feat: mock server helper (#4155)

Author: kobenguyent

.github/workflows/mockServerHelper.yml

@@ -0,0 +1,34 @@
+name: Mock Server Tests
+
+on:
+  push:
+    branches:
+      - 3.x
+  pull_request:
+    branches:
+      - '**'
+
+env:
+  CI: true
+  # Force terminal colors. @see https://www.npmjs.com/package/colors
+  FORCE_COLOR: 1
+
+jobs:
+  build:
+
+    runs-on: ubuntu-22.04
+
+    strategy:
+      matrix:
+        node-version: [20.x]
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v4
+      with:
+        node-version: ${{ matrix.node-version }}
+    - name: npm install
+      run: npm i --legacy-peer-deps
+    - name: run unit tests
+      run: npm run test:unit:mockServer

docs/helpers/MockServer.md

@@ -0,0 +1,212 @@
+---
+permalink: /helpers/MockServer
+editLink: false
+sidebar: auto
+title: MockServer
+---
+
+<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
+
+## MockServer
+
+MockServer
+
+The MockServer Helper in CodeceptJS empowers you to mock any server or service via HTTP or HTTPS, making it an excellent tool for simulating REST endpoints and other HTTP-based APIs.
+
+
+
+## Configuration
+
+This helper should be configured in codecept.conf.(js|ts)
+
+Type: [object][1]
+
+### Properties
+
+-   `port` **[number][2]?** Mock server port
+-   `host` **[string][3]?** Mock server host
+-   `httpsOpts` **[object][1]?** key & cert values are the paths to .key and .crt files
+
+
+
+#### Examples
+
+You can seamlessly integrate MockServer with other helpers like REST or Playwright. Here's a configuration example inside the `codecept.conf.js` file:
+
+```javascript
+{
+  helpers: {
+    REST: {...},
+    MockServer: {
+      // default mock server config
+      port: 9393,
+      host: '0.0.0.0',
+      httpsOpts: {
+        key: '',
+        cert: '',
+      },
+    },
+  }
+}
+```
+
+#### Adding Interactions
+
+Interactions add behavior to the mock server. Use the `I.addInteractionToMockServer()` method to include interactions. It takes an interaction object as an argument, containing request and response details.
+
+```javascript
+I.addInteractionToMockServer({
+   request: {
+     method: 'GET',
+     path: '/api/hello'
+   },
+   response: {
+     status: 200,
+     body: {
+       'say': 'hello to mock server'
+     }
+   }
+});
+```
+
+#### Request Matching
+
+When a real request is sent to the mock server, it matches the received request with the interactions. If a match is found, it returns the specified response; otherwise, a 404 status code is returned.
+
+-   Strong match on HTTP Method, Path, Query Params & JSON body.
+-   Loose match on Headers.
+
+##### Strong Match on Query Params
+
+You can send different responses based on query parameters:
+
+```javascript
+I.addInteractionToMockServer({
+  request: {
+    method: 'GET',
+    path: '/api/users',
+    queryParams: {
+      id: 1
+    }
+  },
+  response: {
+    status: 200,
+    body: 'user 1'
+  }
+});
+
+I.addInteractionToMockServer({
+  request: {
+    method: 'GET',
+    path: '/api/users',
+    queryParams: {
+      id: 2
+    }
+  },
+  response: {
+    status: 200,
+    body: 'user 2'
+  }
+});
+```
+
+-   GET to `/api/users?id=1` will return 'user 1'.
+-   GET to `/api/users?id=2` will return 'user 2'.
+-   For all other requests, it returns a 404 status code.
+
+##### Loose Match on Body
+
+When `strict` is set to false, it performs a loose match on query params and response body:
+
+```javascript
+I.addInteractionToMockServer({
+  strict: false,
+  request: {
+    method: 'POST',
+    path: '/api/users',
+    body: {
+      name: 'john'
+    }
+  },
+  response: {
+    status: 200
+  }
+});
+```
+
+-   POST to `/api/users` with the body containing `name` as 'john' will return a 200 status code.
+-   POST to `/api/users` without the `name` property in the body will return a 404 status code.
+
+Happy testing with MockServer in CodeceptJS! 🚀
+
+## Methods
+
+### Parameters
+
+-   `passedConfig`  
+
+### addInteractionToMockServer
+
+An interaction adds behavior to the mock server
+
+```js
+I.addInteractionToMockServer({
+   request: {
+     method: 'GET',
+     path: '/api/hello'
+   },
+   response: {
+     status: 200,
+     body: {
+       'say': 'hello to mock server'
+     }
+   }
+});
+```
+
+```js
+// with query params
+I.addInteractionToMockServer({
+   request: {
+     method: 'GET',
+     path: '/api/hello',
+     queryParams: {
+      id: 2
+    }
+   },
+   response: {
+     status: 200,
+     body: {
+       'say': 'hello to mock server'
+     }
+   }
+});
+```
+
+#### Parameters
+
+-   `interaction` **(CodeceptJS.MockInteraction | [object][1])** add behavior to the mock server
+
+Returns **any** void
+
+### startMockServer
+
+Start the mock server
+
+#### Parameters
+
+-   `port` **[number][2]?** start the mock server with given port
+
+Returns **any** void
+
+### stopMockServer
+
+Stop the mock server
+
+Returns **any** void
+
+[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String