Authored: Fri Oct 19 15:24:01 2012 -0700
>>> Committer: Kelven Yang <ke...@citrix.com>
>>> Committed: Fri Oct 19 15:24:15 2012 -0700
>>>
>>> ----------------------------------------------------------------------
>>> client/WEB-INF/web.xml | 9 ++-
>>> pom.xml | 81
>>>+++++++++++++++
>>> utils/conf/db.properties | 1 +
>>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
>>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
>>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
>>> 6 files changed, 99 insertions(+), 5 deletions(-)
>>> ----------------------------------------------------------------------
>>>
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/client/WEB-INF/web.xml
>>> ----------------------------------------------------------------------
>>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
>>> index 50f2455..c6fd30f 100644
>>> --- a/client/WEB-INF/web.xml
>>> +++ b/client/WEB-INF/web.xml
>>> @@ -20,7 +20,14 @@
>>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
>>>http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
>>> version="2.5">
>>>
>>> -
>>> + <listener>
>>> +
>>><listener-class>org.springframework.web.context.ContextLoaderListener</l
>>>i
>>>stener-class>
>>> + </listener>
>>> + <context-param>
>>> + <param-name>contextConfigLocation</param-name>
>>> + <param-value>classpath:applicationContext.xml</param-value>
>>> + </context-param>
>>> +
>>> <servlet>
>>> <servlet-name>cloudStartupServlet</servlet-name>
>>>
>>><servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/pom.xml
>>> ----------------------------------------------------------------------
>>> diff --git a/pom.xml b/pom.xml
>>> index 3c14d4e..5f63ce6 100644
>>> --- a/pom.xml
>>> +++ b/pom.xml
>>> @@ -79,6 +79,7 @@
>>> <cs.servlet.version>2.4</cs.servlet.version>
>>> <cs.jstl.version>1.2</cs.jstl.version>
>>>
>>><cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.vers
>>>i
>>>on>
>>> +
>>><org.springframework.version>3.0.5.RELEASE</org.springframework.version>
>>> <skipTests>true</skipTests>
>>>
>>> </properties>
>>> @@ -169,6 +170,86 @@
>>> <version>${cs.junit.version}</version>
>>> <scope>test</scope>
>>> </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-core</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-expression</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-beans</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-aop</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-context</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-context-support</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-tx</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-jdbc</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-orm</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-oxm</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-web</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-webmvc</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + </dependency>
>>> +
>>> + <dependency>
>>> + <groupId>org.springframework</groupId>
>>> + <artifactId>spring-test</artifactId>
>>> + <version>${org.springframework.version}</version>
>>> + <scope>test</scope>
>>> + </dependency>
>>> +
>>> </dependencies>
>>>
>>> <build>
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/utils/conf/db.properties
>>> ----------------------------------------------------------------------
>>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
>>> index 6bdb6d6..8d98119 100644
>>> --- a/utils/conf/db.properties
>>> +++ b/utils/conf/db.properties
>>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
>>> # CloudStack database settings
>>> db.cloud.username=cloud
>>> db.cloud.password=cloud
>>> +db.root.password=
>>> db.cloud.host=localhost
>>> db.cloud.port=3306
>>> db.cloud.name=cloud
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/utils/src/com/cloud/utils/events/EventBus.java
>>> ----------------------------------------------------------------------
>>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
>>>b/utils/src/com/cloud/utils/events/EventBus.java
>>> index 4195acd..c1b6f70 100644
>>> --- a/utils/src/com/cloud/utils/events/EventBus.java
>>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
>>> @@ -17,9 +17,11 @@
>>>
>>> package com.cloud.utils.events;
>>>
>>> +import java.io.Serializable;
>>> +
>>> public interface EventBus {
>>> void subscribe(String subject, Subscriber subscriber);
>>> void unsubscribe(String subject, Subscriber subscriber);
>>>
>>> - void publish(String subject, PublishScope scope, Object sender,
>>>String args);
>>> + void publish(String subject, PublishScope scope, Object sender,
>>>Serializable args);
>>> }
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/utils/src/com/cloud/utils/events/EventBusBase.java
>>> ----------------------------------------------------------------------
>>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
>>>b/utils/src/com/cloud/utils/events/EventBusBase.java
>>> index 0c135db..cd10f1d 100644
>>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
>>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
>>> @@ -17,6 +17,7 @@
>>>
>>> package com.cloud.utils.events;
>>>
>>> +import java.io.Serializable;
>>> import java.util.ArrayList;
>>> import java.util.HashMap;
>>> import java.util.List;
>>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
>>>
>>> @Override
>>> public void publish(String subject, PublishScope scope, Object
>>>sender,
>>> - String args) {
>>> + Serializable args) {
>>>
>>> if(_gate.enter(true)) {
>>>
>>> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
>>> _children.put(key, childNode);
>>> }
>>>
>>> - public void notifySubscribers(String subject, Object
>>>sender, String args) {
>>> + public void notifySubscribers(String subject, Object
>>>sender, Serializable args) {
>>> for(Subscriber subscriber : _subscribers) {
>>> subscriber.onPublishEvent(subject,
>>>sender, args);
>>> }
>>>
>>>
>>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32
>>>c
>>>/utils/src/com/cloud/utils/events/Subscriber.java
>>> ----------------------------------------------------------------------
>>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
>>>b/utils/src/com/cloud/utils/events/Subscriber.java
>>> index 7af283b..c3baa6f 100644
>>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
>>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
>>> @@ -17,6 +17,8 @@
>>>
>>> package com.cloud.utils.events;
>>>
>>> +import java.io.Serializable;
>>> +
>>> public interface Subscriber {
>>> - void onPublishEvent(String subject, Object sender, String
>>>args);
>>> + void onPublishEvent(String subject, Object sender, Serializable
>>>args);
>>> }
>>>
>
Re: git commit: Architecture refactoring - Stateless management
server - Spring Framework initiatives
Posted by Kelven Yang <ke...@citrix.com>.
