REST helper config: `onResponse` provided in config does not work

[apatelia]

I am using default REST helper for API testing, and I want to measure and assert the API's response time. For that I am trying following.

In my codecept.conf.ts:

 helpers: {
 REST: {
 endpoint: 'https://myServerUrl',

 onRequest: (request) => {
 console.log('onRequest');
 request.headers[ 'start-time' ] = new Date().getTime();
 },

 onResponse: (response) => {
 console.log('onResponse');
 const startTime = response.request.headers[ 'start-time' ];
 const endTime = new Date().getTime();
 const responseTime = endTime - startTime;
 response. Headers[ 'x-response-time' ] = responseTime;
 },
 },

 JSONResponse: {}
 }

and then in my custom helper:

 const response = this.helpers.JSONResponse.response;
 
 console.log(`Response time: ${response.headers[ 'x-response-time' ]} ms`);

I can see that onRequest from REST config works as expected but onResponse does not work.

My output:

onRequest
Response time: undefined ms

[myrepojuly]

@kobenguyent @DavertMik - The issue is with the onResponse Handler Overridden in lib/helper/JSONResponse.js file

The problem lies in the lib/helper/JSONResponse.js file, specifically in the _beforeSuite() method.

Currently, the following code unconditionally overrides any existing onResponse handler set in the request helper config:

_beforeSuite() {
 this.response = null
 if (!this.helpers[this.options.requestHelper]) {
 throw new Error(`Error setting JSONResponse, helper ${this.options.requestHelper} is not enabled in config, helpers: ${Object.keys(this.helpers)}`)
 }
 // connect to REST helper
 this.helpers[this.options.requestHelper].config.onResponse = response => {
 this.response = response
 }
 }

Problem:
This implementation overrides any custom onResponse handler that may have already been set in the user's configuration, causing their logic to be lost.

Suggested Fix:
Preserve the original onResponse handler by wrapping it, rather than replacing it:

const originalOnResponse = this.helpers[this.options.requestHelper].config.onResponse
this.helpers[this.options.requestHelper].config.onResponse = response => {
 if (originalOnResponse) originalOnResponse(response)
 this.response = response
}

This ensures that both the user-defined handler and the JSONResponse logic are executed.