Creating a global transaction Id that is accessible through multiple packages

Question

Hi to all Java experts!

I am working on onboarding a new and shiny process visualization service and I need your help!

My project structure goes like this:

Service Package is dependant on Core Package which is dependant on Util package. Something like this:

Service
|-|- Core
|-|-|- Util

The application package has the main method from where our code begins. It's calling some of the Core methods that is using the Util package for read information from the input.

package com.dummy.service;

public void main(Object input) {
     serviceCore.call(input);
}

package com.dummy.core;

public void call(Object input) {
     String stringInput = util.readFromInput(input);
     //Do stuff
}

package com.dummy.util;

public String readFromInput(Object input) {
     //return stuff;
}

The problem starts when I want to onboard to the visualization service. One requirement is to use a unique transaction Id for each call to the service.

My question is - how to share the process Id between all of these methods without doing too much refactoring to the code? To see the entire process in the Process Visualization tool I will have to use the same ID across the entire call. My vision that this is going to be something like:

package com.dummy.service;

public void main(Object input) {
     processVisualization.signal(PROCESS_ID, "transaction started");
     serviceCore.call(input);
     processVisualization.signal(PROCESS_ID, "transaction ended");
}

package com.dummy.core;

public void call(Object input) {
     processVisualization.signal(PROCESS_ID, "Method call is invoked");
     String stringInput = util.readFromInput(input);
     //Do stuff
}

package com.dummy.util;

public String readFromInput(Object input) {
     processVisualization.signal(PROCESS_ID, "Reading from input");
     //return stuff;
}

I was thinking about the following, but all of these are just abstract ideas that I am not even sure can be implemented. And if yes - then how?

Creating a new package that all of the three packages are going to be dependant on and going to "hold" the process Id for each call. But how? Should I use a static class in this package? A singelton?
I've read this post about ThreadLocal variables: When and how should I use a ThreadLocal variable? but I am not familiar with these and not sure how to implement this idea - should it go to a separate package like I mentioned in 1?
Changing the method's signatures to pass the id as a variable. This is, unfortunately, too pricey in terms of time and the danger of a large refactoring.
Using file writing - save the ID in some file that is accessible throughout the process.
Constructing a unique id from the input - I think this can be the perfect solution but we may receive the same input in separate calls to the service.
Access the JVM for some unique transaction id. I know that when we are logging stuff we have the RequestId printed in the log line. This is the pattern we use in Log4J configuration: <pattern>%d{dd MMM yyyy HH:mm:ss,SSS} %highlight{[%p]} %X{RequestId} (%t) %c: %m%n</pattern> This RequestId is a variable on the ThreadContext that is created before the job. Is this possible and/or recommended to access this parameter and use it as a unique transaction id?

score 0 · Accepted Answer · answered Jan 21 '19 at 21:13

In the end we've utilized Log4J's Thread context. It's probably not the best solution since we are mixing the purpose of the same thing, but this is how we did it:

The process id is extracted like that: org.apache.logging.log4j.ThreadContext.get("RequestId");

And initiated on the Handler Chain (depends on which service you are using): ThreadContext.put("RequestId", Objects.toString(job.getId(), (String)null));
This is happening on every job that is received.

Disclaimer: This solution haven't been fully tested yet but this is the direction we go with

Creating a global transaction Id that is accessible through multiple packages

1 Answers1