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Posted to commits@helix.apache.org by jx...@apache.org on 2023/04/27 23:08:39 UTC
svn commit: r1909461 [7/38] - in /helix/site-content: ./ 0.9.9-docs/ 0.9.9-docs/css/ 0.9.9-docs/images/ 0.9.9-docs/js/ 0.9.9-docs/recipes/ 0.9.9-docs/releasenotes/ 1.0.2-docs/ 1.0.2-docs/css/ 1.0.2-docs/images/ 1.0.2-docs/js/ 1.0.2-docs/recipes/ 1.0.2-...
Modified: helix/site-content/0.9.9-docs/team-list.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/team-list.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/team-list.html (original)
+++ helix/site-content/0.9.9-docs/team-list.html Thu Apr 27 23:08:36 2023
@@ -7,7 +7,7 @@
<!--
- Generated by Apache Maven Doxia at 2023-01-05 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -130,7 +130,7 @@
<li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Project Team</li>
- <li class="publishDate version-date pull-right">Last Published: 2023-01-05</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
Modified: helix/site-content/0.9.9-docs/tutorial_admin.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/tutorial_admin.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/tutorial_admin.html (original)
+++ helix/site-content/0.9.9-docs/tutorial_admin.html Thu Apr 27 23:08:36 2023
@@ -7,7 +7,7 @@
<!--
- Generated by Apache Maven Doxia at 2022-05-12 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -125,14 +125,12 @@
</div>
<div>
<ul class="breadcrumb">
- <li><a href="http://helix.apache.org/" title="Apache Helix" class="externalLink">Apache Helix</a></li>
- <li class="divider">/</li>
<li><a href="../" title="Apache Helix">Apache Helix</a></li>
<li class="divider">/</li>
<li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Tutorial - Admin Operations</li>
- <li class="publishDate version-date pull-right">Last Published: 2022-05-12</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
@@ -785,7 +783,7 @@ curl -d @'./untitled.txt' -H 'Content-Ty
<div class="row">
<div class="span12">
<p class="pull-right"><a href="#">Back to top</a></p>
- <p class="copyright">Copyright ©2022 <a href="https://www.apache.org/">The Apache Software Foundation</a>. All Rights Reserved.</p>
+ <p class="copyright">Copyright ©2023 <a href="http://www.apache.org">Apache Software Foundation</a>. All Rights Reserved.</p>
<p><a href="https://github.com/olamy/reflow-maven-skin" title="Reflow Maven skin">Reflow Maven skin</a> maintained by <a href="https://twitter.com/olamy" target="_blank" title="Olivier Lamy">Olivier Lamy</a>.</p>
<div class="row span16"><div>Apache Helix, Apache, the Apache feather logo, and the Apache Helix project logos are trademarks of The Apache Software Foundation.
All other marks mentioned may be trademarks or registered trademarks of their respective owners.</div>
Modified: helix/site-content/0.9.9-docs/tutorial_agent.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/tutorial_agent.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/tutorial_agent.html (original)
+++ helix/site-content/0.9.9-docs/tutorial_agent.html Thu Apr 27 23:08:36 2023
@@ -1,8 +1,13 @@
<!DOCTYPE html>
+
+
+
+
+
+
<!--
- Generated by Apache Maven Doxia at 2022-04-15
- Rendered using Maven Reflow Skin 1.0.0 (http://andriusvelykis.github.com/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -13,61 +18,84 @@
<meta name="description" content="" />
<meta http-equiv="content-language" content="en" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap.min.css" rel="stylesheet" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-responsive.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap-responsive.min.css" rel="stylesheet" />
<link href="./css/docs.css" rel="stylesheet" />
<link href="./css/reflow-skin.css" rel="stylesheet" />
-
-
+
+
<link href="./css/lightbox.css" rel="stylesheet" />
-
+
<link href="./css/site.css" rel="stylesheet" />
<link href="./css/print.css" rel="stylesheet" media="print" />
-
+
<!-- Le HTML5 shim, for IE6-8 support of HTML5 elements -->
<!--[if lt IE 9]>
- <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
+ <script src="./js/html5.js"></script>
<![endif]-->
-
- </head>
- <body class="page-$config.fileId project-$config.projectId" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
+
+
+<!-- Matomo -->
+<script>
+ var _paq = window._paq = window._paq || [];
+ _paq.push(['disableCookies']);
+ _paq.push(['trackPageView']);
+ _paq.push(['enableLinkTracking']);
+
+ (function() {
+ var u="https://analytics.apache.org";
+ _paq.push(['setTrackerUrl', u+'/matomo.php']);
+ _paq.push(['setSiteId', '15']);
+ var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+ g.async=true; g.src=u+'/matomo.js'; s.parentNode.insertBefore(g,s);
+ })();
+</script>
+<!-- End Matomo Code -->
+ </head>
+
+ <body class="page-tutorial_agent project-099-docs" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
<div class="navbar navbar-fixed-top">
<div class="navbar-inner">
<div class="container">
- <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
+ <a class="btn btn-navbar" data-toggle="collapse" data-target="#top-nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
- <div class="nav-collapse">
+ <a class="brand" href="..">Apache Helix</a>
+ <div class="nav-collapse collapse" id="top-nav-collapse">
<ul class="nav pull-right">
- <li class="active"><a href="" title="Helix 0.9.9">Helix 0.9.9 </a></li>
- <li class="dropdown active">
+ <li ><a href="index.html" title="Helix 0.9.9">Helix 0.9.9</a></li>
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Get Helix <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Download">Download </a></li>
- <li class="active"><a href="" title="Building">Building </a></li>
- <li class="active"><a href="" title="Release Notes">Release Notes </a></li>
+ <li ><a href="download.html" title="Download">Download</a></li>
+ <li ><a href="Building.html" title="Building">Building</a></li>
+ <li ><a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a></li>
</ul>
</li>
- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Hands-On <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Quick Start">Quick Start </a></li>
- <li class="active"><a href="" title="Tutorial">Tutorial </a></li>
- <li class="active"><a href="" title="Javadocs">Javadocs </a></li>
+ <li ><a href="Quickstart.html" title="Quick Start">Quick Start</a></li>
+ <li ><a href="Tutorial.html" title="Tutorial">Tutorial</a></li>
+ <li ><a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a></li>
</ul>
</li>
- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Recipes <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Distributed lock manager">Distributed lock manager </a></li>
- <li class="active"><a href="" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a></li>
- <li class="active"><a href="" title="Rsync replicated file store">Rsync replicated file store </a></li>
- <li class="active"><a href="" title="Service discovery">Service discovery </a></li>
- <li class="active"><a href="" title="Distributed task DAG execution">Distributed task DAG execution </a></li>
+ <li ><a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a></li>
+ <li ><a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a></li>
+ <li ><a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a></li>
+ <li ><a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a></li>
+ <li ><a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a></li>
</ul>
</li>
</ul>
@@ -75,30 +103,34 @@
</div>
</div>
</div>
-
+
<div class="container">
-
+
<!-- Masthead
================================================== -->
- <header class="jumbotron subhead">
+
+ <header>
+ <div class="jumbotron subhead">
<div class="row" id="banner">
<div class="span12">
<div class="pull-left">
- <a href="" id="bannerLeft"><img src="" alt='"''"' /></a>
