From 19548b735da4279ccc873e1539e89fdffcd69d21 Mon Sep 17 00:00:00 2001 From: David Turanski Date: Fri, 23 Sep 2011 17:37:32 -0400 Subject: [PATCH] INT-2088 added documentation for scripting and updated groovy section --- docs/src/reference/docbook/groovy.xml | 125 ++++------------- .../reference/docbook/messaging-endpoints.xml | 3 +- docs/src/reference/docbook/scripting.xml | 126 ++++++++++++++++++ spring-integration-scripting/pom.xml | 24 ++-- 4 files changed, 166 insertions(+), 112 deletions(-) create mode 100644 docs/src/reference/docbook/scripting.xml diff --git a/docs/src/reference/docbook/groovy.xml b/docs/src/reference/docbook/groovy.xml index fd4e8df7e9..4378ee37bb 100644 --- a/docs/src/reference/docbook/groovy.xml +++ b/docs/src/reference/docbook/groovy.xml @@ -7,7 +7,7 @@ xmlns:ns="http://docbook.org/ns/docbook"> Groovy support - With Spring Integration 2.0 we've added Groovy support allowing you to + In Spring Integration 2.0 we added Groovy support allowing you to use the Groovy scripting language to provide the logic for various integration components similar to the way the Spring Expression Language (SpEL) is supported for routing, transformation and other integration @@ -17,18 +17,15 @@
Groovy configuration - - Depending on the complexity of your integration requirements Groovy - scripts could be provided inline as CDATA in XML configuration or as a - reference to a file containing the Groovy script. To enable Groovy support - Spring Integration defines a - GroovyScriptExecutingMessageProcessor which will - bind the Message Payload as a - payload variable and the Message Headers as a headers - variable within the script execution context. All that is left for you to do is - write a script that uses those - variables. Below are a couple of sample configurations: - + + With Spring Integration 2.1, Groovy Support's configuration namespace + is an extension of Spring Integration's Scripting Support and shares the core configuration + and behavior described in detail in the + Scripting Support section. Even though Groovy scripts are + well supported by generic Scripting Support, Groovy Support provides the + Groovy configuration namespace which is backed by the Spring Framework's + org.springframework.scripting.groovy.GroovyScriptFactory and related components, + offering extended capabilities for using Groovy. Below are a couple of sample configurations: Filter <int:filter input-channel="referencedScriptInput"> <int-groovy:script location="some/path/to/groovy/file/GroovyFilterTests.groovy"/> </int:filter> @@ -38,89 +35,19 @@ return payload == 'good' ]]></int-groovy:script> </int:filter> + As the above examples show, the configuration looks identical to the general Scripting Support configuration. The only + difference is the use of the Groovy namespace as indicated in the examples by the int-groovy namespace prefix. + Also note that the lang attribute on the <script> tag is not valid in this namespace. + - Here, you see that the script can be included inline - or via the location attribute using the groovy namespace - support. - - Other supported elements are router, service-activator, - transformer, and splitter. The configuration would look identical to that - above other than the main element's name. - - Another interesting aspect of using Groovy support is the framework's - ability to update (reload) scripts without restarting the Application - Context. To accomplish this, all you need to do is specify - the refresh-check-delay attribute on the script - element. - - <int-groovy:script location="..." refresh-check-delay="5000"/> - - In the above example any invocations that occur within the 5 seconds immediately following the - updating of the script would still be using the old script. However, any invocation that occurs - after those 5 seconds have elapsed will - result in execution of the new script. This is a good example where 'near real - time' is acceptable. - - <int-groovy:script location="..." refresh-check-delay="0"/> - - In the above example the context will be updated with any script modifications - as soon as such modification occurs. Basically this is an example of - 'real-time' configuration and might not be the most efficient option (but could be useful during development). - - <int-groovy:script location="..." refresh-check-delay="-1"/> - - Any negative number value means the script will never be refreshed after - initial initialization of the application context. This is the default behavior. - In this case, the "dynamic" aspect of Groovy is not being used, but the syntax - might be the primary reason that Groovy has been chosen in the first place. - Inline defined scripts can not be reloaded. + + Groovy object customization - Custom bindings - - - You already know that by default, 'payload' and 'headers' will be bound as Groovy binding variables. - However, some times in order to take the most out of Groovy you may want to customize Groovy bindings - (e.g., include extra variables