grunt-karma

Grunt plugin for Karma

This current version uses [email protected]. For using older versions see the old releases of grunt-karma.

Getting Started

From the same directory as your project's Gruntfile and package.json, install karma and grunt-karma with the following commands:

$ npm install karma --save-dev
$ npm install grunt-karma --save-dev

Once that's done, add this line to your project's Gruntfile:

grunt.loadNpmTasks('grunt-karma');

Config

Inside your Gruntfile.js file, add a section named karma, containing any number of configurations for running karma. You can either put your config in a [karma config file] or leave it all in your Gruntfile (recommended).

Here's an example that points to the config file:

karma: {
  unit: {
    configFile: 'karma.conf.js'
  }
}

Here's an example that puts the config in the Gruntfile:

karma: {
  unit: {
    options: {
      files: ['test/**/*.js']
    }
  }
}

You can override any of the config file's settings by putting them directly in the Gruntfile:

karma: {
  unit: {
    configFile: 'karma.conf.js',
    port: 9999,
    singleRun: true,
    browsers: ['PhantomJS'],
    logLevel: 'ERROR'
  }
}

To change the logLevel in the grunt config file instead of the karma config, use one of the following strings: OFF, ERROR, WARN, INFO, DEBUG

The files option can be extended "per-target" in the typical way Grunt handles files:

karma: {
  options: {
    files: ['lib/**/*.js']
  },
  unit: {
    files: [
      { src: ['test/**/*.js'] }
    ]
  }
}

When using the "Grunt way" of specifying files, you can also extend the file objects with the options supported by karma:

karma: {
  unit: {
    files: [
      { src: ['test/**/*.js'], served: true },
      { src: ['lib/**/*.js'], served: true, included: false }
    ]
  }
}

Config with Grunt Template Strings in files

When using template strings in the files option, the results will flattened. Therefore, if you include a variable that includes an array, the array will be flattened before being passed to Karma.

Example:

meta: {
  jsFiles: ['jquery.js','angular.js']
},
karma: {
  options: {
    files: ['<%= meta.jsFiles %>','angular-mocks.js','**/*-spec.js']
  }
}

Sharing Configs

If you have multiple targets, it may be helpful to share common configuration settings between them. Grunt-karma supports this by using the options property:

karma: {
  options: {
    configFile: 'karma.conf.js',
    port: 9999,
    browsers: ['Chrome', 'Firefox']
  },
  continuous: {
    singleRun: true,
    browsers: ['PhantomJS']
  },
  dev: {
    reporters: 'dots'
  }
}

In this example the continuous and dev targets will both use the configFile and port specified in the options. But the continuous target will override the browser setting to use PhantomJS, and also run as a singleRun. The dev target will simply change the reporter to dots.

Running tests

There are three ways to run your tests with karma:

Karma Server with Auto Runs on File Change

Setting the autoWatch option to true will instruct karma to start a server and watch for changes to files, running tests automatically:

karma: {
  unit: {
    configFile: 'karma.conf.js',
    autoWatch: true
  }
}

Now run $ grunt karma

Karma Server with Grunt Watch

Many Grunt projects watch several types of files using grunt-contrib-watch. Config karma like usual (without the autoWatch option), and add background:true:

karma: {
  unit: {
    configFile: 'karma.conf.js',
    background: true,
    singleRun: false
  }
}

The background option will tell grunt to run karma in a child process so it doesn't block subsequent grunt tasks.

The singleRun: false option will tell grunt to keep the karma server up after a test run.

Config your watch task to run the karma task with the :run flag. For example:

watch: {
  //run unit tests with karma (server needs to be already running)
  karma: {
    files: ['app/js/**/*.js', 'test/browser/**/*.js'],
    tasks: ['karma:unit:run'] //NOTE the :run flag
  }
},

In your terminal window run $ grunt karma:unit:start watch, which starts the karma server and the watch task. Now when grunt watch detects a change to one of your watched files, it will run the tests specified in the unit target using the already running karma server. This is the preferred method for development.

Single Run

Keeping a browser window & karma server running during development is productive, but not a good solution for build processes. For that reason karma provides a "continuous integration" mode, which will launch the specified browser(s), run the tests, and close the browser(s). It also supports running tests in PhantomJS, a headless webkit browser which is great for running tests as part of a build. To run tests in continous integration mode just add the singleRun option:

karma: {
  unit: {
    configFile: 'config/karma.conf.js',
  },
  //continuous integration mode: run tests once in PhantomJS browser.
  continuous: {
    configFile: 'config/karma.conf.js',
    singleRun: true,
    browsers: ['PhantomJS']
  },
}

The build would then run grunt karma:continuous to start PhantomJS, run tests, and close PhantomJS.

Using additional client.args

You can pass arbitrary client.args through the commandline like this:

$ grunt karma:dev watch --grep=mypattern

Karma Server in a background process

karma: {
  unit: {
    background: true,
    onBackgroundStart: function(data) {
      // data.pid returned -- background process id
      // Called with karma background process starts
    },
    backgroundServerEvents: ['run_complete', 'browser_error'], // <--- listen to karma server events
    onBackgroundMessage: function(response) {
      // Karma server events returned
      // See http://karma-runner.github.io/1.0/dev/public-api.html
      if (response.event === 'run_complete') {
         console.log(response.pid);         // <--- background process id
         console.log(response.data[0]);     // <--- 'browsers' data from 'run_complete' event
         console.log(response.data[1]);     // <--- 'results' data from 'run_complete' event
      }
    }
  }
}

The background option will tell grunt to run karma in a child process so it doesn't block subsequent grunt tasks.

The onBackgroundStart option is a callback function called when the child process is created. It only returns the background process id.

The backgroundServerEvents option is an array of karma server events to have returned to the parent process via the onBackgroundMessage callback. Examples include ['browser_register', 'browser_error', 'run_complete']. See the Karma public api for a full list of events.

The onBackgroundMessage option is a callback function called that receives karma server events passed in the 'backgroundServerEvents' array. The response object has the following properties:

 {
   pid: 1234,                   // <--- background process id
   event: 'run_complete',       // <--- event name 
   data: [browsers, results]    // <--- Array of arguments returned from event
 }

License

MIT License