David,
Thanks for the remind. As we are working on a feature branch(Javelin) and
thought not to heat-up the mailing list while everyone is still busy on
getting the 4.0 release out of the door.
We are evaluating the possibility to leverage Spring Framework to
standardize Dependency injection/AOP pattern usages in CloudStack. Spring
framework is very popular to Java community and under Apache license. By
switching the underlying architecture plumbing to a de-facto standardized
framework would help attract developers to focus more on CloudStack core
business logic with already familiar coding practices.
We will not extensively use full featured Spring Framework, may primarily
on core DI/AOP features since these are commonly used in CloudStack, we
also haven't decided to go with Spring annotation based approach or XML
based approach yet. With currently check-ins, they are annotation based
which I personally prefer, however, this may change, depends on how to get
our old code loaded nicely under Spring.
If anyone does have a strong opinion on this, please feel free to share
with us.
Kelven
On 10/19/12 3:47 PM, "David Nalley" <da...@gnsa.us> wrote:
>This adds a number of new dependencies.
>
>This needs to explicitly be discussed before it gets committed.
>See below for reference:
>http://markmail.org/message/huevw4ur73a64b5c
>
>On Fri, Oct 19, 2012 at 6:25 PM, <ke...@apache.org> wrote:
>> Updated Branches:
>> refs/heads/javelin a75916d45 -> 8ef9e32cf
>>
>>
>> Architecture refactoring - Stateless management server - Spring
>>Framework initiatives
>>
>>
>> Project:
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
>> Commit:
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/8ef9e3
>>2c
>> Tree:
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/8ef9e32c
>> Diff:
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/8ef9e32c
>>
>> Branch: refs/heads/javelin
>> Commit: 8ef9e32cfda4b1ce138ac167caa26521bd7a3508
>> Parents: a75916d
>> Author: Kelven Yang <ke...@citrix.com>
>> Authored: Fri Oct 19 15:24:01 2012 -0700
>> Committer: Kelven Yang <ke...@citrix.com>
>> Committed: Fri Oct 19 15:24:15 2012 -0700
>>
>> ----------------------------------------------------------------------
>> client/WEB-INF/web.xml | 9 ++-
>> pom.xml | 81
>>+++++++++++++++
>> utils/conf/db.properties | 1 +
>> utils/src/com/cloud/utils/events/EventBus.java | 4 +-
>> utils/src/com/cloud/utils/events/EventBusBase.java | 5 +-
>> utils/src/com/cloud/utils/events/Subscriber.java | 4 +-
>> 6 files changed, 99 insertions(+), 5 deletions(-)
>> ----------------------------------------------------------------------
>>
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/client/WEB-INF/web.xml
>> ----------------------------------------------------------------------
>> diff --git a/client/WEB-INF/web.xml b/client/WEB-INF/web.xml
>> index 50f2455..c6fd30f 100644
>> --- a/client/WEB-INF/web.xml
>> +++ b/client/WEB-INF/web.xml
>> @@ -20,7 +20,14 @@
>> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
>>http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
>> version="2.5">
>>
>> -
>> + <listener>
>> +
>><listener-class>org.springframework.web.context.ContextLoaderListener</li
>>stener-class>
>> + </listener>
>> + <context-param>
>> + <param-name>contextConfigLocation</param-name>
>> + <param-value>classpath:applicationContext.xml</param-value>
>> + </context-param>
>> +
>> <servlet>
>> <servlet-name>cloudStartupServlet</servlet-name>
>>
>><servlet-class>com.cloud.servlet.CloudStartupServlet</servlet-class>
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/pom.xml
>> ----------------------------------------------------------------------
>> diff --git a/pom.xml b/pom.xml
>> index 3c14d4e..5f63ce6 100644
>> --- a/pom.xml
>> +++ b/pom.xml
>> @@ -79,6 +79,7 @@
>> <cs.servlet.version>2.4</cs.servlet.version>
>> <cs.jstl.version>1.2</cs.jstl.version>
>>
>><cs.selenium.server.version>1.0-20081010.060147</cs.selenium.server.versi
>>on>
>> +
>><org.springframework.version>3.0.5.RELEASE</org.springframework.version>
>> <skipTests>true</skipTests>
>>
>> </properties>
>> @@ -169,6 +170,86 @@
>> <version>${cs.junit.version}</version>
>> <scope>test</scope>
