grunt-contextualize

This plugin overrides configuration properties based on the current context, in order to re-use a single set of plugin targets for multiple contexts.

This is particularly useful when a plugin is already configured with multiple targets -- for example, to create one JavaScript or CSS file for the whole site, and one for each set of pages on a complex site. In these cases, creating and maintaining a distinct configuration for each combination of components (e.g. site-wide vs. home page) with build configurations (development vs. distribution) is burdensome.

This plugin supports three modes (which can be mixed and matched):

1. Contextual properties override the values of properties they're next to. For example, options: {pretty: true; pretty$release: false} in a plugin configuration lets the corresponding plugin task see pretty as true when the contextualize task isn't run, but as false when the task follows the contextualize:release task.
2. With local configuration, contexts are specified inside each plugin's configuration, alongside the values that are being modified. For example, options: {pretty: true; _release: {pretty: false}}.
3. With a global configuration, contexts are specified inside the contextualize section of the grunt configuration, and their values are copied into other tasks' configurations.

See the bottom of this README for examples of using each mode to modify SASS and Jade configurations.

Alternatives:

• Grunt templates work great when the configuration property is a string. Unfortunately, templates can't expand into non-string values, such as boolean flags.
• Grunt options are available when grunt.initConfig is called, and can therefore be used outside of string interpolation. However, the use of options requires that you specify them as command-line options, in conjunction with the task target(s), in the grunt command line. Unfortunately, command-line options can't be encapsulated in the target definitions. (A target can set option values, but then it's too late for this to affect configuration defined in the initial call to grunt.initConfig.)
• I wanted grunt-context to work, but its author says it's defunct. In time-honored weekend project manner, I decided I'd rather write my own with a different features than understand how to fix it.
• grunt-reconfigure handles the "global configuration" case. I didn't discover that plugin until after I had written this one, and had decided I liked the contextual properties and local configuration by then.

Getting Started

This plugin requires Grunt ~0.4.x

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-contextualize --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:

grunt.loadNpmTasks('grunt-contextualize');

The "contextualize" task

Overview

In your project's Gruntfile, do one or more of the following.

With any of these configurations:

• The contextualize:context1 task will replace the value of somePlugin.options.anOption by 1; and
• the contextualize:context2 task will replace the value of somePlugin.options.anOption by 2.

Contextual Properties

Sprinkle properties named "#{propertyName}$#{context}" into your grunt configuration.

grunt.initConfig({
  somePlugin: {
    options: {
      anOption: 0
      anOption$context1: 1
      anOption$context2: 2
    },
})

Local configuration

Add properties named e.g. '_context1' ('_' plus a context name) alongside the configuration options for other plugins.

This context property can be inside the object that contains the properties it replaces:

grunt.initConfig({
  somePlugin: {
    options: {
      anOption: 0
      _context1: {
        anOption: 1
      },
      _context2: {
        anOption: 2
      }
    }
  }
})

Or it can be inside a parent of this object:

grunt.initConfig({
  somePlugin: {
    options: {
      anOption: 0
    },
    _context1: {
      options: {
        anOption: 1
      }
    },
    _context2: {
      options: {
        anOption: 2
      }
    }
  }
})

Global Configuration

Add a section named contextualize to the data object passed into grunt.initConfig().

grunt.initConfig({
  contextualize: {
    options: {
      // Task-specific options go here.
    },
    context1: {
      target1: {
        property1: 'replacement 1'
      }
    },
    context2: {
      target1: {
        property1: 'replacement 2'
      }
    }
  }
})

Options

options.infix

Type: String Default value: '$'

The separator between a contextualized property and its context. Where contextualize looks for 'name$context1' in the examples, a value of '_' for options.prefix would cause it to look for 'name_context1' instead.

'.' or ':' would be nice infix values, but using them would require you to quote your property names; e.g. {'name.context1': ...} instead of {name.context1: ...}.

options.prefix

Type: String Default value: '_'

The values keyed by property names that begin with this prefix are merged into nearby data. Where contextualize looks for '_context1' in the examples, a value of '$' for options.prefix would cause it to look for '$context1' instead.

'.' or ':' would be nice prefix values, but using them would require you to quote your property names; e.g. {':context1': ...} instead of {_context1: ...}. Also, '_' has the feature that grunt ignores it when used at the top level of a multitask configuration, where it could otherwise be mistaken for the name of a multitask target.

options.verbose

Type: boolean Default value: false

Display information about which properties are replaced. This has the same effect on this plugin as the --verbose option to grunt does, but unlike that option it only affects this plugin.

Usage Examples

Local Configurations

In this example, grunt build will build jade files with the pretty option, and uncompressed sass files with sourcemap. into the build directory. grunt build:release will build jade files without pretty, and compressed sass files without sourcemap, into the release directory.

grunt.initConfig({
  directories: {
    build: '<%= directories.dev %>',
    dev: 'build',
    release: 'release',
    _release: {
      build: '<%= directories.release %>'
    }
  },
 
  jade: {
    app: {
      expand: true,
      cwd: 'app',
      src: '**/*.jade',
      dest: '<%= directories.build %>',
      ext: '.html'
    }
    options: {
      pretty: true,
      _release: {
        pretty: false
      }
    }
  },
 
  sass: {
    app: {
      expand: true,
      cwd: 'app',
      dest: '<%= directories.build %>',
      src: ['css/**.scss', '!css/_*'],
      ext: '.css',
      filter: 'isFile'
    }
    options: {
      sourcemap: true,
      _release: {
        sourcemap: false
        style: 'compressed'
      }
    }
  }
})
 
grunt.registerTask 'build', ['jade', 'sass']
grunt.registerTask 'build:release', ['context:release', 'build']

Global Configuration

This configuration has the same effect as the preceding example.

grunt.initConfig({
  contextualize: {
    release: {
      directories: {
        build: '<%= directories.release %>'
      },
      jade: {
        app: {
          options: {
            pretty: false
          }
        }
      },
      sass: {
        app: {
          options: {
            sourcemap: false
            style: 'compressed'
          }
        }
      }
    }
  }
  directories: {
    build: '<%= directories.dev %>',
    dev: 'build',
    release: 'release'
  },
 
  jade: {
    app: {
      expand: true,
      cwd: 'app',
      src: '**/*.jade',
      dest: '<%= directories.build %>',
      ext: '.html'
    }
    options: {
      pretty: true
    }
  },
 
  sass: {
    app: {
      expand: true,
      cwd: 'app',
      dest: '<%= directories.build %>',
      src: ['css/**.scss', '!css/_*'],
      ext: '.css',
      filter: 'isFile'
    }
    options: {
      sourcemap: true
    }
  }
})
 
grunt.registerTask 'build', ['jade', 'sass']
grunt.registerTask 'build:release', ['context:release', 'build']

See this project's Gruntfile for additional (CoffeeScript) examples.

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.

Release History

• September 24, 20012 -- initial release