Grunt.js and imagemin - No “imagemin” targets found

Question

I'm trying to teach myself the basics of Grunt.js and I'm finding it anything but intuitive.

I've got it working to a point - I'm able to watch the directory, minifiy JS and compile my compass / sass files.

The problem I'm now having is minifying images using: https://npmjs.org/package/grunt-contrib-imagemin

I keep getting the following error when running $ grunt:

No "imagemin" targets found

I've got my gruntfile here: https://github.com/Tjobbe/sample-grunt-project/blob/master/gruntfile.js and my git repo here: https://github.com/Tjobbe/sample-grunt-project so you can see my directory set up.

Any idea why this isn't working? Ideally I'd want it to continually poll the directory to see if there's any new files, then minify them and put them into the src/img/ directory.

Answer 1

Your imagemin is a subtask of your watch task. If you take it out, it'll work.

Here's part of the Gruntfile.js

        watch: {
        compass: {
            files: ['dev/sass/*.sass'],
            tasks: ['compass:dev']
        },
        js: {
            files: ['dev/js/*.js'],
            tasks: ['uglify']
        }
    },
    compass: {
        dev: {
            options: {
                sassDir: ['dev/sass/'],
                cssDir: ['src/css/'],
                environment: 'development'
            }
        },
        prod: {
            options: {
                sassDir: ['dev/sass/'],
                cssDir: ['src/css/'],
                environment: 'production'
            }
        },
    },
  imagemin: {
    dynamic: {
      files: [{
        expand: true,
        cwd: 'dev/img/',
        src: ['dev/img/*.{png,jpg,gif}'],
        dest: 'src/img/'
      }]
    }
  },
    uglify: {
        all: {
            files: {
                'src/js/min.js': [
                'dev/js/*.js']
                // 'js/*.js']
            }
        },
    },
});

Answer 2

imagemin is a subtask of watch. As of this you need to call it like this watch:imagemin

The same way as you used compass:dev