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springspring-bootspring-integration

Spring integration rotating server advice with SFTP outbound gateway

I wanted to ask if I could use a rotating server advice with SFTP outbound Gateway, I am polling files with SFTP inbound adapter, and in the poller method I'm using rotating server advice. It works flawlessly, but I want to rename the files when I'm done with the flow.

I'm using SFTP outbound gateway, it does not need a poll. I just want to rename whenever I get a message in my output channel. How can I use advice or make sure that the right file is renamed on the right server, I have multiple servers and multiple directories?

Also, similar question for a different solution, is there a way to just list files on my multiple servers and directories. I don't want to download or get a stream to the file I just want to get the file name and path. For this as well, I'm using SFTP outbound gateway with list command but it seems that it does not rotate on my multiple servers/directories either.

Solution

  • No, you cannot use a RotatingServerAdvice on the outbound gateway: it is fully tied to the MessageSource logic in something like that SFTP inbound adapter. However you still can use a DelegatingSessionFactory on the SFTP outbound gateway together with a ContextHolderRequestHandlerAdvice to set a thread local key for the target session factory. Then SftpRemoteFileTemplate is going to select a proper target session factory for the specific gateway operation.

    You can have a splitter for those keys to iterate before your SFTP outbound gateway to list dir on the specific server. Then you can have an aggregator to collect those results into a single message.

    The SFTP inbound adapter provides some specific info into the message it emits:

            String remoteFileUri = this.synchronizer.getRemoteFileMetadata(messageBuilder.getPayload());
        if (remoteFileUri != null) {
            URI uri = URI.create(remoteFileUri);
            messageBuilder.setHeader(FileHeaders.REMOTE_HOST_PORT, uri.getHost() + ':' + uri.getPort())
                    .setHeader(FileHeaders.REMOTE_DIRECTORY, uri.getPath())
                    .setHeader(FileHeaders.REMOTE_FILE, uri.getFragment());
        }

    So, you may use that FileHeaders.REMOTE_HOST_PORT to determine the target server for file renaming in the end of your flow.

    See more info in docs:

    https://docs.spring.io/spring-integration/reference/sftp/remote-file-info.html

    https://docs.spring.io/spring-integration/reference/handler-advice/context-holder.html