grunt-galvanize

Run other grunt tasks multiple times with different options.

Install

$ npm install --save-dev grunt-galvanize

Why?

Using grunt with static configurations has its limits. Perhaps your build process needs to read in a list of files from disk, then perform tasks on those files. This is made difficult by the fact that grunt.task.run simply queues a new task to be run. Thus the state of grunt.config may change between the time that the task was queued and when it is run. Galvanize allows you to define critical components of grunt.options and grunt.config, and ensure that those components are in the desired state when a sub-task is run. In practice, this enables calling grunt.task.run within a loop.

Usage

Create galvanizeConfig:

The galvanizeConfig is an array of objects with a configs and an options property. The configs and options will be used to set grunt config and grunt options before running each iteration of a task.

   grunt.option('galvanizeConfig', [
       { configs: {color: 'red'}, options: {size: small} },
       { configs: {color: 'green'}, options: {size: small}
   ]);

Run galvanize:

Run the galvanize task, specifying the task that you would like galvanize to iterate.

grunt.task.run(['galvanize:myTask']);

The above config will result in running myTask once with grunt.config.color = 'red', and once with grunt.config.color = 'green'.

Get fancy

For nested configs and options, use an array to specify the key and value:

    grunt.option('galvanizeConfig', [
        {
            configs: [
                { key: ['browserify', 'files'], value: '/mnt/foo/bar/**.js' },
                { key: ['browserify', 'dedup'], value: false }
            ]
        },
        {
            configs: [
                { key: ['browserify', 'files'], value: '/mnt/foo/baz/**.js' },
                { key: ['browserify', 'dedup'], value: true }
            ]
        }
    ]);

    grunt.task.run(['galvanize:browserify']);

The above config will run browserify once with grunt.config.browserify.files set to /mnt/foo/bar/**.js, and once with grunt.config.browserify.files set to /mnt/foo/baz/**.js.

The galvanizeConfig can be easily created programmatically within your build process.

In the wild:

Here's a snippet from our code base that takes advantage of Galvanize

/**
 * Run udb on each changelog in the master runlist
 * @param {string} db is the alias for the DB against which changelogs should be run.
 *   defaults to the db defined for the current branch in config.dbBranchMap.
 */
grunt.registerTask('execRunlist', '', function(db) {
    var runlistPath = config.get('masterRunlist');
    var runlist = grunt.file.readJSON(runlistPath);

    // verify that runlist is an array
    if (!_.isArray(runlist)) {
        throw new Error(
            'runlist is not an array: it is a ' + typeof runlist
        );
    }

    // map runlists to options object
    var galvanizeConfig = runlist.map(function(path) {
        return {options: {path: path}};
    });

    grunt.option('galvanizeConfig', galvanizeConfig);
    grunt.task.run([
        'galvanize:udb', //run udb for each path in galvanizeConfig
        'galvanize:dequeueFromRunlist' //remove each path in galvanizeConfig from runlist
    ]);
});

Contributing

Please submit any changes to this repo (including additions and subtractions from the lint config files) as pull requests.