>> </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-core</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-expression</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-beans</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-aop</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-context</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-context-support</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-tx</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-jdbc</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-orm</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-oxm</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-web</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-webmvc</artifactId>
>> + <version>${org.springframework.version}</version>
>> + </dependency>
>> +
>> + <dependency>
>> + <groupId>org.springframework</groupId>
>> + <artifactId>spring-test</artifactId>
>> + <version>${org.springframework.version}</version>
>> + <scope>test</scope>
>> + </dependency>
>> +
>> </dependencies>
>>
>> <build>
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/utils/conf/db.properties
>> ----------------------------------------------------------------------
>> diff --git a/utils/conf/db.properties b/utils/conf/db.properties
>> index 6bdb6d6..8d98119 100644
>> --- a/utils/conf/db.properties
>> +++ b/utils/conf/db.properties
>> @@ -24,6 +24,7 @@ cluster.servlet.port=9090
>> # CloudStack database settings
>> db.cloud.username=cloud
>> db.cloud.password=cloud
>> +db.root.password=
>> db.cloud.host=localhost
>> db.cloud.port=3306
>> db.cloud.name=cloud
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/utils/src/com/cloud/utils/events/EventBus.java
>> ----------------------------------------------------------------------
>> diff --git a/utils/src/com/cloud/utils/events/EventBus.java
>>b/utils/src/com/cloud/utils/events/EventBus.java
>> index 4195acd..c1b6f70 100644
>> --- a/utils/src/com/cloud/utils/events/EventBus.java
>> +++ b/utils/src/com/cloud/utils/events/EventBus.java
>> @@ -17,9 +17,11 @@
>>
>> package com.cloud.utils.events;
>>
>> +import java.io.Serializable;
>> +
>> public interface EventBus {
>> void subscribe(String subject, Subscriber subscriber);
>> void unsubscribe(String subject, Subscriber subscriber);
>>
>> - void publish(String subject, PublishScope scope, Object sender,
>>String args);
>> + void publish(String subject, PublishScope scope, Object sender,
>>Serializable args);
>> }
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/utils/src/com/cloud/utils/events/EventBusBase.java
>> ----------------------------------------------------------------------
>> diff --git a/utils/src/com/cloud/utils/events/EventBusBase.java
>>b/utils/src/com/cloud/utils/events/EventBusBase.java
>> index 0c135db..cd10f1d 100644
>> --- a/utils/src/com/cloud/utils/events/EventBusBase.java
>> +++ b/utils/src/com/cloud/utils/events/EventBusBase.java
>> @@ -17,6 +17,7 @@
>>
>> package com.cloud.utils.events;
>>
>> +import java.io.Serializable;
>> import java.util.ArrayList;
>> import java.util.HashMap;
>> import java.util.List;
>> @@ -72,7 +73,7 @@ public class EventBusBase implements EventBus {
>>
>> @Override
>> public void publish(String subject, PublishScope scope, Object
>>sender,
>> - String args) {
>> + Serializable args) {
>>
>> if(_gate.enter(true)) {
>>
>> @@ -283,7 +284,7 @@ public class EventBusBase implements EventBus {
>> _children.put(key, childNode);
>> }
>>
>> - public void notifySubscribers(String subject, Object
>>sender, String args) {
>> + public void notifySubscribers(String subject, Object
>>sender, Serializable args) {
>> for(Subscriber subscriber : _subscribers) {
>> subscriber.onPublishEvent(subject,
>>sender, args);
>> }
>>
>>
>>http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/8ef9e32c
>>/utils/src/com/cloud/utils/events/Subscriber.java
>> ----------------------------------------------------------------------
>> diff --git a/utils/src/com/cloud/utils/events/Subscriber.java
>>b/utils/src/com/cloud/utils/events/Subscriber.java
>> index 7af283b..c3baa6f 100644
>> --- a/utils/src/com/cloud/utils/events/Subscriber.java
>> +++ b/utils/src/com/cloud/utils/events/Subscriber.java
>> @@ -17,6 +17,8 @@
>>
>> package com.cloud.utils.events;
>>
>> +import java.io.Serializable;
>> +
>> public interface Subscriber {
>> - void onPublishEvent(String subject, Object sender, String args);
>> + void onPublishEvent(String subject, Object sender, Serializable
>>args);
>> }
>>