topic Re: How to pass parameters into a custom JMS Modular Input Message Handler in All Apps and Add-ons

How to pass parameters into a custom JMS Modular Input Message Handler

mcormier_splunk — Thu, 14 Jan 2016 14:29:20 GMT

I'm working on a project to convert binary JMS message bodies to Strings. I've built the converter and will integrate it using the template you've laid out in Splunk Answers
https://answers.splunk.com/answers/310006/how-to-convert-byte-characters-coming-out-of-mq-th.html

I've run into a problem. The converter uses a properties file to describe the message format. How can I get the file path/name passed into this class so I can load the message format? I see the setParams (Map<String, String> params) method, but don't know
(a) if that's the right call and
(b) how to initialize a parameter that might get passed into this call in the first place.

Anyone have an example of how they've done this, how it might be done, or a pointer to documentation?

Re: How to pass parameters into a custom JMS Modular Input Message Handler

Damien_Dallimor — Thu, 14 Jan 2016 15:08:09 GMT

Config example :

Rough code example :

package com.splunk.modinput.jms.custom.handler;

import java.io.File;
import java.util.Map;

import javax.jms.Message;

import com.splunk.modinput.jms.AbstractMessageHandler;
import com.splunk.modinput.jms.JMSModularInput.MessageReceiver;

public class ExampleMessageHandler extends AbstractMessageHandler {

    private final static String MSG_FORMAT_FILE_PARAM = "msg_format_file";

    private File msgFormatFile;

    @Override
    public void handleMessage(Message message, MessageReceiver context) throws Exception {


        String event = decodeMessageBody(message);

        transportMessage(event, String.valueOf(System.currentTimeMillis()), "");

    }

    private String decodeMessageBody(Message message) {
        String result = "";
        try {

           //TODO your logic to pull out the message bytes and decode them

        } catch (Exception e) {}

        return result;

    }

    @Override
    public void setParams(Map<String, String> params) {

        if (params.containsKey(MSG_FORMAT_FILE_PARAM))
            this.msgFormatFile = new File(params.get(MSG_FORMAT_FILE_PARAM));

    }

}

Re: How to pass parameters into a custom JMS Modular Input Message Handler

mcormier_splunk — Thu, 14 Jan 2016 15:14:29 GMT

Thanks for this! I was hoping it would be straightforward to use setParams(), just didn't know the "config" side of the equation. I will test it out and report back.