Infinispan 5 connector - ModeShape 2.8

The Infinispan 5 repository connector allows a Infinispan 5.x instance to be used as a ModeShape (and thus JCR) repository. This provides a way for the content in a repository to be stored in an effective, scalable, and distributed data grid, and can be federated with other repository sources to provide a distributed repository.

There are actually two different Infinispan connectors: one for Infinispan 4.x and one for Infinispan 5.x. Configuration and usage is basically identical, but they are in different Maven artifacts - modeshape-connector-infinispan for Infinispan 4.x, and modeshape-connector-infinispan-5 for Infinispan 5.x. (If you're using JARs, the JAR names follow the same naming pattern). Be sure your application uses the right one for the version of Infinispan you're using.)

This Infinispan 5 connector is provided so that ModeShape 2.x can be deployed into JBoss AS7, which contains Infinispan 5 by default. In can be used in other deployments, but care must be taken with the classpath and dependencies to avoid version conflicts with third-party dependencies (especially with the JPA connector, which expects to use Infinispan 4 for the second-level cache).

There are two connectors that can be used. The InfinispanSource class, which was introduced in ModeShape 1.x, stores the content in an Infinispan data grid that is running, at least in part, within the same process. The RemoteInfinispanSource class, which was introduced in ModeShape 2.3.0.Final, is capable of storing content in a remote Infinispan data grid (where Infinispan is running in remote processes). Because these two connectors communicate with Infinispan in different ways, they are configured differently.

The InfinispanSource class provides a number of JavaBean properties that control its behavior:

Property	Description
cacheContainerJndiName	Optional property that, if used, specifies the name in JNDI where an existing Infinispan Cache Manager instance can be found. That factory would then be used if needed to create an Infinispan Cache instance. If no value is provided, then the Infinispan `DefaultCacheManager` class is used. Note that the "`cacheManagerJndiName`" property is checked first as a pointer to the Infinispan `CacheManager`. If the JNDI name points to a CacheManager, the "`cacheConfigurationName`" property will not be considered.
cacheConfigurationName	Optional property that, if used, specifies the name of the configuration resource or file that is supplied to the cache manager when creating a new Infinispan DefaultCacheManager instance. The configuration name is first treated as a resource name and will be attempted to be loaded from the `ClassLoader`. If that is unsuccessful, the configuration name is assumed to be a file name and will be loaded from the file system. This initialization happens the first time that the source is used. Note that the "`cacheManagerJndiName`" property is checked first as a pointer to the Infinispan `CacheManager`. If the JNDI name points to a CacheManager, the "`cacheConfigurationName`" property will not be considered.
defaultCachePolicy	Optional property that, if used, defines the default for how long this information provided by this source may to be cached by other, higher-level components. The default value is an empty string (or null) and implies that this source does not define a specific duration for caching information provided by this repository source.
defaultWorkspaceName	Optional property that defines the name for the workspace that will be used in cases when clients do not explicitly specify the workspace name. If not specified, "`default`" will be used.
name	Required property that specifies the name of the repository source, which is used by the `RepositoryService` when obtaining a `RepositoryConnection` by name.
predefinedWorkspaceNames	Optional property that defines the names of the workspaces that exist and that are available for use without having to create them.
rootNodeUuid	Optional property that, if used, specifies the UUID that should be used for the root node of each workspace. If no value is specified, a pre-defined UUID constant is used. A custom value need only be supplied for Infinispan sources created prior to ModeShape 2.0, or if a specific UUID is desired or needed.
retryLimit	Optional property that, if used, defines the number of times that any single operation on a `RepositoryConnection` to this source should be retried following a communication failure. The default value is '0'.
updatesAllowed	Optional property that determines whether the content in the connector is can be updated ("true"), or if the content may only be read ("false"). The default value is "true".

