Having WSO2 5.0.0 trying to implement the store and forward pattern with a JDBC message store.
Sending a message to the target endpoint throws an exception:
TID: [-1234] [] [2016-12-05 23:25:24,874] ERROR {org.apache.synapse.message.processor.impl.sampler.SamplingService} - Error occurred while executing the message {org.apache.synapse.message.processor.impl.sampler.SamplingService}
org.apache.synapse.SynapseException: Unexpected error during sending message out
at org.apache.synapse.core.axis2.Axis2Sender.handleException(Axis2Sender.java:257)
at org.apache.synapse.core.axis2.Axis2Sender.sendOn(Axis2Sender.java:84)
at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.send(Axis2SynapseEnvironment.java:548)
at org.apache.synapse.endpoints.AbstractEndpoint.send(AbstractEndpoint.java:382)
at org.apache.synapse.endpoints.AddressEndpoint.send(AddressEndpoint.java:65)
at org.apache.synapse.endpoints.IndirectEndpoint.send(IndirectEndpoint.java:55)
at org.apache.synapse.mediators.builtin.CallMediator.handleNonBlockingCall(CallMediator.java:221)
at org.apache.synapse.mediators.builtin.CallMediator.mediate(CallMediator.java:99)
at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:97)
at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:59)
at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:158)
at org.apache.synapse.message.processor.impl.sampler.SamplingService$1.run(SamplingService.java:211)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
at org.apache.synapse.core.axis2.Axis2FlexibleMEPClient.send(Axis2FlexibleMEPClient.java:538)
at org.apache.synapse.core.axis2.Axis2Sender.sendOn(Axis2Sender.java:78)
... 15 more
I believe I am missing an important transport, Axis2 or Synapse property, but I am unable to find which one.
Sequences to store and forward are here.
I was trying to find out in the source codes what could be causing the NullPointerException, but for me it makes no sense as the httpMethod and messageType is defined.
Thank you all for any hint
Edit: based on a comment, the Synapse source in use is here.