Gulp task for a express, nodemon, livereload, angularjs application

gulp_nodemon_webpack_livereload.js

// watches all js and css files
// if a file is in the public folder
// runs a task based on the file extension and the file path
gulp.task("nodemon", function(){

  // start livereload
  livereload.listen();

  nodemon({
  
    // node app entry point
    script: './index.js',
    
    // extensions to watch changes for
    ext: "js scss",
    
    // watch folders
    watch: [
      './lib/*',
      './public/js/app/*',
      './public/scss/*'
    ],
    
    // pass enviromental variable to node app
    env: { 
      'NODE_ENV': 'development'
    },
    
    // when a change is detected this function runs and returns an array of tasks
    // based on file extension and file path
    tasks: function(changedFiles){
      var tasks = [];

      changedFiles.forEach(function(file){
        if(file.match(/public/)){
          if (path.extname(file) === '.js' && tasks.indexOf('webpack') == -1) {
              tasks.push('webpack');
          }

          if (path.extname(file) === '.scss' && tasks.indexOf('sass') == -1){
              tasks.push('sass')
          }
        }
      });
      
      // push livereload to the tasks to be performed
      tasks.push('livereload');
      
      return tasks;
    }
  }).on('restart', function(){
    console.log('Server restarted');
  });
});