io.continual.services.processor.engine.model

Interface MessageProcessingContext

All Known Implementing Classes:

SimpleMessageProcessingContext

public interface MessageProcessingContext

A message processing context is provided to processors for access to the current message, its containing stream, and control state.

Method Summary

Modifier and Type	Method and Description
default String	evalExpression(String expression) Evaluate a ${} expression in the message context, which includes the message as primary source, then the stream processing context.
<T> T	evalExpression(String expression, Class<T> targetType, io.continual.util.data.exprEval.ExprDataSource... addlSrcs) Evaluate a ${} expression in the message context, which includes the addl srcs, the message, then the stream processing context, in that order.
default String	evalExpression(String expression, io.continual.util.data.exprEval.ExprDataSource... addlSrcs) Evaluate a ${} expression in the message context, which includes the addl srcs, the message, then the stream processing context, in that order.
String	getId() Get a unique serial number for the current message
Message	getMessage() Get the message being processed
MetricsCatalog	getMetrics() Get a metrics catalog appropriate for the scope of this message's processing
Sink	getSink(String sinkName) Get a named sink from the program
Source	getSource(String srcName) Get a named source from the program
StreamProcessingContext	getStreamProcessingContext() Get the stream processing context associated with the current message.
boolean	shouldContinue() Should the engine continue to process this message?
void	stopProcessing() Ask the engine to stop processing this message
default void	stopProcessing(String warningText) Ask the engine to stop processing this message and log the warning.
void	warn(String warningText) report a warning about processing

Method Detail

getStreamProcessingContext

StreamProcessingContext getStreamProcessingContext()

Get the stream processing context associated with the current message.

Returns:

a stream processing context

getId

String getId()

Get a unique serial number for the current message

Returns:

a serial number

getMessage

Message getMessage()

Get the message being processed

Returns:

the message

shouldContinue

boolean shouldContinue()

Should the engine continue to process this message?

Returns:

normally true, false if stopProcessing or stream context's fail has been called

stopProcessing

void stopProcessing()

Ask the engine to stop processing this message

stopProcessing

default void stopProcessing(String warningText)

Ask the engine to stop processing this message and log the warning.

Parameters:

warningText -

warn

void warn(String warningText)

report a warning about processing

Parameters:

warningText -

getSource

Source getSource(String srcName)

Get a named source from the program

Parameters:

srcName - the name of a source

Returns:

a source, or null if none by that name

getSink

Sink getSink(String sinkName)

Get a named sink from the program

Parameters:

sinkName -

Returns:

a sink, or null if none by that name

evalExpression

default String evalExpression(String expression)

Evaluate a ${} expression in the message context, which includes the message as primary source, then the stream processing context.

Parameters:

expression -

Returns:

a value, which may be an empty string

evalExpression

default String evalExpression(String expression,
                              io.continual.util.data.exprEval.ExprDataSource... addlSrcs)

Evaluate a ${} expression in the message context, which includes the addl srcs, the message, then the stream processing context, in that order.

Parameters:

expression -

Returns:

a value, which may be an empty string

evalExpression

<T> T evalExpression(String expression,
                     Class<T> targetType,
                     io.continual.util.data.exprEval.ExprDataSource... addlSrcs)

Evaluate a ${} expression in the message context, which includes the addl srcs, the message, then the stream processing context, in that order.

Parameters:

expression -

Returns:

a value, which may be an empty string

getMetrics

MetricsCatalog getMetrics()

Get a metrics catalog appropriate for the scope of this message's processing

Returns: