Conditional File movement in Spring Integration File Support

Question

I am implementing one Spring Integration work flow as below.

IntegrationFlows.from("inputFileProcessorChannel")
                           .split(fileSplitterSpec, spec -> {})
                           .transform(lineItemTransformer)
                           .handle(httpRequestExecutingMessageHandler)
                           .transform(reportDataAggregator)
                           .aggregate(aggregatorSpec -> aggregatorSpec.requiresReply(false))
                           .channel("reportGeneratorChannel")
                           .get();

Now, once the above flow is completed, I need to move the input file to a archive directory. The decision to decide on the destination directory is based on a message header processingFailed and this header is added in .transform(reportDataAggregator) step in the flow. To move this files I have create another flow as in below code

 IntegrationFlows.from(MessageChannels.direct("inputFileProcessorChannel"))
                           .routeToRecipients(routerSpec -> {
                               routerSpec.recipient("processedFileMoverChannel", createMessageSelector(Boolean.FALSE))
                                         .recipient("failedFileMoverChannel", createMessageSelector(Boolean.TRUE));
                           })

                           .get();

Selector method

 private MessageSelector createMessageSelector(Boolean ruleBoolean) {
    return message -> ruleBoolean.equals(message.getHeaders().get("processingFailed"));
}

Report Channel flow below

IntegrationFlows.from("reportGeneratorChannel")
                           .transform(executionReportTransformer)
                           .handle(reportWritingMessageHandlerSpec)
                           .get();

But, as expected with this flow, File movement is not done as the said header is not present into the flow execution.

So, How to achieve this goal to Execute the file mover flow after the report file is created?

You have two flows consuming from the `inputFileProcessorChannel` - if it is a `DirectChannel` they will get alternate messages (by default). What is consuming from `reportGeneratorChannel`? — Gary Russell, Mar 31 '20 at 20:06
Yes, thanks Gary, I see this issue with DirectChannel. Will change it. `reportGeneratorChannel` is terminal operation. No consumer after it — Vijay Shanker Dubey, Mar 31 '20 at 20:13

score 3 · Accepted Answer · answered Mar 31 '20 at 20:07

The FileSplitter populates for us this headers for each line to produce:

@Override
protected boolean willAddHeaders(Message<?> message) {
    Object payload = message.getPayload();
    return payload instanceof File || payload instanceof String;
}

@Override
protected void addHeaders(Message<?> message, Map<String, Object> headers) {
    File file = null;
    if (message.getPayload() instanceof File) {
        file = (File) message.getPayload();
    }
    else if (message.getPayload() instanceof String) {
        file = new File((String) message.getPayload());
    }
    if (file != null) {
        if (!headers.containsKey(FileHeaders.ORIGINAL_FILE)) {
            headers.put(FileHeaders.ORIGINAL_FILE, file);
        }
        if (!headers.containsKey(FileHeaders.FILENAME)) {
            headers.put(FileHeaders.FILENAME, file.getName());
        }
    }
}

So, even if you done with an aggregation and ready to send a message into that .channel("reportGeneratorChannel"), you still have access to those file-related headers.

Making this reportGeneratorChannel as a PublishSubscribeChannel and move that "file mover flow" over there, would do the trick for you.

By the way: what you have so far with a IntegrationFlows.from(MessageChannels.direct("inputFileProcessorChannel")) and a second flow on the same channel would lead you to round-robin dispatching. That's not pub-sub distribution. See more info in docs: https://docs.spring.io/spring-integration/docs/current/reference/html/core.html#channel

Making this `reportGeneratorChannel` as a `PublishSubscribeChannel` : After doing this `The Payload` passed to file mover flow will be the list from aggregator and it will try to copy this data only in the file? Is not it? — Vijay Shanker Dubey, Mar 31 '20 at 20:20
You can make a fist endpoint of that mover flow as a `transform()` to move your `File` from headers to the `payload`. — Artem Bilan, Mar 31 '20 at 20:22
Hi Artem, Can I execute the `httpRequestExecutingMessageHandler` in async mode and let every thing else, as it is? — Vijay Shanker Dubey, Apr 01 '20 at 18:39
If you place an `ExecutorChannel` just after the `split()`, you would not need to worry about an async mode for HTTP: everything is going to be performed in parallel on their own threads. For async behavior you need to take a look into a WebFlux support: https://docs.spring.io/spring-integration/docs/current/reference/html/webflux.html#webflux — Artem Bilan, Apr 01 '20 at 18:43

Conditional File movement in Spring Integration File Support

1 Answers1