karma-child-process

Framework for karma-test-runner which forks a process on startup to run a
separate node process during the karma tests. Internally it uses the fork method
of the child_process node module.

Intention

The framework is intended to run a separate node process during karma tests.
The process is supposed to mock a (http) server. This is particularly useful
for E2E-tests without the need for a complete Docker-setup. Therefore the test
setup can start faster, with less costs for infrastructure.

Installation

To install the karma-child-process framework in your local directory type
``


npm install karma-child-process --save-dev


Of course you need to install

karma

 as well.


npm install karma --save-dev


Configuration

For configuration put this into your

karma.conf.js


config = {
  frameworks: ['child-process'],
  client: {
    childProcess: {
      path: 'path/to/mock-server.js',
      args: [],
      options: {}
    }
  }
}

The

path

 is a mandatory argument providing the location of the node-script 
that should be started. The path is a relative path based on the

basePath

 
of the project. The

args and options

 arguments are optional and if provided 
directly forwarded to the

fork

 method. 
 
To execute the karma framework just run karma.


./node_modules/karma/bin/karma start

The

mock-server.js

 should be node-script that is supposed to start a server. 
A possible example might look like so:


/ eslint-env node /
const express = require('express');
const bodyParser = require('body-parser');
 
const app = express();
 
app.use(bodyParser.json());
 
let mainResponse = {};
 
app.post('/setMainResponseForTesting', (req, res) => {
  mainResponse = req.body;
  res.header('Access-Control-Allow-Origin', 'http://localhost:9876');
  res.json(req.body);
});
 
app.get('/productiveEndpoint', (req, res) => {
  res.header('Access-Control-Allow-Origin', 'http://localhost:9876');
  res.json(mainResponse);
});
 
app.get('/reset', (req, res) => {
  mainResponse = {};
  res.header('Access-Control-Allow-Origin', 'http://localhost:9876');
  res.json('Reset!');
});
 
app.listen(8000);


In this case the express-server would run on

localhost

 port 8000. But you may configure 
this via the

args

 argument provided in the karma configuration. This is very 
basic example. For real-world problems you might need a more complex setup. 
Remember that you are not limited to

express

. You may use any node-script that 
provides the desired solution for your development. 
Shutdown

During shutdown of the karma server the forked process is stopped as well. 
There is no reset of the server as long as the karma server is running, 
especially not between different runs of your test suite or even single tests. 
If you want to achieve this then use the

/reset

 Endpoint on your server and
trigger it programmatically.
License

This project is licensed under the Apache 2.0 license. For further information 
have a look into the

LICENSE` file in the project root folder.