Title: Intro to Jake - JavaScript build tool for Node.js Author: Matthew Eernisse Date: Wed Sep 29 2010 12:39:01 GMT+0530 (IST)
Jake is a JavaScript build program for Node.js, with capabilities similar to GNU Make or Ruby's Rake. If you've ever built projects with Rake, you'll be very at home using Jake
Jake has the following features:
- Jakefiles are in standard JavaScript syntax
- Tasks with prerequisites
- Namespaces for tasks
- Async execution of tasks
Requirements: Jake requires Node.js. Of course.
Get Jake:
git clone git://github.com/mde/node-jake.git
Build Jake:
cd node-jake && make && sudo make install
Or install with NPM:
npm install jake
(Or, get the code, and npm link in the code root.)
jake [options] target (commands/options ...)
You can see what other options Jake supports by doing jake -h or jake --help Probably the most important option starting off is the -T or --tasks option that lets you see what tasks are defined in a Jakefile.
You define your build tasks in a Jakefile.js (usually in the root of your project) -- by default the jake command looks for a Jakefile in the current directory, but you can also point Jake at a specific file using the -f (--jakefile) flag.
In your Jakefile, call task to define tasks. Call it with three arguments (and one more optional argument):
task(name, dependencies, handler, [async]);
Where name is the string name of the task, dependencies is an array of the dependencies, and handler is a function to run for the task.
Here's an example:
<intro-to-jake/sample-jakefile.js>
This is a build tool for Node, so of course we want to support async execution, right? The async argument is optional, and when set to true (async === true) indicates the task executes asynchronously. Asynchronous tasks need to call complete() to signal they have completed.
Here's an example of an asynchronous task:
<intro-to-jake/async-jakefile.js>
Use desc to add a string description of the task.
Use namespace to create a namespace of tasks to perform. Call it with two arguments:
namespace(name, namespaceTasks);
Where is name is the name of the namespace, and namespaceTasks is a function with calls inside it to task or desc defining all the tasks for that namespace.
Here's an example:
<intro-to-jake/namespace-jakefile.js>
In this example, the foo:baz task depends on both the 'default' and the 'foo:bar' task.
Run these namespaced tasks with jake [namespace]:[task]. The above example would be run with:
jake foo:baz
You can pass either positional or named parameters to Jake tasks (well, 'named parameters,' the JavaScripty way, in an Object).
Single parameters passed to the jake command after the task name are passed along to the handler as positional arguments.
So you can see this in action, let's set up an 'awesome' task that does nothing but print out the arguments it gets:
desc('This is an awesome task.');
task('awesome', [], function () {
console.log(sys.inspect(Array.prototype.slice.call(arguments)));
});
With this example, running jake like this:
jake awesome foo bar baz
You'd get the following output:
[ 'foo', 'bar', 'baz' ]
Paramters passed to the jake command that contain a colon (:) or equals sign (=) will be added to a keyword/value object that is passed as a final argument to the handler.
With the above Jakefile, you could run jake like this:
jake awesome foo bar baz qux:zoobie frang:asdf
And you'd get the following output:
[ 'foo'
, 'bar'
, 'baz'
, { qux: 'zoobie', frang: 'asdf' }
]
As you might expect if you're used to Make or Rake, running jake with no arguments runs the default task.
James Coglan's "Jake": http://github.com/jcoglan/jake
Confusingly, this is a Ruby tool for building JavaScript packages from source code.
280 North's Jake: http://github.com/280north/jake
This is also a JavaScript port of Rake, but it runs on the JVM-based Narwhal platform.