javascript - How do I configure different environments in Angular.js?

Question

How do you manage configuration variables/constants for different environments?

This could be an example:

My rest API is reachable on localhost:7080/myapi/, but my friend that works on the same code under Git version control has the API deployed on his Tomcat on localhost:8099/hisapi/.

Supposing that we have something like this :

angular
    .module('app', ['ngResource'])

    .constant('API_END_POINT','<local_end_point>')

    .factory('User', function($resource, API_END_POINT) {
        return $resource(API_END_POINT + 'user');
    });

How do I dynamically inject the correct value of the API endpoint, depending on the environment?

In PHP I usually do this kind of stuff with a config.username.xml file, merging the basic configuration file (config.xml) with the local environment configuration file recognised by the name of the user. But I don't know how to manage this kind of thing in JavaScript?

Answer 1

I'm a little late to the thread, but if you're using Grunt I've had great success with grunt-ng-constant.

The config section for ngconstant in my Gruntfile.js looks like

ngconstant: {
  options: {
    name: 'config',
    wrap: '"use strict";

{%= __ngModule %}',
    space: '  '
  },
  development: {
    options: {
      dest: '<%= yeoman.app %>/scripts/config.js'
    },
    constants: {
      ENV: 'development'
    }
  },
  production: {
    options: {
      dest: '<%= yeoman.dist %>/scripts/config.js'
    },
    constants: {
      ENV: 'production'
    }
  }
}

The tasks that use ngconstant look like

grunt.registerTask('server', function (target) {
  if (target === 'dist') {
    return grunt.task.run([
      'build',
      'open',
      'connect:dist:keepalive'
    ]);
  }

  grunt.task.run([
    'clean:server',
    'ngconstant:development',
    'concurrent:server',
    'connect:livereload',
    'open',
    'watch'
  ]);
});

grunt.registerTask('build', [
  'clean:dist',
  'ngconstant:production',
  'useminPrepare',
  'concurrent:dist',
  'concat',
  'copy',
  'cdnify',
  'ngmin',
  'cssmin',
  'uglify',
  'rev',
  'usemin'
]);

So running grunt server will generate a config.js file in app/scripts/ that looks like

"use strict";
angular.module("config", []).constant("ENV", "development");

Finally, I declare the dependency on whatever modules need it:

// the 'config' dependency is generated via grunt
var app = angular.module('myApp', [ 'config' ]);

Now my constants can be dependency injected where needed. E.g.,

app.controller('MyController', ['ENV', function( ENV ) {
  if( ENV === 'production' ) {
    ...
  }
}]);