+ <a href="http://helix.apache.org/" id="bannerLeft"><img src="../images/helix-logo.jpg" alt='"''"' /></a>
+ <p class="lead">A cluster management framework for partitioned and replicated distributed resources</p>
</div>
<div class="pull-right">
- <a href="http://www.apache.org/" id="bannerRight"><img src="" alt='"''"' /></a>
+ <a href="http://www.apache.org/" id="bannerRight"><img src="../images/feather_small.gif" alt='"''"' /></a>
</div>
</div>
</div>
+ </div>
<div>
<ul class="breadcrumb">
- <li><a href="" title="Apache Helix">Apache Helix </a></li>
+ <li><a href="../" title="Apache Helix">Apache Helix</a></li>
<li class="divider">/</li>
- <li><a href="" title="Release 0.9.9">Release 0.9.9 </a></li>
+ <li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Tutorial - Helix Agent</li>
- <li class="publishDate version-date pull-right">Last Published: 2022-04-15</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
@@ -107,94 +139,257 @@
<div class="row">
<div class="span12">
<div class="body-content">
-$bodyWithHeader
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<section>
+ <div class="page-header">
+ <h2 id="Helix_Tutorial:_Helix_Agent_.28for_non-JVM_systems.29"><a href="./Tutorial.html">Helix Tutorial</a>: Helix Agent (for non-JVM systems)</h2>
+ </div>
+ <p>Not every distributed system is written on the JVM, but many systems would benefit from the cluster management features that Helix provides. To make a non-JVM system work with Helix, you can use the Helix Agent module.</p>
+ <section>
+ <h3 id="What_is_Helix_Agent.3F">What is Helix Agent?</h3>
+ <p>Helix is built on the following assumption: if your distributed resource is modeled by a finite state machine, then Helix can tell participants when they should transition between states. In the Java API, this means implementing transition callbacks. In the Helix agent API, this means providing commands than can run for each transition.</p>
+ <p>These commands could do anything behind the scenes; Helix only requires that they exit once the state transition is complete.</p>
+ </section>
+ <section>
+ <h3 id="Configuring_Transition_Commands">Configuring Transition Commands</h3>
+ <p>Here's how to tell Helix which commands to run on state transitions:</p>
+ <section>
+ <h4 id="Java">Java</h4>
+ <p>Using the Java API, first get a configuration scope (the Helix agent supports both cluster and resource scopes, picking resource first if it is available):</p>
+ <div class="source">
+ <pre><code>// Cluster scope
+HelixConfigScope scope =
+ new HelixConfigScopeBuilder(ConfigScopeProperty.CLUSTER).forCluster(clusterName).build();
+
+// Resource scope
+HelixConfigScope scope =
+ new HelixConfigScopeBuilder(ConfigScopeProperty.RESOURCE).forCluster(clusterName).forResource(resourceName).build();
+</code></pre>
+ </div>
+ <p>Then, specify the command to run for each state transition:</p>
+ <div class="source">
+ <pre><code>// Get the configuration accessor
+ConfigAccessor configAccessor = new ConfigAccessor(_gZkClient);
+
+// Specify the script for OFFLINE --> ONLINE
+CommandConfig.Builder builder = new CommandConfig.Builder();
+CommandConfig cmdConfig =
+ builder.setTransition("OFFLINE", "ONLINE").setCommand("simpleHttpClient.py OFFLINE-ONLINE")
+ .setCommandWorkingDir(workingDir)
+ .setCommandTimeout("5000L") // optional: ms to wait before failing
+ .setPidFile(pidFile) // optional: for daemon-like systems that will write the process id to a file
+ .build();
+configAccessor.set(scope, cmdConfig.toKeyValueMap());
+
+// Specify the script for ONLINE --> OFFLINE
+builder = new CommandConfig.Builder();
+cmdConfig =
+ builder.setTransition("ONLINE", "OFFLINE").setCommand("simpleHttpClient.py ONLINE-OFFLINE")
+ .setCommandWorkingDir(workingDir)
+ .build();
+configAccessor.set(scope, cmdConfig.toKeyValueMap());
+
+// Specify NOP for OFFLINE --> DROPPED
+builder = new CommandConfig.Builder();
+cmdConfig =
+ builder.setTransition("OFFLINE", "DROPPED")
+ .setCommand(CommandAttribute.NOP.getName())
+ .build();
+configAccessor.set(scope, cmdConfig.toKeyValueMap());
+</code></pre>
+ </div>
+ <p>In this example, we have a program called simpleHttpClient.py that we call for all transitions, only changing the arguments that are passed in. However, there is no requirement that each transition invoke the same program; this API allows running arbitrary commands in arbitrary directories with arbitrary arguments.</p>
+ <p>Notice that that for the OFFLINE --> DROPPED transition, we do not run any command (specifically, we specify the NOP command). This just tells Helix that the system doesn't care about when things are dropped, and it can consider the transition already done.</p>
+ </section>
+ <section>
+ <h4 id="Command_Line">Command Line</h4>
+ <p>It is also possible to configure everything directly from the command line. Here's how that would look for cluster-wide configuration:</p>
+ <div class="source">
+ <pre><code># Specify the script for OFFLINE --> ONLINE
+/helix-admin.sh --zkSvr localhost:2181 --setConfig CLUSTER clusterName OFFLINE-ONLINE.command="simpleHttpClient.py OFFLINE-ONLINE",OFFLINE-ONLINE.workingDir="/path/to/script", OFFLINE-ONLINE.command.pidfile="/path/to/pidfile"
+
+# Specify the script for ONLINE --> OFFLINE
+/helix-admin.sh --zkSvr localhost:2181 --setConfig CLUSTER clusterName ONLINE-OFFLINE.command="simpleHttpClient.py ONLINE-OFFLINE",ONLINE-OFFLINE.workingDir="/path/to/script", OFFLINE-ONLINE.command.pidfile="/path/to/pidfile"
+
+# Specify NOP for OFFLINE --> DROPPED
+/helix-admin.sh --zkSvr localhost:2181 --setConfig CLUSTER clusterName ONLINE-OFFLINE.command="nop"
+</code></pre>
+ </div>
+ <p>Like in the Java configuration, it is also possible to specify a resource scope instead of a cluster scope:</p>
+ <div class="source">
+ <pre><code># Specify the script for OFFLINE --> ONLINE
+/helix-admin.sh --zkSvr localhost:2181 --setConfig RESOURCE clusterName,resourceName OFFLINE-ONLINE.command="simpleHttpClient.py OFFLINE-ONLINE",OFFLINE-ONLINE.workingDir="/path/to/script", OFFLINE-ONLINE.command.pidfile="/path/to/pidfile"
+</code></pre>
+ </div>
+ </section>
+ </section>
+ <section>
+ <h3 id="Starting_the_Agent">Starting the Agent</h3>
+ <p>There should be an agent running for every participant you have running. Ideally, its lifecycle should match that of the participant. Here, we have a simple long-running participant called simpleHttpServer.py. Its only purpose is to record state transitions.</p>
+ <p>Here are some ways that you can start the Helix agent:</p>
+ <section>
+ <h4 id="Java">Java</h4>
+ <div class="source">
+ <pre><code>// Start your application process
+ExternalCommand serverCmd = ExternalCommand.start(workingDir + "/simpleHttpServer.py");
+
+// Start the agent
+Thread agentThread = new Thread() {
+ @Override
+ public void run() {
+ while(!isInterrupted()) {
+ try {
+ HelixAgentMain.main(new String[] {
+ "--zkSvr", zkAddr, "--cluster", clusterName, "--instanceName", instanceName,
+ "--stateModel", "OnlineOffline"
+ });
+ } catch (InterruptedException e) {
+ LOG.info("Agent thread interrupted", e);
+ interrupt();
+ } catch (Exception e) {
+ LOG.error("Exception start helix-agent", e);
+ }
+ }
+ }
+};
+agentThread.start();
+
+// Wait for the process to terminate (either intentionally or unintentionally)
+serverCmd.waitFor();
+
+// Kill the agent
+agentThread.interrupt();
+</code></pre>
+ </div>
+ </section>
+ <section>
+ <h4 id="Command_Line">Command Line</h4>
+ <div class="source">
+ <pre><code># Build Helix and start the agent
+mvn clean install -DskipTests
+chmod +x helix-agent/target/helix-agent-pkg/bin/*
+helix-agent/target/helix-agent-pkg/bin/start-helix-agent.sh --zkSvr zkAddr1,zkAddr2 --cluster clusterName --instanceName instanceName --stateModel OnlineOffline
+
+# Here, you can define your own logic to terminate this agent when your process terminates
+...
