<gateway id="testService" service-interface="org.example.TestService"
default-request-channel="requestChannel"/>
public interface TestService {
void placeOrder(Order order);
}
<int:router input-channel="requestchannel" expression="payload.name">
<int:mapping value="foo" channel="channel_one" />
....
</int:router>
<int:chain input-channel="channel_one" output-channel="channel_default" >
<int:gateway request-channel="chainC" error-channel="errChannel"/>
<int:filter expression="headers['Release'] != null" discard-channel="nullChannel"/>
</int:chain>
There are two paths in this chain - success path moving to channel_default and error path moving to null channel.
Can this gateway cause a memory leak. How do I check that? Is there any way to ensure that the threads initiated for handling gateway requests are released after some time.
If the flow downstream of channel chainC might not return a reply, you need to set the reply-timeout to release the thread which will otherwise hang waiting for a reply that will never come.
As long as you have no async handoffs in that subflow, it is safe to set reply-timeout="0", because, in that case, the timer doesn't start until the subflow completes.
If chainC always returns a result, or exception, there is no possibility of a memory leak with that configuration.
Related
Below is code snippets, where I am trying to handle an error.
<int:channel id="errorGateWayChannel"></int:channel>
<int:service-activator ref="errorHandler"
input-channel="errorGateWayChannel" />
...
<int:service-activator.. />
<int-http:outbound-gateway ..>
<int:channel id="routerInputChannel">
<int:dispatcher task-executor="sharedPool"/></int:channel>
<int:header-enricher input-channel="routerInputChannel" output-channel="routerInputChannel1">
<int:error-channel ref="errorGateWayChannel"/>
</int:header-enricher>
<int:recipient-list-router input-channel="routerInputChannel1"
default-output-channel="nullChannel">
<int:recipient channel="datasetInputChannel"/>
</int:recipient-list-router>
<int:service-activator id="datasetInputChannelSA" input-channel="datasetInputChannel"/> <!-- now this service activator giving me error -->
Now if "datasetInputChannelSA" service activator throw any exception I am getting WARN and that not propagate to error channel.
WARN org.springframework.messaging.core.GenericMessagingTemplate$TemporaryReplyChannel - Reply message received but the receiving thread has already received a reply:ErrorMessage [payload=org.springframework.messaging.MessageHandlingException: nested exception is java.lang.RuntimeException:
I can see similar threads where they are getting WARN but not found how to handle it.
Update:
After providing overwrite="true" in "int:error-channel" it is working and sovle my issue.
<int:error-channel ref="errorGateWayChannel"/>
to
<int:error-channel ref="errorGateWayChannel" overwrite="true"/>
Your configuration is not full enough to play with on our side, so, would be great to have some small project from you somewhere on GitHub to let us to reproduce an issue if that.
However, if you would like to handle errors from the datasetInputChannelSA and don't have any other problems, you need to consider to use a <request-handler-advice-chain> for that <service-activator> and include an ExpressionEvaluatingRequestHandlerAdvice with its trapException as true. There you can configure a failureChannel to catch service exceptions and handle them in the consumer of that channel: https://docs.spring.io/spring-integration/docs/current/reference/html/#expression-advice
It's already late to set a error-channel header in an Executor context: the failed message is not going to consult downstream headers. So, your error is propagated to the TemporaryReplyChannel header populated by the upstream gateway call (not shown in your code snippet though...).
I am trying to design a message processing pipeline that needs to process a message using multiple end-points. At each stage, the endpoints returns either the payload (could be transformed) or an error message. Here's a generic example of what I have in my mind:
<int:payload-type-router input-channel="preprocessing-output">
<int:mapping type="com.example.Error" channel="error" />
<int:mapping type="com.example.PreprocessedDomainObject" channel="validation-input"/>
</int:payload-type-router>
<int:service-activator input-channel="validation-input"
ref="validationService" method="validate" output-channel="validation-output"/>
<int:payload-type-router input-channel="validation-output">
<int:mapping type="com.example.Error" channel="error" />
<int:mapping type="com.example.CouldBeAnotherObject" channel="processor-input"/>
</int:payload-type-router>
So on, this processing chain can be quite long... Is there a better way to design this instead of a payload type router after every stage? Kinda feels redundant.
Well, I'd make it based on the exceptions. The validation service should just throw exception and all you need is to catch it on the caller or have an errorChannel if it is Inbound Channel Adapter.
That way you don't need those routers definitions at all and just plain services calling chain.
