Gruntfile.js

var TEST_CONFIG = {
  appName: 'whysaurustest',
  appVersion: 'a'
};

var STAGING_CONFIG = {
  appName: 'whysaurus',
  appVersion: 'c',
};

var PROD_CONFIG = {
  appName: 'whysaurus',
  appVersion: 'a',
};

var preprocessAppYaml = function(config) {
  return {
    src : 'app.yaml.stub' ,
    dest: 'app.yaml',
    options: { inline : true, context : config }
  };
};

module.exports = function(grunt) {
  // configure the tasks
  grunt.initConfig({
    clean: {
      main: {
        src: [ 'app.yaml' ],
      },
    },

    preprocess: {
      test: preprocessAppYaml(TEST_CONFIG),
      staging: preprocessAppYaml(STAGING_CONFIG),
      prod: preprocessAppYaml(PROD_CONFIG),
    },

    shell: {
      local: {
        command: 'dev_appserver.py --skip_sdk_update_check --host localhost --port 8081 --admin_host localhost .',
        options: {
          async: false,
        },        
      }      
    },
    gae: {
        options: {
            auth: './gae.auth'
        },
        test: {
            action: 'update',
            options: {
                application: 'whysaurustest',
                version: 'a'
            }
        },
        staging: {
            action: 'update',
            options: {
                application: 'whysaurus',
                version: 'c'
            }
        },
        live: {
            action: 'update',
            options: {
                application: 'whysaurus',
                version: 'a'
            }
        }
    }
  });

  // load the tasks
  grunt.loadNpmTasks('grunt-autoprefixer');
  grunt.loadNpmTasks('grunt-contrib-clean');
  grunt.loadNpmTasks('grunt-preprocess');
  grunt.loadNpmTasks('grunt-shell-spawn');
  grunt.loadNpmTasks('grunt-gae');

  // define the tasks
  grunt.registerTask('local', 'Builds and deploys to the TEST appengine environment.',
                        [ 'clean', 'preprocess:test', 'shell:local' ]);
                   
  grunt.registerTask('test', 'Builds and deploys to the TEST appengine environment.',
                        [ 'gae:test' ]);
                        
  grunt.registerTask('staging', 'Builds and deploys to the STAGING appengine environment.',
                        [ 'gae:staging']);
                        
  grunt.registerTask('prod', 'Builds and deploys to the PROD appengine environment.',
                        [ 'gae:live' ]);

};