How to Write Global Functions in Postman

Question

I need help writing a common function to use across a collection of requests which will help with building a framework.

I have tried using the below format

Answer 1

You can have a more readable solution and more possibility to factor your code (like calling function1() from function2() directly inside your pre-request script, or declaring packages) with the following syntax :

Initialize environment (or globals) :

postman.setEnvironmentVariable("utils", () => {
    var myFunction1 = () => {
        //do something
    }
    var myFunction2 = () => {
        let func1Result = myFunction1();
        //do something else
    }
    return {
        myPackage: {
            myFunction1,
            myFunction2
        }
    };
});

And then use your functions in a later test :

let utils = eval(environment.utils)();
utils.myPackage.myFunction1(); //calls myFunction1()
utils.myPackage.myFunction2(); //calls myFunction2() which uses myFunction1()

Bonus :

If you are calling an API and need to wait the call to finish before performing a test, you can do something like this:

postman.setEnvironmentVariable("utils", () => {
    var myFunction = (callback) => {
        return pm.sendRequest({
            // call your API with postman here
        }, function (err, res) {
            if (callback) {
                //if a callback method has been given, it's called
                callback();
            }
        });
    }

    return {
        myPackage: {
            myFunction,
        }
    };
});

and then to use it:

utils.myPackage.myFunction(function() {
    console.log("this is the callback !")
    //perform test here
});