chajs / cha

Make task chaining.

cha

Make task chaining.

Cha allows tasks to be connected together into a chain that makes better readability and easier to maintain.

Getting Started

Installing cha via NPM, this will install the latest version of cha in your project folder and adding it to your devDependencies in package.json:

npm install cha --save-dev

Touch a tasks file and naming whatever you love like build.js:

// Load cha library.
var cha = require('cha')

// Register tasks that should chaining.
cha.in('glob',     require('task-glob'))
    .in('combine', require('task-combine'))
    .in('replace', require('task-replace'))
    .in('writer',  require('task-writer'))
    .in('uglifyjs',require('task-uglifyjs'))
    .in('copy',    require('task-copy'))
    .in('request', require('task-request'))

// Define task via chaining calls.
cha()
    .glob({
        patterns: './fixtures/js/*.js',
        cwd: __dirname
    })
    .replace({
        search: 'TIMESTAMP',
        replace: +new Date
    })
    .replace({
        search: /DEBUG/g,
        replace: true
    })
    .request('http://underscorejs.org/underscore-min.js')
    .combine()
    .uglifyjs()
    .writer('./out/foobar.js')
    .copy('./out/foobar2.js')

Add a arbitrary command to the scripts object:

{
  "name": "cha-example",
  "scripts": {
    "build": "node ./build.js"
  },
  "devDependencies": {
    "cha": "~0.1.0"
  }
}

To run the command we prepend our script name with run:

$ npm run build

> [email protected] build
> node ./test/build

request http://underscorejs.org/underscore-min.js
concat ./test/fixtures/bar.js,./test/fixtures/foo.js,http://underscorejs.org/underscore-min.js
write ./out/foobar.js
copy out/foobar.js > ./out/foobar2.js

Cha Extensions

• cha-load - Automatically load cha and register tasks.
• cha-watch - File watcher.
• cha-target - Target runner.
• cha-gulp - Gulp plugin adapter.

Cha Expressions

// Load cha library.
var cha = require('cha')

// Register tasks that should chaining.
cha.in('glob',     require('task-glob'))
    .in('combine', require('task-combine'))
    .in('replace', require('task-replace'))
    .in('writer',  require('task-writer'))
    .in('uglifyjs',require('task-uglifyjs'))
    .in('request', require('task-request'))

// Start with cha expressions.
cha(['glob:./fixtures/js/*.js', 'request:http://underscorejs.org/underscore-min.js'])
    .replace({
        search: 'TIMESTAMP',
        replace: +new Date
    })
    .replace({
        search: /DEBUG/g,
        replace: true
    })
    .combine()
    .uglifyjs()
    .writer('./test/out/foobar.js')

To run the command we prepend our script name with run:

$ npm run expr

> [email protected] expr
> node ./test/expr

request http://underscorejs.org/underscore-min.js
concat http://underscorejs.org/underscore-min.js
write ./out/foobar.js

Task Settings

// Load cha library.
var cha = require('cha')

// Register tasks that should chaining.
cha.in('glob',     require('task-glob'))
    .in('writer',  require('task-writer'))
    .in('uglifyjs',require('task-uglifyjs'))
    .in('request', require('task-request'))

// Start with cha expressions.
cha()
    .glob({
        patterns: './fixtures/js/*.js'
    })
    .request({
        url: 'http://underscorejs.org/underscore.js'
    }, {
        ignore: true, // Ignore task inputs.
        timeout: 2000 // 2000ms timeout.
    })
    .uglifyjs()
    .writer('./underscore-min.js')

JavaScript Tasks

All register task should based on the JavaScript Task specification. You could get available tasks from [JavaScript Task Packages] (http://taskjs.github.io/packages/) website.

Release History

• 2014-05-19 0.2.1 Task accept settings param with general options.
• 2014-05-18 0.2.0 Remove Internal methods.
• 2014-03-17 0.1.2 Extensions for cha.
• 2014-03-10 0.1.1 Custom tasks could override internal methods.
• 2014-03-05 0.1.0 Initial release.

cha's Issues

Future design

Hi there, just want to know what are the use cases for this library?

• If you want to have a task runner, there is grunt
• If you want to have a fast build tool with nested dependencies using streams, there is gulp
• If you like virtual build paths you could try fez
• Something more tree-based (seems to be a mix between grunt and fez) would be broccoli
• Mimosa is fast, very flexible and very solid, but has a bigger overhead if only being used as build tool

So now I'm trying to understand, what are the use cases for this library?

For my opinion, these are the problems with the current libraries:

• Grunt is very widely spread, but slow because of high IO.
• Gulp is very fast, but lacks in a lot of plugins that are missing.
• Fez seems to be even more dynamic, but it's very young and not widely known.
• Broccoli seems to be good for using Trees, which means you don't treat one single input stream but rather a bundle of them
• Mimosa handles RequireJS, linting, testing and all that stuff in the correct order without you needing to step in in most cases, but still provides a config to setup some special rules for your app.

Would love to get some clarifications, thanks!