The RemoteInfinispanSource class provides a number of JavaBean properties that control its behavior:

Property	Description
defaultCachePolicy	Optional property that, if used, defines the default for how long this information provided by this source may to be cached by other, higher-level components. The default value is an empty string (or null) and implies that this source does not define a specific duration for caching information provided by this repository source.
defaultWorkspaceName	Optional property that defines the name for the workspace that will be used in cases when clients do not explicitly specify the workspace name. If not specified, "`default`" will be used.
name	Required property that specifies the name of the repository source, which is used by the `RepositoryService` when obtaining a `RepositoryConnection` by name.
predefinedWorkspaceNames	Optional property that defines the names of the workspaces that exist and that are available for use without having to create them.
remoteInfinispanServerList	Optional property that defines the list of Infinispan HotRod servers. The list must be in the appropriate format of "`host:port[;host:port...]`" that would be used when defining an Infinispan `RemoteCacheManager` instance. If the value is missing, "`localhost:11311`" is assumed.
rootNodeUuid	Optional property that, if used, specifies the UUID that should be used for the root node of each workspace. If no value is specified, a pre-defined UUID constant is used. A custom value need only be supplied for Infinispan sources created prior to ModeShape 2.0, or if a specific UUID is desired or needed.
retryLimit	Optional property that, if used, defines the number of times that any single operation on a `RepositoryConnection` to this source should be retried following a communication failure. The default value is '0'.
updatesAllowed	Optional property that determines whether the content in the connector is can be updated ("true"), or if the content may only be read ("false"). The default value is "true".

One way to configure the Infinispan connector is to create JcrConfiguration instance with a repository source that uses the InfinispanSource class. For example:

JcrConfiguration config = ...
config.repositorySource("Infinispan Store")
      .usingClass(InfinispanSource.class)
      .setDescription("The repository for our content")
      .setProperty("defaultWorkspaceName", "prod")
      .setProperty("predefinedWorkspaceNames", new String[] { "staging", "dev"});

Another way to configure the Infinispan connector is to create JcrConfiguration instance and load an XML configuration file that contains a repository source that uses the InfinispanSource class. For example a file named configRepository.xml can be created with these contents:

<?xml version="1.0" encoding="UTF-8"?>
<configuration xmlns:mode="http://www.modeshape.org/1.0" xmlns:jcr="http://www.jcp.org/jcr/1.0">
    <!--
    Define the sources for the content.  These sources are directly accessible using the
    ModeShape-specific Graph API.  In fact, this is how the ModeShape JCR implementation works.  You
    can think of these as being similar to JDBC DataSource objects, except that they expose
    graph content via the Graph API instead of records via SQL or JDBC.
    -->
    <mode:sources jcr:primaryType="nt:unstructured">
        <!--
        The 'Infinispan Store' repository is a Infinispan repository with a single default
        workspace (though others could be created, too).
        -->
        <mode:source jcr:name="Infinispan Store"
                    mode:classname="org.modeshape.connector.infinispan.InfinispanSource"
                    mode:description="The repository for our content"
                    mode:defaultworkspaceName="prod">
           <mode:predefinedWorkspaceNames>staging</mode:predefinedWorkspaceNames>
           <mode:predefinedWorkspaceNames>dev</mode:predefinedWorkspaceNames>
        </mode:source>
    </mode:sources>

	<!-- MIME type detectors and JCR repositories would be defined below -->
</configuration>

The configuration can then be loaded from Java like this:

JcrConfiguration config = new JcrConfiguration().loadFrom("/configRepository.xml");

Considerations for Distributed SourcesThe InfinispanSource can be used to provide access to an Infinispan cluster, but be sure to use the DIST_SYNC cache mode. Using other modes will likely lead to data inconsistency. The RemoteInfinispanSource can be used to connect to an Infinispan HotRod cache server.

Additionally, some operating systems (e.g., OS X) require you to set either the java.net.preferIPv4Stack or the java.net.preferIPv6Addresses system property to true. These properties are used by JGroups, the communications library that underlies Infinispan, to help determine which address type to use.

The rootNodeUuid property must be set to the same value for all Infinispan sources in the cluster.

Considerations for using the HotRod ServerThe Infinispan HotRod Server must be made aware of the ModeShape classes that will be stored in it, since it will be running in a separate JVM. The following jar files should be added to the classpath of the HotRod Server:

modeshape-common
modeshape-graph
modeshape-connector-infinispan
joda-time

Only these libraries contain the classes that are used to store content within Infinispan.