Watching for changes on source-files and rebuild them. Say no to grunt and co.

build_watcher.js

'use strict';

/*
# Build-environment filewatcher-script

 */
const chokidar = require('chokidar');
const child_process = require('child_process');
const Path = require('path')
const config = require('./watch.conf');


/*
## JadeWatcher
Watching for files in the template-source-directory.
These files are going to be rendered in the front-end, so they have to be
precompiled to a function.
Look at env/client_jade.js for details about this process.
 */
const jadeWatcher = chokidar.watch(config.jade.in, { persistent: true });

var compileJade = function(action, path){
  console.log(`Jade: ${action} on ${path}`);
  let cmd = `node env/client_jade ${config.jade.in} ${config.jade.out}`
  child_process.exec(cmd,function(err, stdout, stderr){
    if(err) {
      console.error("JadeWatcher error:");
      console.error(err);
    }
    if(stderr) {
      console.error("Jade compile-error:");
      console.error(stderr);
    }
    console.log("Jade compiler-output:");
    console.log(stdout);
  });
}

jadeWatcher
  .on('all', compileJade)

/*
## StylusWatcher
Watching for files in the stylesheets-source-directory and recompile the
index.styl-file on changes.
 */

const stylusWatcher = chokidar.watch(config.stylus.in,{ persistent: true });

var compileStylus = function(action, path){
  console.log(`Stylus: ${action} on ${path}`);
  let cmd = "node node_modules\\stylus\\bin\\stylus"
  cmd += ` source\\stylesheets\\index.styl ${config.stylus.in}\\`;
  cmd += config.stylus.main;
  config.stylus.libs.forEach(function(lib){
    cmd += ` -u ${lib}`;
  });
  cmd += ` --out ${config.stylus.out}`;
  child_process.exec(cmd, function(err, stdout, stderr){
    if(err) {
      console.error("StylusWatcher error:");
      console.error(err);
    }
    if(stderr) {
      console.error("Stylus compile-error:");
      console.error(stderr);
    }
    console.log("Stylus compiler-output");
    console.log(stdout)
  });
}

stylusWatcher.on('all', compileStylus);

/*
## BrowserifyWatcher
Watch for changes on client-javascript in their source dir and and let
browserify rebuild them.
 */

const browserifyWatcher = chokidar.watch(config.browserify.in, {
  persistent: true
});

var rebuildJavascripts = function(action,path){
  console.log(`Browserify: ${action} on ${path}`);
  let cmd = `node node_modules\\browserify\\bin\\cmd `;
  cmd += `${config.browserify.in}\\main.js -o `;
  cmd += `${config.browserify.out}\\main.js`;
  child_process.exec(cmd, function(err, stdout, stderr){
    if(err){
      console.error("BrowserifyWatcher error:");
      console.error(err);
    }
    if(stderr){
      console.error("Browserify compile-error:");
      console.error(stderr);
    }
    console.log("Rebuilt client-javascript");
  })
}

browserifyWatcher.on('all', rebuildJavascripts);

watch.conf.json

{
  "jade": {
    "in": "source/templates",
    "out": "source/javascripts/template.js"
  },
  "stylus": {
    "in": "source/stylesheets",
    "out": "public/css",
    "main": "index.styl",
    "libs": ["nib","jeet","rupture"]
  },
  "browserify": {
    "in": "source/javascripts",
    "out": "public/js"
  }
}