GitHub - chajs/cha: Make task chaining.

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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

> cha@0.0.1 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 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

> cha@0.0.1 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.