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Posted to commits@camel.apache.org by ac...@apache.org on 2016/05/05 12:07:27 UTC
[3/4] camel git commit: Added Camel-LevelDB docs to Gitbook
Added Camel-LevelDB docs to Gitbook
Project: http://git-wip-us.apache.org/repos/asf/camel/repo
Commit: http://git-wip-us.apache.org/repos/asf/camel/commit/9aa27a3b
Tree: http://git-wip-us.apache.org/repos/asf/camel/tree/9aa27a3b
Diff: http://git-wip-us.apache.org/repos/asf/camel/diff/9aa27a3b
Branch: refs/heads/master
Commit: 9aa27a3b7a22b382442a98639fb8a7ffd13c8d89
Parents: d83af66
Author: Andrea Cosentino <an...@gmail.com>
Authored: Thu May 5 13:37:40 2016 +0200
Committer: Andrea Cosentino <an...@gmail.com>
Committed: Thu May 5 13:37:40 2016 +0200
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.../camel-leveldb/src/main/docs/leveldb.adoc | 171 +++++++++++++++++++
docs/user-manual/en/SUMMARY.md | 1 +
2 files changed, 172 insertions(+)
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http://git-wip-us.apache.org/repos/asf/camel/blob/9aa27a3b/components/camel-leveldb/src/main/docs/leveldb.adoc
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diff --git a/components/camel-leveldb/src/main/docs/leveldb.adoc b/components/camel-leveldb/src/main/docs/leveldb.adoc
new file mode 100644
index 0000000..17351d6
--- /dev/null
+++ b/components/camel-leveldb/src/main/docs/leveldb.adoc
@@ -0,0 +1,171 @@
+[[LevelDB-LevelDB]]
+LevelDB
+~~~~~~~
+
+*Available as of Camel 2.10*
+
+https://code.google.com/p/leveldb/[Leveldb] is a very lightweight and
+embedable key value database. It allows together with Camel to provide
+persistent support for various Camel features such as
+link:aggregator2.html[Aggregator].
+
+Current features it provides:
+
+* LevelDBAggregationRepository
+
+[[LevelDB-UsingLevelDBAggregationRepository]]
+Using LevelDBAggregationRepository
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+`LevelDBAggregationRepository` is an `AggregationRepository` which on
+the fly persists the aggregated messages. This ensures that you will not
+loose messages, as the default aggregator will use an in memory only
+`AggregationRepository`.
+
+It has the following options:
+
+[width="100%",cols="10%,10%,80%",options="header",]
+|=======================================================================
+
+|Option |Type |Description
+
+|`repositoryName` |String |A mandatory repository name. Allows you to use a shared `LevelDBFile`
+for multiple repositories.
+
+|`persistentFileName` |String |Filename for the persistent storage. If no file exists on startup a new
+file is created.
+
+|`levelDBFile` |LevelDBFile |Use an existing configured
+`org.apache.camel.component.leveldb.LevelDBFile` instance.
+
+|`sync` |boolean |*Camel 2.12:* Whether or not the LevelDBFile should sync on write or
+not. Default is false. By sync on write ensures that its always waiting
+for all writes to be spooled to disk and thus will not loose updates.
+See http://leveldb.googlecode.com/svn/trunk/doc/index.html[LevelDB docs]
+for more details about async vs sync writes.
+
+|`returnOldExchange` |boolean |Whether the get operation should return the old existing Exchange if any
+existed. By default this option is `false` to optimize as we do not need
+the old exchange when aggregating.
+
+|`useRecovery` |boolean |Whether or not recovery is enabled. This option is by default `true`.
+When enabled the Camel link:aggregator2.html[Aggregator] automatic
+recover failed aggregated exchange and have them resubmitted.
+
+|`recoveryInterval` |long |If recovery is enabled then a background task is run every x'th time to
+scan for failed exchanges to recover and resubmit. By default this
+interval is 5000 millis.
+
+|`maximumRedeliveries` |int |Allows you to limit the maximum number of redelivery attempts for a
+recovered exchange. If enabled then the Exchange will be moved to the
+dead letter channel if all redelivery attempts failed. By default this
+option is disabled. If this option is used then the `deadLetterUri`
+option must also be provided.
+
+|`deadLetterUri` |String |An endpoint uri for a link:dead-letter-channel.html[Dead Letter Channel]
+where exhausted recovered Exchanges will be moved. If this option is
+used then the `maximumRedeliveries` option must also be provided.
+|=======================================================================
+
+The `repositoryName` option must be provided. Then either the
+`persistentFileName` or the `levelDBFile` must be provided.
