io.mats3.api.intercept

Interface MatsStageInterceptor

All Known Subinterfaces:

MatsStageInterceptor.MatsStageInterceptOutgoingMessages

All Known Implementing Classes:

LocalStatsMatsInterceptor, MatsMetricsLoggingInterceptor, MatsMicrometerInterceptor

public interface MatsStageInterceptor

Implement this interface to intercept Stage Processing, then register with MatsInterceptable.addStageInterceptor(MatsStageInterceptor).

Intercepts stage processors with ability to modify the stage processing, and implement extra logging and metrics gathering.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	MatsStageInterceptor.MatsStageInterceptOutgoingMessages While still within the stage process context, this interception enables modifying outgoing messages from the user lambda, setting trace properties, adding "sideloads", deleting a message, or initiating additional messages.
static interface	MatsStageInterceptor.MatsStageInterceptUserLambda Enables the intercepting of the invocation of the "user lambda" in a Stage, with ability to wrap the MatsEndpoint.ProcessContext (and thus modify any reply, request, next or initiations) and/or modifying state and message - or even take over the entire stage.
static interface	MatsStageInterceptor.StageCommonContext Common context elements for stage interception, including all the incoming message/envelope data and metadata.
static interface	MatsStageInterceptor.StageCompletedContext
static interface	MatsStageInterceptor.StageInterceptContext
static interface	MatsStageInterceptor.StageInterceptOutgoingMessageContext
static interface	MatsStageInterceptor.StageInterceptUserLambdaContext
static interface	MatsStageInterceptor.StagePreprocessAndDeserializeErrorContext
static interface	MatsStageInterceptor.StageReceivedContext

Method Summary

Modifier and Type	Method and Description
default void	stageCompleted(MatsStageInterceptor.StageCompletedContext context) Invoked after the stage is fully completed, outgoing messages sent, db and messaging system committed.
default void	stageCompletedNextDirect(MatsStageInterceptor.StageCompletedContext context) Special variant of stageCompleted(StageCompletedContext) which is invoked when a MatsEndpoint.ProcessContext.nextDirect(Object) has been performed: As opposed to the ordinary variant, this does not execute outside the stage's transactional demarcation, since the nextDirect stage processing happens within the same transactional demarcation as the stage which invoked nextDirect.
default void	stagePreprocessAndDeserializeError(MatsStageInterceptor.StagePreprocessAndDeserializeErrorContext context) Invoked if any of the preprocessing and deserialization activities on the incoming message from the message system fails, and hence no Stage processing will be performed - i.e., no further methods of the interceptor will be invoked.
default void	stageReceived(MatsStageInterceptor.StageReceivedContext context) Invoked right after message have been received, preprocessed and deserialized, before invoking the user lambda.

Method Detail

stagePreprocessAndDeserializeError

default void stagePreprocessAndDeserializeError(MatsStageInterceptor.StagePreprocessAndDeserializeErrorContext context)

Invoked if any of the preprocessing and deserialization activities on the incoming message from the message system fails, and hence no Stage processing will be performed - i.e., no further methods of the interceptor will be invoked. Conversely, this method will not be invoked in normal situations: If the normal user lambda throws, or database or messaging system fails, this will result in the MatsStageInterceptor.StageCompletedContext of the stageCompleted(..) call describe the problem and contain the cause, see MatsStageInterceptor.StageCompletedContext.ProcessResult.USER_EXCEPTION and MatsStageInterceptor.StageCompletedContext.ProcessResult.SYSTEM_EXCEPTION.

Note: This should really never be triggered. It would be prudent to "notify the humans" if it ever did.

stageReceived

default void stageReceived(MatsStageInterceptor.StageReceivedContext context)

Invoked right after message have been received, preprocessed and deserialized, before invoking the user lambda. (If any error occurs during preprocess or deserialization, then stagePreprocessAndDeserializeError(StagePreprocessAndDeserializeErrorContext) is invoked instead).

stageCompleted

default void stageCompleted(MatsStageInterceptor.StageCompletedContext context)

Invoked after the stage is fully completed, outgoing messages sent, db and messaging system committed. You cannot anymore modify any outgoing messages etc - for this, implement MatsStageInterceptor.MatsStageInterceptOutgoingMessages.

See Also:

stageCompletedNextDirect(StageCompletedContext)

stageCompletedNextDirect

default void stageCompletedNextDirect(MatsStageInterceptor.StageCompletedContext context)

Special variant of stageCompleted(StageCompletedContext) which is invoked when a MatsEndpoint.ProcessContext.nextDirect(Object) has been performed: As opposed to the ordinary variant, this does not execute outside the stage's transactional demarcation, since the nextDirect stage processing happens within the same transactional demarcation as the stage which invoked nextDirect. Therefore, no outgoing messages has yet been sent, and db and message system are not yet committed.