Add support for any 'outbound-channel-adapter' as end-MessageHandler of the <chain> [INT-2275]

[spring-operator]

Piotr Dyraga opened INT-2275 and commented

When I try to define service activator as a chain element using namespace support, exception is raised.
For example, the following definition does not work:

<int:chain input-channel="input">
  <int:header-enricher>
    <int:header name="file_name" value="myfile.txt" />
  </int:header-enricher>
  <file:outbound-channel-adapter id="fileWriter" directory="/tmp" />
</int:chain>

When I do the same using plain bean definition (not using namespaces), everything is fine:

<int:chain input-channel="input">
    <int:header-enricher>
      <int:header name="file_name" value="myfile.txt" />
    </int:header-enricher>
    <int:service-activator ref="fileWritingMessageHandler"
      method="handleMessage" />
  </int:chain>

  <bean id="fileWritingMessageHandler"
    class="org.springframework.integration.file.FileWritingMessageHandler">
    <constructor-arg value="/tmp" />

    <property name="fileNameGenerator">
      <bean class="org.springframework.integration.file.DefaultFileNameGenerator">
        <property name="headerName" value="file_name" />
      </bean>
    </property>
    <property name="outputChannel" ref="nullChannel" />
  </bean>

Exactly the same situation is for other activators, for example int-event:outbound-channel-adapter.
I've enclosed sample maven project reproducing this issue: try to run "FailingTest" and "WorkingTest".

Exception:

java.lang.IllegalStateException: Failed to load ApplicationContext
	at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:308)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:109)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:75)
	at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:321)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:220)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:301)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:303)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:240)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:180)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.integration.handler.MessageHandlerChain#0': Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.util.ArrayList' to required type 'java.util.List' for property 'handlers'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [org.springframework.integration.endpoint.EventDrivenConsumer] to required type [org.springframework.integration.core.MessageHandler] for property 'handlers[1]': no matching editors or conversion strategy found
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:527)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
	at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:84)
	at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:1)
	at org.springframework.test.context.TestContext.loadApplicationContext(TestContext.java:280)
	at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:304)
	... 24 more
Caused by: org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.util.ArrayList' to required type 'java.util.List' for property 'handlers'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [org.springframework.integration.endpoint.EventDrivenConsumer] to required type [org.springframework.integration.core.MessageHandler] for property 'handlers[1]': no matching editors or conversion strategy found
	at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:462)
	at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:499)
	at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:493)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1371)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1330)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1086)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
	... 36 more
Caused by: java.lang.IllegalStateException: Cannot convert value of type [org.springframework.integration.endpoint.EventDrivenConsumer] to required type [org.springframework.integration.core.MessageHandler] for property 'handlers[1]': no matching editors or conversion strategy found
	at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:231)
	at org.springframework.beans.TypeConverterDelegate.convertToTypedCollection(TypeConverterDelegate.java:520)
	at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:173)
	at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:447)
	... 42 more

---

Affects: 2.0.5

Attachments:

• issue.tar.gz (1.75 kB)

Issue Links:

• Improve XSD Schema: Inside a Chain Components cannot have a Poller sub-element [INT-2218] #6200 Improve XSD Schema: Inside a Chain Components cannot have a Poller sub-element

1 votes, 2 watchers

[spring-operator]

Artem Bilan commented

Piotr, as you can see in the StackTrace +only+ instances of org.springframework.integration.core.MessageHandler can be defined inside <chain>.
So, in your sample file:outbound-channel-adapter doesn't implement MessageHandler, but int:service-activator does.

Have you got any other questions?

[spring-operator]

Mark Fisher commented

I updated the description to mention "outbound-channel-adapter" as the limitation. For now, it should be defined outside of the chain and connected via the chain's "output-channel". In 2.2, we'll add support for the channel-adapter to appear in the chain, but it will only be allowed as the last element (similar to the way routers are allowed today).

[spring-operator]

Artem Bilan commented

Mark, then it is New Feature, not a Bug. Exception message clearly says where the programmer was not right.
And also, as you know, all router components are MessageHandler, so they are easily inserted into the <chain>...

[spring-operator]

Oleg Zhurakousky commented

file:outbound-channel-adapter is FileWritingMessageHandler

[spring-operator]

Artem Bilan commented

file:outbound-channel-adapter is FileWritingMessageHandler

Yes, but look into FileOutboundChannelAdapterParser and follow how it parses its tag and what it produces in the end - EventDrivenConsumer

[spring-operator]

Oleg Zhurakousky commented

And we need to fix whatever it is we are doing. It might not be easy (probably isn't), but it is a valid concern.
Personally I am not a big fan of chains, but they do provide certain level of grouping message flows and we should support inclusion of the outbound adapters as the last element in the chain.

[spring-operator]

Artem Bilan commented

So, let me try to implement this solution!
I am a fan of chains ;-). They allow to avoid 'Too Many Channels' pain.

[spring-operator]

Piotr Dyraga commented

Stack trace is clear for me, but as a developer working with SI, I'd expect that file:outbound-channel-adapter produces FileWritingMessageHandler which implements MessageHandler (extends AbstractMessageHandler). So in my opinion it is parser issue.

[spring-operator]

Artem Bilan commented

Link with #6200
Adding any 'outbound-channel-adapter' to the end of <chain> needs some improvement in XSD.

[spring-operator]

Mark Fisher commented

Any update on the status of this resolution? I noticed that we have an example in Spring Integration in Action that uses a mail:outbound-channel-adapter as the last element in a <chain>. I'd prefer not to change the example in the book (since it should be possible) but rather to have this issue resolved by the time the book hits the shelves ;)

[spring-operator]

Artem Bilan commented

Mark, I'm working on it. A couple later I am notifying you of the situation.
Can you show me that sample from Spring Integration in Action? And I try it.
Believe me: right now it doesn't work ;-):

<int:chain input-channel="adapterInsideChain">
    <int-mail:outbound-channel-adapter mail-sender="mailSender"/>
</int:chain>

Exception:

org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: The channel-adapter's 'id' attribute is required when no 'channel' reference has been provided, because that 'id' would be used for the created channel.

Nevertheless when I provide 'id' for adapter I catch:

java.lang.IllegalStateException: Cannot convert value of type [org.springframework.integration.endpoint.EventDrivenConsumer] to required type [org.springframework.integration.core.MessageHandler] for property 'handlers[0]': no matching editors or conversion strategy found

maybe it worked in 1.x.x?
However it is initial implementation: artembilan@3a7a1e1#diff-6
There are problems with some outbound-adapters' handlers, which aren't 'outbound' by their architecture: they implements MessageProducer
You can see some trick in my tests: artembilan@3a7a1e1#L14R17

[spring-operator]

Mark Fisher commented

Artem, here is the example from the book:

<chain input-channel="passengers">
  <transformer ref="frequentFlyerService" method="configureProfile"/>
  <mail:header-enricher>
    <mail:to expression="payload.emailAddress"/>
  </mail:header-enricher>
  <mail:outbound-channel-adapter mail-sender="mailSender"/>
</chain>

[spring-operator]

Oleg Zhurakousky commented

Artem

What are the chances of this being done today?

[spring-operator]

Artem Bilan commented

Hello, Oleg
I'm working under it right now struggles.
Now I'm just writing tests throughout the project.
But as I emailed in the integration-dev it is more about ignored tests.
So, maybe can I make PR and other tests about 'OCA within chain' should be done in the separetes JIRAs for refactoring later?
However I want to say that there are a lot of changes...

[spring-operator]

Artem Bilan commented

Issued PR: #435