Grunt task output then calling grunt-notify - node.js

Question

Grunt notify: https://github.com/dylang/grunt-notify is great. However, it seems a bit limited. As far as I can tell all my messages need to be pre-generated. So the first question is how can I generate notifications?
Next, It seems that grunt notify triggers based on error or success of some task. I guess based on std in/out/err? The problem where this breaks down is if some task doesn't use these. grunt compass doesn't use stderr if there are compile errors. So how can I run grunt notify when it has an error? This then leads to the next question. How can I grab the console output or stderr from a grunt task?

Answer 1

First of all, use growl. It is easy and flexible to use. To install growl:
npm install growl --save-dev
Then you need to hook into the stderr/out stream of the process. This way you can create a notification each time a new message arrives at the stderr/out stream.
This is what I've created. I've made a CommonJs module which adds hooks to:
grunt.fail.warn(), grunt.fail.fatal()
grunt.log.warn(), grunt.log.error()
grunt.warn()
process.stderr.write()
process.stdout.write() (error lines)
(child) process.stderr.write()
(child) process.stdout.write() (error lines)
It works more or less, but it may need some tweaking.
tasks/lib/notify.js
(function (module) {
var grunt = require('grunt'),
growl = require('growl'),
Buffer = require('buffer').Buffer;
function notify(obj, title) {
if (obj) {
var message = Buffer.isBuffer(obj) ? obj.toString() : (obj.message || obj);
var msg = grunt.log.uncolor(message);
if (msg.length > 0) {
growl(msg, {
title: title,
image: 'Console'
});
}
}
}
// add a hook to grunt.fail.warn(), grunt.fail.fatal()
['warn', 'fatal'].forEach(function (level) {
grunt.util.hooker.hook(grunt.fail, level, function(obj) {
notify(obj);
});
});
// add a hook to grunt.log.warn(), grunt.log.error()
['warn', 'error'].forEach(function (level) {
grunt.util.hooker.hook(grunt.log, level, function(obj) {
notify(obj, level);
});
});
// add a hook to grunt.warn()
grunt.util.hooker.hook(grunt, 'warn', function(obj) {
notify(obj, 'warn');
});
// add a hook to process.stderr.write()
grunt.util.hooker.hook(process.stderr, 'write', function(obj) {
var messages = grunt.log.uncolor((Buffer.isBuffer(obj) ? obj.toString() : (obj.message || obj))).split('\n');
messages.forEach(function (message) {
notify(message, 'stderr');
});
});
// add a hook to process.stdout.write() (only error lines)
grunt.util.hooker.hook(process.stdout, 'write', function(obj) {
var messages = grunt.log.uncolor((Buffer.isBuffer(obj) ? obj.toString() : (obj.message || obj))).split('\n');
messages.forEach(function (message) {
if (message && message.indexOf('error ') > -1) {
notify(message, 'stdout');
}
});
});
// add a hook to child process stdout/stderr write() (only error lines)
grunt.util.hooker.hook(grunt.util, 'spawn', {
post: function(child) {
child.stderr.on('data', function (data) {
var messages = grunt.log.uncolor(data.toString()).split('\n');
messages.forEach(function (message) {
notify(message, 'stderr');
});
});
child.stdout.on('data', function (data) {
var messages = grunt.log.uncolor(data.toString()).split('\n');
messages.forEach(function (message) {
if (message && message.indexOf('error ') > -1) {
notify(message, 'stdout');
}
});
});
}
});
}) (module);
Then you need to include it in your Gruntfile.js with a require statement:
module.exports = function (grunt) {
grunt.initConfig({
...
});
require('./tasks/lib/notify');
...
};
PS I've placed the file in tasks/lib/notify.js, but feel free to place it somewhere else.