+</code></pre>
+ </div>
+ </section>
+ </section>
+ <section>
+ <h3 id="Example">Example</h3>
+ <p><a class="externalLink" href="https://git-wip-us.apache.org/repos/asf?p=helix.git;a=blob;f=helix-agent/src/test/java/org/apache/helix/agent/TestHelixAgent.java;h=ccf64ce5544207c7e48261682ea69945b71da7f1;hb=refs/heads/master">Here</a> is a basic system that uses the Helix agent package.</p>
+ </section>
+ <section>
+ <h3 id="Notes">Notes</h3>
+ <p>As you may have noticed from the examples, the participant program and the state transition program are two different programs. The former is a <i>long-running</i> process that is directly tied to the Helix agent. The latter is a process that only exists while a state transition is underway. Despite this, these two processes should be intertwined. The transition command will need to communicate to the participant to actually complete the state transition and the participant will need to communicate whether or not this was successful. The implementation of this protocol is the responsibility of the system.</p>
+ </section>
+</section>
</div>
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+
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+ <div class="span3 bottom-nav">
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- <li class="active">
- <a href="#" title="Download">Download </a>
+ <li >
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+ <li >
+ <a href="Building.html" title="Building">Building</a>
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+ <a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a>
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+ <div class="span3 bottom-nav">
+ <ul class="nav nav-list">
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- <li class="active">
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+ <li >
+ <a href="Quickstart.html" title="Quick Start">Quick Start</a>
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+ <li >
+ <a href="Tutorial.html" title="Tutorial">Tutorial</a>
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- <a href="#" title="Javadocs">Javadocs </a>
+ <li >
+ <a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a>
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+ </ul>
+ </div>
+ <div class="span3 bottom-nav">
+ <ul class="nav nav-list">
<li class="nav-header">Recipes</li>
- <li class="active">
- <a href="#" title="Distributed lock manager">Distributed lock manager </a>
+ <li >
+ <a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a>
</li>
- <li class="active">
- <a href="#" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a>
+ <li >
+ <a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a>
</li>
- <li class="active">
- <a href="#" title="Rsync replicated file store">Rsync replicated file store </a>
+ <li >
+ <a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a>
</li>
- <li class="active">
- <a href="#" title="Service discovery">Service discovery </a>
+ <li >
+ <a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a>
</li>
- <li class="active">
- <a href="#" title="Distributed task DAG execution">Distributed task DAG execution </a>
+ <li >
+ <a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a>
</li>
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+
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- <p class="copyright">Copyright ©2022 <a href="https://www.apache.org/">The Apache Software Foundation</a>. All Rights Reserved.</p>
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+ <p class="copyright">Copyright ©2023 <a href="http://www.apache.org">Apache Software Foundation</a>. All Rights Reserved.</p>
+ <p><a href="https://github.com/olamy/reflow-maven-skin" title="Reflow Maven skin">Reflow Maven skin</a> maintained by <a href="https://twitter.com/olamy" target="_blank" title="Olivier Lamy">Olivier Lamy</a>.</p>
+ <div class="row span16"><div>Apache Helix, Apache, the Apache feather logo, and the Apache Helix project logos are trademarks of The Apache Software Foundation.