+
+[[LevelDB-Whatispreservedwhenpersisting]]
+What is preserved when persisting
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+`LevelDBAggregationRepository` will only preserve any `Serializable`
+compatible message body data types. Message headers must be primitive /
+string / numbers / etc. If a data type is not such a type its dropped
+and a `WARN` is logged. And it only persists the `Message` body and the
+`Message` headers. The `Exchange` properties are *not* persisted.
+
+[[LevelDB-Recovery]]
+Recovery
+^^^^^^^^
+
+The `LevelDBAggregationRepository` will by default recover any failed
+link:exchange.html[Exchange]. It does this by having a background tasks
+that scans for failed link:exchange.html[Exchange]s in the persistent
+store. You can use the `checkInterval` option to set how often this task
+runs. The recovery works as transactional which ensures that Camel will
+try to recover and redeliver the failed link:exchange.html[Exchange].
+Any link:exchange.html[Exchange] which was found to be recovered will be
+restored from the persistent store and resubmitted and send out again.
+
+The following headers is set when an link:exchange.html[Exchange] is
+being recovered/redelivered:
+
+[width="100%",cols="10%,10%,80%",options="header",]
+|=======================================================================
+|Header |Type |Description
+
+|`Exchange.REDELIVERED` |Boolean |Is set to true to indicate the link:exchange.html[Exchange] is being
+redelivered.
+
+|`Exchange.REDELIVERY_COUNTER` |Integer |The redelivery attempt, starting from 1.
+|=======================================================================
+
+Only when an link:exchange.html[Exchange] has been successfully
+processed it will be marked as complete which happens when the `confirm`
+method is invoked on the `AggregationRepository`. This means if the same
+link:exchange.html[Exchange] fails again it will be kept retried until
+it success.
+
+You can use option `maximumRedeliveries` to limit the maximum number of
+redelivery attempts for a given recovered link:exchange.html[Exchange].
+You must also set the `deadLetterUri` option so Camel knows where to
+send the link:exchange.html[Exchange] when the `maximumRedeliveries` was
+hit.
+
+You can see some examples in the unit tests of camel-leveldb, for
+example
+https://svn.apache.org/repos/asf/camel/trunk/components/camel-leveldb/src/test/java/org/apache/camel/component/leveldb/LevelDBAggregateRecoverTest.java[this
+test].
+
+[[LevelDB-UsingLevelDBAggregationRepositoryinJavaDSL]]
+Using LevelDBAggregationRepository in Java DSL
+++++++++++++++++++++++++++++++++++++++++++++++
+
+In this example we want to persist aggregated messages in the
+`target/data/leveldb.dat` file.
+
+[[LevelDB-UsingLevelDBAggregationRepositoryinSpringXML]]
+Using LevelDBAggregationRepository in Spring XML
+++++++++++++++++++++++++++++++++++++++++++++++++
+
+The same example but using Spring XML instead:
+
+[[LevelDB-Dependencies]]
+Dependencies
+^^^^^^^^^^^^
+
+To use link:leveldb.html[LevelDB] in your camel routes you need to add
+the a dependency on *camel-leveldb*.
+
+If you use maven you could just add the following to your pom.xml,
+substituting the version number for the latest & greatest release (see
+link:download.html[the download page for the latest versions]).
+
+[source,xml]
+----------------------------------------
+<dependency>
+ <groupId>org.apache.camel</groupId>
+ <artifactId>camel-leveldb</artifactId>
+ <version>2.10.0</version>
+</dependency>
+----------------------------------------
+
+[[LevelDB-SeeAlso]]
+See Also
+^^^^^^^^
+
+* link:configuring-camel.html[Configuring Camel]
+* link:component.html[Component]
+* link:endpoint.html[Endpoint]
+* link:getting-started.html[Getting Started]
+
+* link:aggregator2.html[Aggregator]
+* link:hawtdb.html[HawtDB]
+* link:components.html[Components]
+
http://git-wip-us.apache.org/repos/asf/camel/blob/9aa27a3b/docs/user-manual/en/SUMMARY.md
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diff --git a/docs/user-manual/en/SUMMARY.md b/docs/user-manual/en/SUMMARY.md
index 86f524d..5cad8b7 100644
--- a/docs/user-manual/en/SUMMARY.md
+++ b/docs/user-manual/en/SUMMARY.md
@@ -182,6 +182,7 @@
* [Kubernetes](kubernetes.adoc)
* [Kura](kura.adoc)
* [LDAP](ldap.adoc)
+ * [LevelDB](leveldb.adoc)
* [Metrics](metrics.adoc)
* [Mock](mock.adoc)
* [NATS](nats.adoc)