pointing to some scalar values or bind some beans as variables). - To support this requirement we have defined a simple strategy: ScriptVariableGenerator. - generateScriptVariables(Message message); - -}]]> - - As you can see the only method to implement is generateScriptVariables(Message). It takes the Message - as an argument. That allows you to use data available in the Message payload and/or headers. The return value is - the Map of variables that will be bound to the script's evaluation context. This method will be called every time - the script is executed, corresponding to the processing of that particular Message. We also provide a - default implementation and namespace based configuration for simple bindings via <variable> sub-elements (see below): - - - - -]]> - - As you can see similar to other constructs in Spring, when binding each of these variables you can either provide a - scalar value or reference another bean in the Application Context. - - - If you need more control over how a particular variable is generated, then all you need to do is - provide your own implementation of ScriptVariableGenerator and reference it with the script-variable-generator - attribute: - - -]]> - - - The script-variable-generator attribute and <variable> sub-element(s) are mutually exclusive. - You can use at most one of them. Also, the script-variable-generator and <variable> sub-elements - cannot be used with an inline script, but rather only when pointing to the script via the location attribute. - - + If you need to customize the Groovy object itself, beyond setting variables, you can reference - a bean that implementats org.springframework.scripting.groovy.GroovyObjectCustomizer via the - customizer attribute. For example, this might be useful if you want to configure a domain-specific - language (DSL) by modifying the MetaClass and registering functions to be available within the script. + a bean that implements org.springframework.scripting.groovy.GroovyObjectCustomizer via the + customizer attribute. For example, this might be useful if you want to implement a domain-specific + language (DSL) by modifying the MetaClass and registering functions to be available within the script: @@ -128,7 +55,7 @@ ]]> - Setting a custom GroovyObjectCustomizer is not mutually exclusive with <variable> sub-elements or + Setting a custom GroovyObjectCustomizer is not mutually exclusive with <variable> sub-elements or the script-variable-generator attribute. It can also be provided when defining an inline script.
@@ -150,15 +77,15 @@ The Groovy Control Bus executes messages on the input channel as Groovy scripts. It takes a message, compiles the body to a Script, - customizes it with a GroovyObjectCustomizer, and then executes it. The + customizes it with a GroovyObjectCustomizer, and then executes it. The Control Bus' customizer exposes all the beans in the application context - that are annotated with @ManagedResource, implement Spring's - Lifecycle interface or extend Spring's CustomizableThreadCreator base class - (e.g. several of the TaskExecutor and TaskScheduler implementations). + that are annotated with @ManagedResource, implement Spring's + Lifecycleinterface or extend Spring's CustomizableThreadCreator base class + (e.g. several of the TaskExecutor and TaskScheduler implementations). If you need to further customize the Groovy objects, you can also provide a reference to a bean - that implements org.springframework.scripting.groovy.GroovyObjectCustomizer via + that implements org.springframework.scripting.groovy.GroovyObjectCustomizer via the customizer attribute. - + + diff --git a/docs/src/reference/docbook/scripting.xml b/docs/src/reference/docbook/scripting.xml new file mode 100644 index 0000000000..bfa8777bd5 --- /dev/null +++ b/docs/src/reference/docbook/scripting.xml @@ -0,0 +1,126 @@ + +
+ Scripting support + + With Spring Integration 2.1 we've added support for the + JSR223 Scripting for Java specification, + introduced in Java version 6. This allows you to use scripts written in any supported language including + Ruby/JRuby, Javascript and Groovy to provide the logic for various integration components similar to the way + the Spring Expression Language (SpEL) is used in Spring Integration. For more information about JSR223 please refer to the + documentation + + Note that this feature requires Java 6 or higher. Sun developed a JSR223 reference implementation which works with + Java 5 but it is not officially supported and we have not tested it with Spring Integration. + + + + In order to use a JVM scripting language, a JSR223 implementation for that language must be included in your class path. Java 6 natively + supports Javascript. The Groovy and + JRuby projects provide JSR233 support in their standard distribution. + Other language implementations may be available or under development. Please refer to the appropriate project website for more information. + + Various JSR223 language implementations have been developed by third parties. A particular implementation's compatibility + with Spring Integration depends on how well it conforms to the specification and/or the implementer's interpretation of the specification. + + If you plan to use Groovy as your scripting language, we recommended you use Spring-Integration's Groovy Support + as it offers additional features specific to Groovy. However you will find his section relevant as well. + + + +