+ All other marks mentioned may be trademarks or registered trademarks of their respective owners.</div>
+ <a href="https://helix.apache.org/0.9.9-docs/privacy-policy.html">Privacy Policy</a>
+ </div>
+ </div>
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+ <script src="./js/jquery.min.js"></script>
- <!-- Fallback jQuery loading from Google CDN:
- http://stackoverflow.com/questions/1014203/best-way-to-use-googles-hosted-jquery-but-fall-back-to-my-hosted-library-on-go -->
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- }
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- <!-- back button support for smooth scroll -->
- <script src="./js/jquery.ba-bbq.min.js"></script>
+ <script src="./js/bootstrap.min.js"></script>
+ <script src="./js/lightbox.min.js"></script>
+ <script src="./js/reflow-scroll.js"></script>
<script src="./js/reflow-skin.js"></script>
-
+
</body>
</html>
\ No newline at end of file
Modified: helix/site-content/0.9.9-docs/tutorial_controller.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/tutorial_controller.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/tutorial_controller.html (original)
+++ helix/site-content/0.9.9-docs/tutorial_controller.html Thu Apr 27 23:08:36 2023
@@ -1,8 +1,13 @@
<!DOCTYPE html>
+
+
+
+
+
+
<!--
- Generated by Apache Maven Doxia at 2022-04-15
- Rendered using Maven Reflow Skin 1.0.0 (http://andriusvelykis.github.com/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -13,61 +18,84 @@
<meta name="description" content="" />
<meta http-equiv="content-language" content="en" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap.min.css" rel="stylesheet" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-responsive.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap-responsive.min.css" rel="stylesheet" />
<link href="./css/docs.css" rel="stylesheet" />
<link href="./css/reflow-skin.css" rel="stylesheet" />
-
-
+
+
<link href="./css/lightbox.css" rel="stylesheet" />
-
+
<link href="./css/site.css" rel="stylesheet" />
<link href="./css/print.css" rel="stylesheet" media="print" />
-
+
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<!--[if lt IE 9]>
- <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
+ <script src="./js/html5.js"></script>
<![endif]-->
-
- </head>
- <body class="page-$config.fileId project-$config.projectId" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
+
+
+<!-- Matomo -->
+<script>
+ var _paq = window._paq = window._paq || [];
+ _paq.push(['disableCookies']);
+ _paq.push(['trackPageView']);
+ _paq.push(['enableLinkTracking']);
+
+ (function() {
+ var u="https://analytics.apache.org";
+ _paq.push(['setTrackerUrl', u+'/matomo.php']);
+ _paq.push(['setSiteId', '15']);
+ var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+ g.async=true; g.src=u+'/matomo.js'; s.parentNode.insertBefore(g,s);
+ })();
+</script>
+<!-- End Matomo Code -->
+ </head>
+
+ <body class="page-tutorial_controller project-099-docs" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
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- <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
+ <a class="btn btn-navbar" data-toggle="collapse" data-target="#top-nav-collapse">
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- <div class="nav-collapse">
+ <a class="brand" href="..">Apache Helix</a>
+ <div class="nav-collapse collapse" id="top-nav-collapse">
<ul class="nav pull-right">
- <li class="active"><a href="" title="Helix 0.9.9">Helix 0.9.9 </a></li>
- <li class="dropdown active">
+ <li ><a href="index.html" title="Helix 0.9.9">Helix 0.9.9</a></li>
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Get Helix <b class="caret"></b></a>
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- <li class="active"><a href="" title="Release Notes">Release Notes </a></li>
+ <li ><a href="download.html" title="Download">Download</a></li>
+ <li ><a href="Building.html" title="Building">Building</a></li>
+ <li ><a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a></li>
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+ <li class="dropdown">
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- <li class="active"><a href="" title="Tutorial">Tutorial </a></li>
- <li class="active"><a href="" title="Javadocs">Javadocs </a></li>
+ <li ><a href="Quickstart.html" title="Quick Start">Quick Start</a></li>
+ <li ><a href="Tutorial.html" title="Tutorial">Tutorial</a></li>
+ <li ><a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a></li>
</ul>
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- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Recipes <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Distributed lock manager">Distributed lock manager </a></li>
- <li class="active"><a href="" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a></li>
- <li class="active"><a href="" title="Rsync replicated file store">Rsync replicated file store </a></li>
- <li class="active"><a href="" title="Service discovery">Service discovery </a></li>
- <li class="active"><a href="" title="Distributed task DAG execution">Distributed task DAG execution </a></li>
+ <li ><a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a></li>
+ <li ><a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a></li>
+ <li ><a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a></li>
+ <li ><a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a></li>
+ <li ><a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a></li>
</ul>
</li>
</ul>
@@ -75,30 +103,34 @@
</div>
</div>
</div>
-
+
<div class="container">
-
+
<!-- Masthead
================================================== -->
- <header class="jumbotron subhead">
+
+ <header>
+ <div class="jumbotron subhead">
<div class="row" id="banner">
<div class="span12">
<div class="pull-left">
- <a href="" id="bannerLeft"><img src="" alt='"''"' /></a>
+ <a href="http://helix.apache.org/" id="bannerLeft"><img src="../images/helix-logo.jpg" alt='"''"' /></a>
+ <p class="lead">A cluster management framework for partitioned and replicated distributed resources</p>
</div>
<div class="pull-right">
- <a href="http://www.apache.org/" id="bannerRight"><img src="" alt='"''"' /></a>
+ <a href="http://www.apache.org/" id="bannerRight"><img src="../images/feather_small.gif" alt='"''"' /></a>
</div>
</div>
</div>
+ </div>
<div>
<ul class="breadcrumb">
- <li><a href="" title="Apache Helix">Apache Helix </a></li>
+ <li><a href="../" title="Apache Helix">Apache Helix</a></li>
<li class="divider">/</li>
- <li><a href="" title="Release 0.9.9">Release 0.9.9 </a></li>
+ <li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Tutorial - Controller</li>
- <li class="publishDate version-date pull-right">Last Published: 2022-04-15</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
@@ -107,94 +139,244 @@
<div class="row">
<div class="span12">
<div class="body-content">
-$bodyWithHeader
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<section>
+ <div class="page-header">
+ <h2 id="Helix_Tutorial:_Controller"><a href="./Tutorial.html">Helix Tutorial</a>: Controller</h2>
+ </div>
+ <p>Next, let's implement the controller. This is the brain of the cluster. Helix makes sure there is exactly one active controller running the cluster.</p>
+ <section>
+ <h3 id="Start_a_Connection">Start a Connection</h3>
+ <p>The Helix manager requires the following parameters:</p>
+ <ul>
+ <li>clusterName: A logical name to represent the group of nodes</li>
+ <li>instanceName: A logical name of the process creating the manager instance. Generally this is host:port</li>
+ <li>instanceType: Type of the process. This can be one of the following types, in this case use CONTROLLER:
+ <ul>
+ <li>CONTROLLER: Process that controls the cluster, any number of controllers can be started but only one will be active at any given time</li>
+ <li>PARTICIPANT: Process that performs the actual task in the distributed system</li>
+ <li>SPECTATOR: Process that observes the changes in the cluster</li>
+ <li>ADMIN: To carry out system admin actions</li>
+ </ul> </li>
+ <li>zkConnectString: Connection string to ZooKeeper. This is of the form host1:port1,host2:port2,host3:port3</li>
+ </ul>
+ <div class="source">
+ <pre><code>manager = HelixManagerFactory.getZKHelixManager(clusterName,
+ instanceName,
+ instanceType,
+ zkConnectString);
+</code></pre>
+ </div>
+ </section>
+ <section>
+ <h3 id="Controller_Code">Controller Code</h3>
