Mocha test cases for Apigee Javascript policy.

Google Cloud Apigee
1

I am trying to write a Mocha test case. Have installed Chai & Sinon.
However when i try to run the test i get this error

Exception during run: TypeError: context.setVariable is not a function

My source js file is JS-GenerateUID.js

var transactionId = "";
var traceId = "";
transactionId = generateUUID();

function generateUUID() {
    var d = new Date().getTime();

    var uuid = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
        var r = (d + Math.random() * 16) % 16 | 0;
        d = Math.floor(d / 16);
        return (c == 'x' ? r : (r & 0x7 | 0x8)).toString(16);
    });

    context.setVariable("traceId", uuid);
    context.setVariable("transactionId", uuid);
    return uuid;
}

export { generateUUID };

And my Mocha test case is Generate-UUID.test.js

import { assert } from 'chai';
import {generateUUID} from "../apiproxy/resources/jsc/JS-GenerateUID.js";

describe('generateUUID', () => {
    it('should return a string with a valid UUID format', () => {
        const uuid = generateUUID();
        assert.match(uuid, /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i);
    });

    it('should set traceId and transactionId variables with the generated UUID', () => {
        // Mock context object
        const context = {
            setVariable(key, value) {
                this[key] = value;
            }
        };

        // Override context object for the test
        global.context = context;

        const uuid = generateUUID();

        assert.strictEqual(context.traceId, uuid);
        assert.strictEqual(context.transactionId, uuid);
    });

    // Add more test cases as needed
});

Whats wrong with the code? My guess is the context variable of apigee probably needs to be mocked or something.
But dont know, any answers would be helpful.

Thanks & Best regards,
Amitt Nerrkar

4 Likes
2

The func generateUUID it does not hace the context injected, you have to options to do so:

Option 1: Pass the context object as an argument (easiest)

Modify the generateUUID function to accept a context object as an argument:

function generateUUID(context) {
// ... existing code ...

context.setVariable("traceId", uuid);
context.setVariable("transactionId", uuid);
return uuid;
}

In your test, pass the mocked context object to the generateUUID function:

it('should set traceId and transactionId variables with the generated UUID', () => {
    const context = {
        setVariable(key, value) {
            this[key] = value;
        }
    };

    const uuid = generateUUID(context); // Pass the mocked context

    assert.strictEqual(context.traceId, uuid);
    assert.strictEqual(context.transactionId, uuid);
});

Option 2: Use Sinon to spy on the context object (if available)

If you’re using Sinon for mocking, you can leverage it to spy on the global context object and verify its interactions.

Import Sinon in your test file:

const sinon = require('sinon');

Create a spy on the setVariable method of the global context object:

it('should set traceId and transactionId variables with the generated UUID', () => {
const context = {
setVariable: sinon.spy()
};
global.context = context;

const uuid = generateUUID();

sinon.assert.calledWith(context.setVariable, "traceId", uuid);
sinon.assert.calledWith(context.setVariable, "transactionId", uuid);
});

This approach verifies that the setVariable method was called with the expected arguments instead of modifying the original functionality.

Hope this helps!

3 Likes
3

Hi @razvanbulzan - Thanks for the reply.
However i am still getting the same error message any which way i implement it.
By the way i am using this cmd “Mocha test” to run the tests.
Any leads would be useful.
Thanks & Best regards,
Amitt Nerrkar

3 Likes
4

Then maybe you’re using

context.setVariable

Somewhere else in your proxy definition, as a function,

Most likely

    context.setVariable("traceId", uuid);
    context.setVariable("transactionId", uuid);

Try removing them, or adding print statements in order to see if they executed and debug, or replace that for a print and see if it executes, hope this helps!

3 Likes