How to setup a grunt file to watch and compile less files - node.js

Question

I'm trying to use grunt to compile my less files into css while in development. While at it also, watch and reload. The file I've wrote is this:
module.exports = function(grunt) {
grunt.initConfig({
less: {
development: {
options: {
compress: true,
yuicompress: true,
optimization: 2
},
files: {
// target.css file: source.less file
"public/css/bootstrap.css": "./public/less/bootstrap.less"
}
}
},
watch: {
styles: {
// Which files to watch (all .less files recursively in the less directory)
files: ["public/less/*"],
tasks: ['less'],
options: {
livereload: true,
}
}
}
});
grunt.loadNpmTasks('grunt-contrib-less');
grunt.loadNpmTasks('grunt-contrib-watch');
grunt.registerTask('default', ['watch']);
};
And I have this saved as a gruntfile.js in my project root's directory. What am I doing wrong?
PS: I'm using forever to start my app and in the same terminal window I'm using the command grunt watch, however when I change my less files nothing happens.
PPS: My file structure is as follows:
root
-- public
-- less
-- css
As you can see above my main less file is located at root/public/less/bootstrap.less and I'd like the css to be compiled at root/public/css/bootstrap.css
Many thanks

Answer 1

Your setup seems to be good but I found a problem here... may be it solves your Question
"public/css/bootstrap.css": "./public/less/bootstrap.less"
^^
your url is same but in second appearance you have add extra "./" I think if you remove this it will work.
This is my own code and it is working fine.
module.exports = function(grunt){
grunt.initConfig({
//pkg:grunt.file.readJSON('package.json'),
less:{
development:{
options:{
compress: true,
yuicompress: true,
optimization: 2
},
files:{
'webroot/css/meer/index/index2.css' : 'webroot/css/meer/index/index2.less'
}
}
},
watch: {
styles:{
options:{
livereload: true,
spawn: false,
event: ['added','deleted','changed']
},
files:['webroot/css/meer/index/*.less'],
tasks:['less']
}
}
});
grunt.loadNpmTasks('grunt-contrib-less');
grunt.loadNpmTasks('grunt-contrib-watch');
grunt.registerTask('default',['watch']);
}