+ <p>The Controller needs to know about all changes in the cluster. Helix takes care of this with the default implementation. If you need additional functionality, see GenericHelixController on how to configure the pipeline.</p>
+ <div class="source">
+ <pre><code>manager = HelixManagerFactory.getZKHelixManager(clusterName,
+ instanceName,
+ InstanceType.CONTROLLER,
+ zkConnectString);
+manager.connect();
+</code></pre>
+ </div>
+ <p>The snippet above shows how the controller is started. You can also start the controller using command line interface.</p>
+ <div class="source">
+ <pre><code>cd helix/helix-core/target/helix-core-pkg/bin
+./run-helix-controller.sh --zkSvr <Zookeeper ServerAddress (Required)> --cluster <Cluster name (Required)>
+</code></pre>
+ </div>
+ </section>
+ <section>
+ <h3 id="Controller_Deployment_Modes">Controller Deployment Modes</h3>
+ <p>Helix provides multiple options to deploy the controller.</p>
+ <section>
+ <h4 id="STANDALONE">STANDALONE</h4>
+ <p>The Controller can be started as a separate process to manage a cluster. This is the recommended approach. However, since one controller can be a single point of failure, multiple controller processes are required for reliability. Even if multiple controllers are running, only one will be actively managing the cluster at any time and is decided by a leader-election process. If the leader fails, another leader will take over managing the cluster.</p>
+ <p>Even though we recommend this method of deployment, it has the drawback of having to manage an additional service for each cluster. See the Controller as a Service option.</p>
+ </section>
+ <section>
+ <h4 id="EMBEDDED">EMBEDDED</h4>
+ <p>If setting up a separate controller process is not viable, then it is possible to embed the controller as a library in each of the participants.</p>
+ </section>
+ <section>
+ <h4 id="CONTROLLER_AS_A_SERVICE">CONTROLLER AS A SERVICE</h4>
+ <p>One of the cool features we added in Helix was to use a set of controllers to manage a large number of clusters.</p>
+ <p>For example if you have X clusters to be managed, instead of deploying X*3 (3 controllers for fault tolerance) controllers for each cluster, one can deploy just 3 controllers. Each controller can manage X/3 clusters. If any controller fails, the remaining two will manage X/2 clusters.</p>
+ <p>Next, let's implement the controller. This is the brain of the cluster. Helix makes sure there is exactly one active controller running the cluster.</p>
+ </section>
+ </section>
+ <section>
+ <h3 id="Start_the_Helix_agent">Start the Helix agent</h3>
+ <p>It requires the following parameters:</p>
+ <ul>
+ <li>clusterName: A logical name to represent the group of nodes</li>
+ <li>instanceName: A logical name of the process creating the manager instance. Generally this is host:port.</li>
+ <li>instanceType: Type of the process. This can be one of the following types, in this case use CONTROLLER:
+ <ul>
+ <li>CONTROLLER: Process that controls the cluster, any number of controllers can be started but only one will be active at any given time.</li>
+ <li>PARTICIPANT: Process that performs the actual task in the distributed system.</li>
+ <li>SPECTATOR: Process that observes the changes in the cluster.</li>
+ <li>ADMIN: To carry out system admin actions.</li>
+ </ul> </li>
+ <li>zkConnectString: Connection string to Zookeeper. This is of the form host1:port1,host2:port2,host3:port3.</li>
+ </ul>
+ <div class="source">
+ <pre><code> manager = HelixManagerFactory.getZKHelixManager(clusterName,
+ instanceName,
+ instanceType,
+ zkConnectString);
+</code></pre>
+ </div>
+ </section>
+ <section>
+ <h3 id="Controller_Code">Controller Code</h3>
+ <p>The Controller needs to know about all changes in the cluster. Helix takes care of this with the default implementation. If you need additional functionality, see GenericHelixController on how to configure the pipeline.</p>
+ <div class="source">
+ <pre><code> manager = HelixManagerFactory.getZKHelixManager(clusterName,
+ instanceName,
+ InstanceType.CONTROLLER,
+ zkConnectString);
+ manager.connect();
+ GenericHelixController controller = new GenericHelixController();
+ manager.addControllerListener(controller);
+ manager.addInstanceConfigChangeListener(controller);
+ manager.addResourceConfigChangeListener(controller);
+ manager.addClusterfigChangeListener(controller);
+ manager.addLiveInstanceChangeListener(controller);
+ manager.addIdealStateChangeListener(controller);
+</code></pre>
+ </div>
+ <p>The snippet above shows how the controller is started. You can also start the controller using command line interface.</p>
+ <div class="source">
+ <pre><code>cd helix/helix-core/target/helix-core-pkg/bin
+./run-helix-controller.sh --zkSvr <Zookeeper ServerAddress (Required)> --cluster <Cluster name (Required)>
+</code></pre>
+ </div>
+ </section>
+ <section>
+ <h3 id="Controller_Deployment_Modes">Controller Deployment Modes</h3>
+ <p>Helix provides multiple options to deploy the controller.</p>
+ <section>
+ <h4 id="STANDALONE">STANDALONE</h4>
+ <p>The Controller can be started as a separate process to manage a cluster. This is the recommended approach. However, since one controller can be a single point of failure, multiple controller processes are required for reliability. Even if multiple controllers are running, only one will be actively managing the cluster at any time and is decided by a leader-election process. If the leader fails, another leader will take over managing the cluster.</p>
+ <p>Even though we recommend this method of deployment, it has the drawback of having to manage an additional service for each cluster. See Controller As a Service option.</p>
+ </section>
+ <section>
+ <h4 id="EMBEDDED">EMBEDDED</h4>
+ <p>If setting up a separate controller process is not viable, then it is possible to embed the controller as a library in each of the participants.</p>
+ </section>
+ <section>
+ <h4 id="CONTROLLER_AS_A_SERVICE">CONTROLLER AS A SERVICE</h4>
+ <p>One of the cool features we added in Helix is to use a set of controllers to manage a large number of clusters.</p>
+ <p>For example if you have X clusters to be managed, instead of deploying X*3 (3 controllers for fault tolerance) controllers for each cluster, one can deploy just 3 controllers. Each controller can manage X/3 clusters. If any controller fails, the remaining two will manage X/2 clusters.</p>
+ </section>
+ </section>
+</section>
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+
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+ <li >
+ <a href="Quickstart.html" title="Quick Start">Quick Start</a>
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+ <li >
+ <a href="Tutorial.html" title="Tutorial">Tutorial</a>
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+ <li >
+ <a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a>
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+ <div class="span3 bottom-nav">
+ <ul class="nav nav-list">
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- <li class="active">
- <a href="#" title="Distributed lock manager">Distributed lock manager </a>
+ <li >
+ <a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a>
</li>
- <li class="active">
- <a href="#" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a>
+ <li >
+ <a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a>
</li>
- <li class="active">
- <a href="#" title="Rsync replicated file store">Rsync replicated file store </a>
+ <li >
+ <a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a>
</li>
- <li class="active">
- <a href="#" title="Service discovery">Service discovery </a>
+ <li >
+ <a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a>
</li>
- <li class="active">
- <a href="#" title="Distributed task DAG execution">Distributed task DAG execution </a>
+ <li >
+ <a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a>
</li>
</ul>
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+
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- </div>
+ <p class="copyright">Copyright ©2023 <a href="http://www.apache.org">Apache Software Foundation</a>. All Rights Reserved.</p>
+ <p><a href="https://github.com/olamy/reflow-maven-skin" title="Reflow Maven skin">Reflow Maven skin</a> maintained by <a href="https://twitter.com/olamy" target="_blank" title="Olivier Lamy">Olivier Lamy</a>.</p>
+ <div class="row span16"><div>Apache Helix, Apache, the Apache feather logo, and the Apache Helix project logos are trademarks of The Apache Software Foundation.
