Using output of one task as an input for another

Question

I have an html file that contains references to js files. I want to parse it extract a list of referenced js files and feed contrib-concat or any other task with them. Is there any convenient way to use output of one grunt task as an input for another?

Answer 1

Use grunt.config. Here is an example:

grunt.initConfig({
  concat: {
    js: {
      src: ['default/concat/files/*'],
      dest: ['dist/javascript.js'],
    },
  },
});
grunt.registerTask('extractjs', function() {
  /* Do the js extraction */
  // Overwrite the concat.js.src with your extracted files.
  grunt.config(['concat', 'js', 'src'], extractedFiles);
});

So now when you run grunt extractjs concat it will extract the js and then concat the extracted js files. Check out this task: https://github.com/cgross/grunt-dom-munger as he is working on a similar goal. Here is a grunt issue with more examples as well: https://github.com/gruntjs/grunt/issues/747