+ Script configuration + + Depending on the complexity of your integration requirements + scripts may be provided inline as CDATA in XML configuration or as a + reference to a Spring resource containing the script. To enable scripting support + Spring Integration defines a + ScriptExecutingMessageProcessor which will + bind the Message Payload to a + variable named payload and the Message Headers to a headers + variable, both accessible within the script execution context. All that is left for you to do is + write a script that uses these variables. Below are a couple of sample configurations: + + Filter <int:filter input-channel="referencedScriptInput"> + <int-script:script lang="ruby" location="some/path/to/ruby/script/RubyFilterTests.rb"/> +</int:filter> + +<int:filter input-channel="inlineScriptInput"> + <int-script:script lang="groovy"><![CDATA[ + return payload == 'good' + ]]></int-script:script> +</int:filter> + + Here, you see that the script can be included inline + or can reference a resource location via the location attribute. Additionally the lang attribute + corresponds to the language name (or JSR223 alias) + + Other Spring Integration endpoint elements which support scripting include router, service-activator, + transformer, and splitter. The scripting configuration in each case would be identical to the above + (besides the endpoint element). + + + Another useful feature of Scripting support is the ability to update (reload) scripts without + having to restart the Application Context. To accomplish this, specify the refresh-check-delay + attribute on the script element: + + <int-script:script location="..." refresh-check-delay="5000"/> + + In the above example, the script location will be checked for updates every 5 seconds. If the script is updated, + any invocation that occurs later than 5 seconds since the update will result in execution of the new script. + + <int-script:script location="..." refresh-check-delay="0"/> + + In the above example the context will be updated with any script modifications + as soon as such modification occurs, providing a simple mechanism for 'real-time' configuration. + + Any negative number value means the script will not be reloaded after initialization of the application context. + This is the default behavior. Inline scripts can not be reloaded. + + <int-script:script location="..." refresh-check-delay="-1"/> + + Script variable bindings + + + Variable bindings are required to enable the script to reference variables externally provided to the script's execution context. + As we have seen, payload and headers are used as binding variables by default. You can bind additional variables + to a script via <variable> sub-elements: + + + + +]]> + As shown in the above example, you can bind a script variable either to a scalar value or a Spring bean reference. Note that + payload and headers will still be included as binding variables. + + + + If you need more control over how variables are generated, you can implement your own Java class + using the ScriptVariableGenerator strategy: + generateScriptVariables(Message message); + +}]]> + + This interface requires you to implement the method generateScriptVariables(Message). The Message + argument allows you to access any data available in the Message payload and headers and the return value is + the Map of bound variables. This method will be called every time the script is executed for a Message. All you need to do is + provide an implementation of ScriptVariableGenerator and reference it with the script-variable-generator + attribute: + + +]]> + + + You cannot provide both the script-variable-generator attribute and <variable> sub-element(s) + as they are mutually exclusive. Also, custom variable bindings cannot be used with an inline script. + + +
+
diff --git a/spring-integration-scripting/pom.xml b/spring-integration-scripting/pom.xml index 89c3d77d2e..0d55c53ab9 100644 --- a/spring-integration-scripting/pom.xml +++ b/spring-integration-scripting/pom.xml @@ -88,30 +88,24 @@ + + org.springframework.integration + spring-integration-core + 2.1.0.BUILD-SNAPSHOT + compile + org.easymock easymock 2.3 test - - org.springframework.integration - spring-integration-test - 2.1.0.BUILD-SNAPSHOT - test - org.easymock easymockclassextension 2.3 test - - org.springframework.integration - spring-integration-core - 2.1.0.BUILD-SNAPSHOT - compile - org.hamcrest hamcrest-all @@ -136,6 +130,12 @@ 1.7.5 test + + org.springframework.integration + spring-integration-test + 2.1.0.BUILD-SNAPSHOT + test + log4j log4j