+ All other marks mentioned may be trademarks or registered trademarks of their respective owners.</div>
+ <a href="https://helix.apache.org/0.9.9-docs/privacy-policy.html">Privacy Policy</a>
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+ <script src="./js/jquery.min.js"></script>
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- <!-- back button support for smooth scroll -->
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+ <script src="./js/bootstrap.min.js"></script>
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+ <script src="./js/reflow-scroll.js"></script>
<script src="./js/reflow-skin.js"></script>
-
+
</body>
</html>
\ No newline at end of file
Modified: helix/site-content/0.9.9-docs/tutorial_health.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/tutorial_health.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/tutorial_health.html (original)
+++ helix/site-content/0.9.9-docs/tutorial_health.html Thu Apr 27 23:08:36 2023
@@ -1,8 +1,13 @@
<!DOCTYPE html>
+
+
+
+
+
+
<!--
- Generated by Apache Maven Doxia at 2022-04-15
- Rendered using Maven Reflow Skin 1.0.0 (http://andriusvelykis.github.com/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -13,61 +18,84 @@
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<meta http-equiv="content-language" content="en" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap.min.css" rel="stylesheet" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-responsive.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap-responsive.min.css" rel="stylesheet" />
<link href="./css/docs.css" rel="stylesheet" />
<link href="./css/reflow-skin.css" rel="stylesheet" />
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+ <script src="./js/html5.js"></script>
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-
- </head>
- <body class="page-$config.fileId project-$config.projectId" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
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+
+
+<!-- Matomo -->
+<script>
+ var _paq = window._paq = window._paq || [];
+ _paq.push(['disableCookies']);
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+
+ (function() {
+ var u="https://analytics.apache.org";
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+ var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+ g.async=true; g.src=u+'/matomo.js'; s.parentNode.insertBefore(g,s);
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+<!-- End Matomo Code -->
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+
+ <body class="page-tutorial_health project-099-docs" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
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<div class="navbar-inner">
<div class="container">
- <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
+ <a class="btn btn-navbar" data-toggle="collapse" data-target="#top-nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
- <div class="nav-collapse">
+ <a class="brand" href="..">Apache Helix</a>
+ <div class="nav-collapse collapse" id="top-nav-collapse">
<ul class="nav pull-right">
- <li class="active"><a href="" title="Helix 0.9.9">Helix 0.9.9 </a></li>
- <li class="dropdown active">
+ <li ><a href="index.html" title="Helix 0.9.9">Helix 0.9.9</a></li>
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Get Helix <b class="caret"></b></a>
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- <li class="active"><a href="" title="Release Notes">Release Notes </a></li>
+ <li ><a href="download.html" title="Download">Download</a></li>
+ <li ><a href="Building.html" title="Building">Building</a></li>
+ <li ><a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a></li>
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+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Hands-On <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Quick Start">Quick Start </a></li>
- <li class="active"><a href="" title="Tutorial">Tutorial </a></li>
- <li class="active"><a href="" title="Javadocs">Javadocs </a></li>
+ <li ><a href="Quickstart.html" title="Quick Start">Quick Start</a></li>
+ <li ><a href="Tutorial.html" title="Tutorial">Tutorial</a></li>
+ <li ><a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a></li>
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- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Recipes <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Distributed lock manager">Distributed lock manager </a></li>
- <li class="active"><a href="" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a></li>
- <li class="active"><a href="" title="Rsync replicated file store">Rsync replicated file store </a></li>
- <li class="active"><a href="" title="Service discovery">Service discovery </a></li>
- <li class="active"><a href="" title="Distributed task DAG execution">Distributed task DAG execution </a></li>
+ <li ><a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a></li>
+ <li ><a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a></li>
+ <li ><a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a></li>
+ <li ><a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a></li>
+ <li ><a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a></li>
</ul>
</li>
</ul>
@@ -75,30 +103,34 @@
</div>
</div>
</div>
-
+
<div class="container">
-
+
<!-- Masthead
================================================== -->
- <header class="jumbotron subhead">
+
+ <header>
+ <div class="jumbotron subhead">
<div class="row" id="banner">
<div class="span12">
<div class="pull-left">
- <a href="" id="bannerLeft"><img src="" alt='"''"' /></a>
+ <a href="http://helix.apache.org/" id="bannerLeft"><img src="../images/helix-logo.jpg" alt='"''"' /></a>
+ <p class="lead">A cluster management framework for partitioned and replicated distributed resources</p>
</div>
<div class="pull-right">
- <a href="http://www.apache.org/" id="bannerRight"><img src="" alt='"''"' /></a>
+ <a href="http://www.apache.org/" id="bannerRight"><img src="../images/feather_small.gif" alt='"''"' /></a>
</div>
</div>
</div>
+ </div>
<div>
<ul class="breadcrumb">
- <li><a href="" title="Apache Helix">Apache Helix </a></li>
+ <li><a href="../" title="Apache Helix">Apache Helix</a></li>
<li class="divider">/</li>
- <li><a href="" title="Release 0.9.9">Release 0.9.9 </a></li>
+ <li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Tutorial - Customizing Heath Checks</li>
- <li class="publishDate version-date pull-right">Last Published: 2022-04-15</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
@@ -107,94 +139,132 @@
<div class="row">
<div class="span12">
<div class="body-content">
-$bodyWithHeader
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<section>
+ <div class="page-header">
+ <h2 id="Helix_Tutorial:_Customizing_Health_Checks"><a href="./Tutorial.html">Helix Tutorial</a>: Customizing Health Checks</h2>
+ </div>
+ <p>In this chapter, we'll learn how to customize health checks based on metrics of your distributed system.</p>
+ <section>
+ <h3 id="Health_Checks">Health Checks</h3>
+ <p>Note: <i>this in currently in development mode, not yet ready for production.</i></p>
+ <p>Helix provides the ability for each node in the system to report health metrics on a periodic basis.</p>
+ <p>Helix supports multiple ways to aggregate these metrics:</p>
+ <ul>
+ <li>SUM</li>
+ <li>AVG</li>
+ <li>EXPONENTIAL DECAY</li>
+ <li>WINDOW</li>
+ </ul>
+ <p>Helix persists the aggregated value only.</p>
