Automate war file creation with Grunt and Maven

The servers I am currently working on use Tomcat and accept war files for deploying my front-end Angularjs apps. I am building an Angularjs app using Yeoman, which doesn't build war files. To get around this I installed Grunt-Shell and modified my Gruntfile.js so it called Maven at the end of the build and created a war file out of the dist folder.

The biggest challenge was modifying the default Yeoman installation so that the Gruntfile.js put the distribution files in a folder structure that Maven accepted. Then adding a pom.xml file and calling Maven created the war file I needed.

How to call Maven from Grunt

• Install Maven2. In Ubuntu you can apt-get install maven2
• Install Grunt-Shell in your project npm install --save-dev grunt-shell
• Add the WEB-INF and META-INF folders and files to your project, so they are included in the distribution.
• In your projects Gruntfile.js change the configuration paths to match the Maven defaults
    // configurable paths
  var yeomanConfig = {
    app: 'app',                            //source files
    dist: 'dist/src/main/webapp',  //deploy location
    maven: 'dist'                        //pom.xml will go here
  };
  This creates a distribution folder structure that satisfies the Maven defaults.
  appHome
  |-app
  |-dist
    |-src
    |  |-main
    |    |-webapp
    |      |-META-INF
    |      |  |-context.xml
    |      |-WEB-INF
    |      |  |-web.xml
    |      |-(...distribution files)
    |-pom.xml
• Add the pom.xml to the copy section
  copy: {
...
      maven: {
        files: [{
          expand: true,
          dot: true,
          cwd: '<%= yeoman.app %>',
          dest: '<%= yeoman.maven %>',
          src: [
            'pom.xml',
          ]
        }]
      },
...
• Create the maven shell script
      shell: { 
      maven: {                               // build war file
            options: {                       // Options
                stdout: true,
                execOptions: {
                    cwd: 'dist'
                }
            },
            command: 'mvn clean install'
      }
    }
• Before the grunt.registerTask section register grunt-shell by adding grunt.loadNpmTasks('grunt-shell');
• Finally, call the maven task by adding
    grunt.registerTask('build', [
...
    'copy:maven',
    'shell:maven'
  ]);

UPDATE: 12/11/2013 there is a node package, grunt-war, that will do this https://npmjs.org/package/grunt-war