I have issue with reply-timeout property of StoredProcOutboundGateway in spring integration. I have gone through the documentation and it says reply-time out will not work in case of direct channel for the Gateway . But in case of external integration gateways ie StoredProcOutboundGateway it says
"when sending to a DirectChannel, the invocation will occur in the sender’s thread so the failing of the send operation may be caused by other components further downstream "
As per my design my StoredProcOutboundGateway reply is sending to a Direct channel.Will the StoredProcOutboundGateway throw exception after the reply-time out expiration ? .For re creating this scenario I have put a debug point and wait for configured reply time out in the first line of StoredProcOutboundGateway.handleRequestMessage method ,But it didn't thrown any exception and it returned successsful response even after configured time .
<int:gateway id="idGateway" service-interface="Gateway">
<int:method name="getStoreProcData" request-channel="store.req.channel" reply-channel="store.reply.channel" />
</int:gateway>
<int-jdbc:stored-proc-outbound-gateway stored-procedure-name="GE_PKG.GET_PRC"
ignore-column-meta-data="true" reply-timeout="2000" request-channel="store.req.channel" reply-channel="store.reply.channel" is-function="false"
............other cursor config
</int-jdbc:stored-proc-outbound-gateway>enter code here
<int:channel id="store.req.channel" />
<int:channel id="store.reply.channel" />
Spring-Integration V4..1.2 DB oracle ojdbc6
The reply-timeout only applies if the reply-channel can block - such as a bounded QueueChannel that is full.
i.e. it is a timeout for the send to the reply-channel.
It will never occur with a DirectChannel.
I have the following workflow.
inbound-channel
splitter
task executor for split channels - all the threads execute the same workflow.
3.a. construct the request
3.b. service activator wrapper for a gateway message endpoint.
3.c. gateway wrapper over the http-outbound-gateway with the configuration of error-channel (to handle exceptions while invoking http-outbound-gateway)
3.d. http-outbound-gateway
aggregator
response out of spring integration workflow.
If an exception occurs in 3.d, the control goes to the service-activator configured for the gateway error channel.
I copy just the following from the failed message to the new header to the header passed to the error channel.
a. correlationId
b. sequenceNumber
c. sequenceSize
But while aggregating the splitter response, the DefaultAggregatingMessageGroupProcessor.java removes the conflicting headers and by that it removes the error-channel and reply-channel before providing the control to aggregator.
So once the aggregator completes it's operation it is unable to find the reply or error channel and it results in an exception.
I'm using spring-integration-core version 2.2.1 and I'm not sure why the reply-channel and error-channel is being removed during header aggregation.
Any input on resolving this issue will be of great help.
Thank You :)
EDIT 1:
Thank You very much Gary for helping me out with this scenario. I'm sharing my current configuration
<!-- SPLITTER -->
<int:splitter id="dentalSplitter" ref="dentalServiceSplitter"
method="getDentalServiceList" input-channel="dentalServiceSplitterChannel"
output-channel="dentalSplitterTaskChannel" />
<int:channel id="dentalSplitterTaskChannel">
<int:dispatcher task-executor="dentalTaskExecutor" />
</int:channel>
<int:chain input-channel="dentalSplitterTaskChannel" output-channel="dentalGatewayChannel">
<int:header-enricher>
<int:header name="CHAIN_START_TIME" expression="T(System).currentTimeMillis()" overwrite="true" />
<int:object-to-json-transformer content-type="application/json"/>
</int:chain>
<int:service-activator input-channel="dentalGatewayChannel" ref="dentalGatewayWrapper" output-channel="dentalReplyChannel" />
<int:gateway id="dentalGatewayWrapper" default-request-channel="dentalCostEstimateRequestChannel" error-channel="dentalErrorChannel"/>
<int-http:outbound-gateway id="dentalGateway"
url-expression="#urlBuilder.build('${service.endpoint}')"
http-method="POST" request-factory="clientHttpRequestFactory"
request-channel="dentalCostEstimateRequestChannel" extract-request-payload="true"
expected-response-type="com.dental.test.DentalResponse">
<int-http:request-handler-advice-chain>
<ref bean="logChainTimeInterceptor" />
</int-http:request-handler-advice-chain>
</int-http:outbound-gateway>
<!-- EXCEPTION -->
<int:chain input-channel="dentalErrorChannel" output-channel="dentalAggregatorChannel">
<int:transformer ref="commonErrorTransformer" method="dentalGracefulReturn"/>
</int:chain>
<!-- SUCCESS -->
<int:chain input-channel="dentalReplyChannel" output-channel="dentalAggregatorChannel">
<int:filter discard-channel="dentalErrorChannel"
expression="T(com.dental.util.InvocationOutcomeHelper).isOutcomeSuccess(payload?.metadata?.outcome?.code,payload?.metadata?.outcome?.message)" />
</int:chain>
<!-- AGGREGATION -->
<int:chain input-channel="dentalAggregatorChannel" output-channel="wsDentalServiceOutputChannel" >
<int:aggregator ref="dentalServiceAggregator" />
<int:service-activator ref="dentalResponseServiceActivator" />
</int:chain>
What I noticed was this, every split channel when passing through the gateway creates a new temporary channel for error and reply and after getting the response back from the gateway, it retains the preserved (original inbound) error and reply channel header. And as you had mentioned, after the control gets to the error transformer that flow of retaining the preserved headers gets broken and the aggregating message group processor receives three different instances of temporary channel and hence removes them.
