grunt-envtojson

Update a json object file with environment variable values.

Getting Started

This plugin requires Grunt ~0.4.4

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-envtojson --save-dev

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

grunt.loadNpmTasks('grunt-envtojson');

The "envtojson" task

Overview

In your project's Gruntfile, add a section named envtojson to the data object passed into grunt.initConfig().

grunt.initConfig({
  envtojson: {
    options: {
      vars: {
        ENV_VAR: "object.path.to.alter"
      }
    },
    your_target: {
      files: {
        'dest.js': ['src.js']
      }
    },
  },
});

Options

options.vars

Type: Object Default value: {} Description Map of environment variables to the json keys they should be injected into.

options.assignToVar

Type: String Default value: false Description Assign the output to this var. Pass a falsy value to just get the json.

options.whiteSpace

Type Int Default value: 4 Description Passed as the 3rd arg to JSON.stringify when writing out the object. Pass 0 for no formatting.

Map of environment vars to config keys.

Usage Examples

input

{
    foo: {
        bar: 'howdy'
    },
    spam: {
        eggs: {
            parrot: "grail"
        }
    },
    beer: "good"
}

grunt

envtojson: {
    options: {
        vars: {
            FOO_BAR: "foo.bar",
            PYTHONESQUE: 'spam.eggs.parrot',
            DRINK_BEER: 'beer',
            DYNAMIC_PROP: 'one.hundred.stones'
        }
        whiteSpace: 0
    },
    mytask: {
        files: {
            'tmp/default.js': ['test/fixtures/default.js']
        },
        options: {
            assignToVar: 'config'
        }
    }
}

Now set some shell vars and run

FOO_BAR=altered PYTHONESQUE=altered DRINK_BEER=altered DYNAMIC_PROP=newProp grunt envToson

output

config="foo": {
        "bar": "altered"
    },
    "spam": {
        "eggs": {
            "parrot": "altered"
        }
    },
    "beer": "altered",
    "one": {
        "hundred": {
            "stones": "newProp"
        }
    }
};

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

2.0.1 *Amend readme which I forgot to update for 2.0.0

2.0.0 *Change default value of assignToVar to false (was module.exports). breaking change.

1.0.1 *Add assignToVar option to assign output to an arbitrary variable *Add whiteSpace option to format the generated json

1.0.0 *first public release