+ <p>Applications can define a threshold on the aggregate values according to the SLAs, and when the SLA is violated Helix will fire an alert. Currently Helix only fires an alert, but in a future release we plan to use these metrics to either mark the node dead or load balance the partitions. This feature will be valuable for distributed systems that support multi-tenancy and have a large variation in work load patterns. In addition, this can be used to detect skewed partitions (hotspots) and rebalance the cluster.</p>
+ </section>
+</section>
</div>
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+
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+ <div class="span3 bottom-nav">
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<li class="nav-header">Get Helix</li>
- <li class="active">
- <a href="#" title="Download">Download </a>
+ <li >
+ <a href="download.html" title="Download">Download</a>
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- <li class="active">
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+ <li >
+ <a href="Building.html" title="Building">Building</a>
</li>
- <li class="active">
- <a href="#" title="Release Notes">Release Notes </a>
+ <li >
+ <a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a>
</li>
+ </ul>
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+ <div class="span3 bottom-nav">
+ <ul class="nav nav-list">
<li class="nav-header">Hands-On</li>
- <li class="active">
- <a href="#" title="Quick Start">Quick Start </a>
+ <li >
+ <a href="Quickstart.html" title="Quick Start">Quick Start</a>
</li>
- <li class="active">
- <a href="#" title="Tutorial">Tutorial </a>
+ <li >
+ <a href="Tutorial.html" title="Tutorial">Tutorial</a>
</li>
- <li class="active">
- <a href="#" title="Javadocs">Javadocs </a>
+ <li >
+ <a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a>
</li>
+ </ul>
+ </div>
+ <div class="span3 bottom-nav">
+ <ul class="nav nav-list">
<li class="nav-header">Recipes</li>
- <li class="active">
- <a href="#" title="Distributed lock manager">Distributed lock manager </a>
+ <li >
+ <a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a>
</li>
- <li class="active">
- <a href="#" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a>
+ <li >
+ <a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a>
</li>
- <li class="active">
- <a href="#" title="Rsync replicated file store">Rsync replicated file store </a>
+ <li >
+ <a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a>
</li>
- <li class="active">
- <a href="#" title="Service discovery">Service discovery </a>
+ <li >
+ <a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a>
</li>
- <li class="active">
- <a href="#" title="Distributed task DAG execution">Distributed task DAG execution </a>
+ <li >
+ <a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a>
</li>
</ul>
</div>
</div>
</div>
</footer>
-
+
<div class="container subfooter">
<div class="row">
<div class="span12">
<p class="pull-right"><a href="#">Back to top</a></p>
- <p class="copyright">Copyright ©2022 <a href="https://www.apache.org/">The Apache Software Foundation</a>. All Rights Reserved.</p>
- <p><a href="http://github.com/andriusvelykis/reflow-maven-skin" title="Reflow Maven skin">Reflow Maven skin</a> by <a href="http://andrius.velykis.lt" target="_blank" title="Andrius Velykis">Andrius Velykis</a>.</p>
- </div>
+ <p class="copyright">Copyright ©2023 <a href="http://www.apache.org">Apache Software Foundation</a>. All Rights Reserved.</p>
+ <p><a href="https://github.com/olamy/reflow-maven-skin" title="Reflow Maven skin">Reflow Maven skin</a> maintained by <a href="https://twitter.com/olamy" target="_blank" title="Olivier Lamy">Olivier Lamy</a>.</p>
+ <div class="row span16"><div>Apache Helix, Apache, the Apache feather logo, and the Apache Helix project logos are trademarks of The Apache Software Foundation.
+ All other marks mentioned may be trademarks or registered trademarks of their respective owners.</div>
+ <a href="https://helix.apache.org/0.9.9-docs/privacy-policy.html">Privacy Policy</a>
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+ <script src="./js/jquery.min.js"></script>
- <!-- Fallback jQuery loading from Google CDN:
- http://stackoverflow.com/questions/1014203/best-way-to-use-googles-hosted-jquery-but-fall-back-to-my-hosted-library-on-go -->
- <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
- <script type="text/javascript">
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- document.write(unescape("%3Cscript src='./js/jquery-1.8.3.min.js' type='text/javascript'%3E%3C/script%3E"));
- }
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- <script src="./js/lightbox.js"></script>
- <script src="./js/jquery.smooth-scroll.min.js"></script>
- <!-- back button support for smooth scroll -->
- <script src="./js/jquery.ba-bbq.min.js"></script>
+ <script src="./js/bootstrap.min.js"></script>
+ <script src="./js/lightbox.min.js"></script>
+ <script src="./js/reflow-scroll.js"></script>
<script src="./js/reflow-skin.js"></script>
-
+
</body>
</html>
\ No newline at end of file
Modified: helix/site-content/0.9.9-docs/tutorial_messaging.html
URL: http://svn.apache.org/viewvc/helix/site-content/0.9.9-docs/tutorial_messaging.html?rev=1909461&r1=1909460&r2=1909461&view=diff
==============================================================================
--- helix/site-content/0.9.9-docs/tutorial_messaging.html (original)
+++ helix/site-content/0.9.9-docs/tutorial_messaging.html Thu Apr 27 23:08:36 2023
@@ -1,8 +1,13 @@
<!DOCTYPE html>
+
+
+
+
+
+
<!--
- Generated by Apache Maven Doxia at 2022-04-15
- Rendered using Maven Reflow Skin 1.0.0 (http://andriusvelykis.github.com/reflow-maven-skin)
+ Generated by Apache Maven Doxia at 2023-04-27 Rendered using Reflow Maven Skin 2.0.0 (https://olamy.github.io/reflow-maven-skin)
-->
<html xml:lang="en" lang="en">
@@ -13,61 +18,84 @@
<meta name="description" content="" />
<meta http-equiv="content-language" content="en" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap.min.css" rel="stylesheet" />
- <link href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-responsive.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap.min.css" rel="stylesheet" />
+ <link href="./css/bootstrap-responsive.min.css" rel="stylesheet" />
<link href="./css/docs.css" rel="stylesheet" />
<link href="./css/reflow-skin.css" rel="stylesheet" />
-
-
+
+
<link href="./css/lightbox.css" rel="stylesheet" />
-
+
<link href="./css/site.css" rel="stylesheet" />
<link href="./css/print.css" rel="stylesheet" media="print" />
-
+
<!-- Le HTML5 shim, for IE6-8 support of HTML5 elements -->
<!--[if lt IE 9]>
- <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
+ <script src="./js/html5.js"></script>
<![endif]-->
-
- </head>
- <body class="page-$config.fileId project-$config.projectId" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
+
+
+<!-- Matomo -->
+<script>
+ var _paq = window._paq = window._paq || [];
+ _paq.push(['disableCookies']);
+ _paq.push(['trackPageView']);
+ _paq.push(['enableLinkTracking']);
+
+ (function() {
+ var u="https://analytics.apache.org";
+ _paq.push(['setTrackerUrl', u+'/matomo.php']);
+ _paq.push(['setSiteId', '15']);
+ var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+ g.async=true; g.src=u+'/matomo.js'; s.parentNode.insertBefore(g,s);
+ })();
+</script>
+<!-- End Matomo Code -->
+ </head>
+
+ <body class="page-tutorial_messaging project-099-docs" data-spy="scroll" data-offset="60" data-target="#toc-scroll-target">
+
+
<div class="navbar navbar-fixed-top">
<div class="navbar-inner">
<div class="container">
- <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