I was planning to have a custom message group processor and modify the conflict resolution strategy for aggregating the header and came up with this config.
<bean id="channelPreservingAggregatingMessageHandler" class="org.springframework.integration.aggregator.AggregatingMessageHandler">
<constructor-arg name="processor" ref="channelPreservingMessageGroupProcessor"/>
</bean>
I'm yet to test this out though. But based on this discussion, this does not look like a viable solution.
And looks like my configuration for error handling in gateway is incorrect.
However, I'm confused on this statement of yours "Instead of forwarding the message directly, simply handle the error on your error flow and return the result normally to the gateway "wrapper"". If I remove the error channel how will I get the control back when an exception occurs? May be I'm missing to understand something here. Can you elaborate more on this please?
When asking questions about scenarios such as this, you generally need to show your configuration. However, I suspect you are forwarding the message from the error flow directly to the aggregator.
This is like doing a GOTO in code and breaks the scoping.
It won't work because the replyChannel header in the error message is for the gateway "wrapper", not the original upstream inbound gateway. When the aggregator gets conflicting headers, it has no choice but to drop the headers (you will see a DEBUG log message to that effect).
Instead of forwarding the message directly, simply handle the error on your error flow and return the result normally to the gateway "wrapper" (simply omit the error channel on the last element on the error flow).
The gateway will then fix up the reply so it is consistent with other messages (good and bad) and forward it to the aggregator.
You don't need to mess with headers in your error flow, just return the value you want to be aggregated along with the good results.
You should really update to a current release, or at least the latest in the 2.2.x line (2.2.6).
This is how my configuration looks like
<int-file:inbound-channel-adapter id="files" directory="${lz.dir.${ft}}">
<int:poller fixed-delay="3000" max-messages-per-poll="3" />
</int-file:inbound-channel-adapter>
<int:bridge input-channel="files" output-channel="sourceFiles" />
<int:channel id="sourceFiles">
<int:dispatcher task-executor="executor" />
</int:channel>
<int:service-activator input-channel="sourceFiles"
ref="moveToSource"
method="move" />
<int:aggregator id="filesBuffered"
input-channel="sourceFiles"
output-channel="stagedFiles"
release-strategy-expression="size() == 10"
correlation-strategy-expression="'mes-group'"
expire-groups-upon-completion="true"
/>
<int:channel id="stagedFiles" />
<int:service-activator input-channel="stagedFiles"
ref="moveToStage"
method="move" />
<task:executor id="executor" pool-size="5" queue-capacity="0" rejection-policy="CALLER_RUNS" />
The idea is to poll a directory every 3 second and emit 3 messages per poll to a dispatcher based on channel to allow asynchronous execution. Messages are then aggregated based on number of messages and then emitted to next service activator. The first service activator places files in source directory and second service activator which gets the aggregated list to move those files to staging directory.
What seems to be happening is that source folder skips some files but the staging folder does gets all the files. My guess is that poller sends the messages to the dispatcher channel but when its thread pool gets full it simply ignores the files but somehow the aggregator still gets all the files. Almost like dispatcher channel skips the first service activator step for files it receives after the thread pool limit has reached but those files are still passed to next channel and thats how they still end up getting processed by the second service activator.
What I would like to do is have the poller resend the files that were rejected by the dispatcher. Any ideas would be appreciated.
Thanks
Sorry, I don't understand what you describe, but by your configuration it looks like:
sourceFiles channel is point-to-point one. So, only one subscriber at a time can get message from that channel.
But you have two subscribers - service-activator and aggregator
By default dispatcher uses RoundRobinLoadBalancingStrategy. That means, that first message will be processed by first subscriber, the second one - by second subscriberб and so on, like relay.
So, if you want to have a sequential, there is need to subscribe aggregator to the outbound-channel of moveToSource service-activator and return from move method the same payload. In your case File.
If it isn't your case, so provide, please, correct config or explain your use-case.
Now it is confused, sorry.
HTH