+ <a class="btn btn-navbar" data-toggle="collapse" data-target="#top-nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
- <div class="nav-collapse">
+ <a class="brand" href="..">Apache Helix</a>
+ <div class="nav-collapse collapse" id="top-nav-collapse">
<ul class="nav pull-right">
- <li class="active"><a href="" title="Helix 0.9.9">Helix 0.9.9 </a></li>
- <li class="dropdown active">
+ <li ><a href="index.html" title="Helix 0.9.9">Helix 0.9.9</a></li>
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Get Helix <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Download">Download </a></li>
- <li class="active"><a href="" title="Building">Building </a></li>
- <li class="active"><a href="" title="Release Notes">Release Notes </a></li>
+ <li ><a href="download.html" title="Download">Download</a></li>
+ <li ><a href="Building.html" title="Building">Building</a></li>
+ <li ><a href="releasenotes/release-0.9.9.html" title="Release Notes">Release Notes</a></li>
</ul>
</li>
- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Hands-On <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Quick Start">Quick Start </a></li>
- <li class="active"><a href="" title="Tutorial">Tutorial </a></li>
- <li class="active"><a href="" title="Javadocs">Javadocs </a></li>
+ <li ><a href="Quickstart.html" title="Quick Start">Quick Start</a></li>
+ <li ><a href="Tutorial.html" title="Tutorial">Tutorial</a></li>
+ <li ><a href="../javadocs/0.9.9" title="Javadocs">Javadocs</a></li>
</ul>
</li>
- <li class="dropdown active">
+ <li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Recipes <b class="caret"></b></a>
<ul class="dropdown-menu">
- <li class="active"><a href="" title="Distributed lock manager">Distributed lock manager </a></li>
- <li class="active"><a href="" title="Rabbit MQ consumer group">Rabbit MQ consumer group </a></li>
- <li class="active"><a href="" title="Rsync replicated file store">Rsync replicated file store </a></li>
- <li class="active"><a href="" title="Service discovery">Service discovery </a></li>
- <li class="active"><a href="" title="Distributed task DAG execution">Distributed task DAG execution </a></li>
+ <li ><a href="recipes/lock_manager.html" title="Distributed lock manager">Distributed lock manager</a></li>
+ <li ><a href="recipes/rabbitmq_consumer_group.html" title="Rabbit MQ consumer group">Rabbit MQ consumer group</a></li>
+ <li ><a href="recipes/rsync_replicated_file_store.html" title="Rsync replicated file store">Rsync replicated file store</a></li>
+ <li ><a href="recipes/service_discovery.html" title="Service discovery">Service discovery</a></li>
+ <li ><a href="recipes/task_dag_execution.html" title="Distributed task DAG execution">Distributed task DAG execution</a></li>
</ul>
</li>
</ul>
@@ -75,30 +103,34 @@
</div>
</div>
</div>
-
+
<div class="container">
-
+
<!-- Masthead
================================================== -->
- <header class="jumbotron subhead">
+
+ <header>
+ <div class="jumbotron subhead">
<div class="row" id="banner">
<div class="span12">
<div class="pull-left">
- <a href="" id="bannerLeft"><img src="" alt='"''"' /></a>
+ <a href="http://helix.apache.org/" id="bannerLeft"><img src="../images/helix-logo.jpg" alt='"''"' /></a>
+ <p class="lead">A cluster management framework for partitioned and replicated distributed resources</p>
</div>
<div class="pull-right">
- <a href="http://www.apache.org/" id="bannerRight"><img src="" alt='"''"' /></a>
+ <a href="http://www.apache.org/" id="bannerRight"><img src="../images/feather_small.gif" alt='"''"' /></a>
</div>
</div>
</div>
+ </div>
<div>
<ul class="breadcrumb">
- <li><a href="" title="Apache Helix">Apache Helix </a></li>
+ <li><a href="../" title="Apache Helix">Apache Helix</a></li>
<li class="divider">/</li>
- <li><a href="" title="Release 0.9.9">Release 0.9.9 </a></li>
+ <li><a href="./" title="Release 0.9.9">Release 0.9.9</a></li>
<li class="divider">/</li>
<li>Tutorial - Messaging</li>
- <li class="publishDate version-date pull-right">Last Published: 2022-04-15</li>
+ <li class="publishDate version-date pull-right">Last Published: 2023-04-27</li>
</ul>
</div>
</header>
@@ -107,94 +139,157 @@
<div class="row">
<div class="span12">
<div class="body-content">
-$bodyWithHeader
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<section>
+ <div class="page-header">
+ <h2 id="Helix_Tutorial:_Messaging"><a href="./Tutorial.html">Helix Tutorial</a>: Messaging</h2>
+ </div>
+ <p>In this chapter, we'll learn about messaging, a convenient feature in Helix for sending messages between nodes of a cluster. This is an interesting feature that is quite useful in practice. It is common that nodes in a distributed system require a mechanism to interact with each other.</p>
+ <section>
+ <h3 id="Example:_Bootstrapping_a_Replica">Example: Bootstrapping a Replica</h3>
+ <p>Consider a search system where the index replica starts up and it does not have an index. A typical solution is to get the index from a common location, or to copy the index from another replica.</p>
+ <p>Helix provides a messaging API for intra-cluster communication between nodes in the system. This API provides a mechanism to specify the message recipient in terms of resource, partition, and state rather than specifying hostnames. Helix ensures that the message is delivered to all of the required recipients. In this particular use case, the instance can specify the recipient criteria as all replicas of the desired partition to bootstrap. Since Helix is aware of the global state of the system, it can send the message to the appropriate nodes. Once the nodes respond, Helix provides the bootstrapping replica with all the responses.</p>
+ <p>This is a very generic API and can also be used to schedule various periodic tasks in the cluster, such as data backups, log cleanup, etc. System Admins can also perform ad-hoc tasks, such as on-demand backups or a system command (such as rm -rf ;) across all nodes of the cluster</p>
+ <div class="source">
+ <pre><code>ClusterMessagingService messagingService = manager.getMessagingService();
+
+// Construct the Message
+Message requestBackupUriRequest = new Message(
+ MessageType.USER_DEFINE_MSG, UUID.randomUUID().toString());
+requestBackupUriRequest
+ .setMsgSubType(BootstrapProcess.REQUEST_BOOTSTRAP_URL);
+requestBackupUriRequest.setMsgState(MessageState.NEW);
+
+// Set the Recipient criteria: all nodes that satisfy the criteria will receive the message
+Criteria recipientCriteria = new Criteria();
+recipientCriteria.setInstanceName("%");
+recipientCriteria.setRecipientInstanceType(InstanceType.PARTICIPANT);
+recipientCriteria.setResource("MyDB");
+recipientCriteria.setPartition("");
+
+// Should be processed only by process(es) that are active at the time of sending the message
+// This means if the recipient is restarted after message is sent, it will not be processe.
+recipientCriteria.setSessionSpecific(true);
+
+// wait for 30 seconds
+int timeout = 30000;
+
+// the handler that will be invoked when any recipient responds to the message.
+BootstrapReplyHandler responseHandler = new BootstrapReplyHandler();
+
+// this will return only after all recipients respond or after timeout
+int sentMessageCount = messagingService.sendAndWait(recipientCriteria,
+ requestBackupUriRequest, responseHandler, timeout);
+</code></pre>
+ </div>
+ <p>See HelixManager.DefaultMessagingService in the <a class="externalLink" href="http://helix.apache.org/javadocs/0.9.9/reference/org/apache/helix/messaging/DefaultMessagingService.html">Javadocs</a> for more information.</p>
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