Run async task and wait for it - asynchronous

Question

If I do the following:
module.exports = function(grunt) {
grunt.initConfig({
pkg: grunt.file.readJSON('package.json'),
});
grunt.registerTask('myAsync','An async test task',function(){
var done = this.async();
setTimeout(function(){
console.log('This is my async task');
done();
},1000);
});
grunt.registerTask('myTask','A test task',function(){
grunt.task.run('myAsync');
console.log('This is my task');
});
grunt.registerTask('default', ['myTask']);
};
The output is:
Running "myTask" task
This is my task
Running "myAsync" task
This is my async task
So 'myTask' is not waiting for 'myAsync' to finish. I would like 'myTask' to wait for 'myAsync'. Came up with the following but not sure it this is the way to do it:
module.exports = function(grunt) {
// Project configuration.
grunt.myAsync = function myAsync(callback){
var done = this.async();
setTimeout(function(){
console.log('This is my async task');
callback();
done();
},1000);
};
grunt.initConfig({
pkg: grunt.file.readJSON('package.json'),
});
grunt.registerTask('myAsync','An async test task',function(){
grunt.myAsync();
});
grunt.registerTask('myTask','A test task',function(){
var done = this.async();
console.dir(this);
grunt.myAsync.call(this,function(){
console.log('This is my task');
done();
});
});
// Default task(s).
grunt.registerTask('default', ['myTask']);
};
It allows me to either let grunt run 'myAsync' or run it from another task and wait for it.
Is there another way of doing this? Could not find how to wait for async tasks when calling them from a task.
[UPDATE]
Kyle got me on the right track, have added 3 tasks; 1 drop db, 2, run test, 3 run tests and drop db. Since tasks run in queue the 3rd task only has to run the other 2. Instead of having the first task (run tests) call the second task (drop db).
It looks something like this:
grunt.registerTask('runtests','Runs the integration tests.',function(){
var done = this.async();
setTimeout(function(){
console.log('ran the tests db');
done();
},100);
});
grunt.registerTask('dropdb','Drops the db.',function(){
var done = this.async();
setTimeout(function(){
console.log('droped db');
done();
},100);
});
grunt.registerTask('dropandrun','Runs the integration tests.',function(){
if(!grunt.option('nodrop')){
grunt.task.run('dropsdb');
}
grunt.task.run('runtests');
});

Answer 1

Grunt runs tasks in a queue. So if you queue a task within another task with grunt.task.run(), it will run that task after the current has finished.
Rather than adding methods to the grunt instance itself, you can create your own functions and libraries your tasks can call. Such as like this:
module.exports = function(grunt) {
function myAsync(callback){
setTimeout(function(){
console.log('This is my async task');
callback();
},1000);
}
grunt.initConfig({
pkg: grunt.file.readJSON('package.json'),
});
grunt.registerTask('myAsync','An async test task',function(){
myAsync(this.async());
});
grunt.registerTask('myTask','A test task',function(){
var done = this.async();
myAsync(function() {
console.log('This is my task');
done();
});
});
grunt.registerTask('default', ['myTask']);
};
Later as those functions grow you can move them into their own file and use them like this:
// ./lib/myasync.js
module.exports = function(callback) {
setTimeout(function() {
console.log('This is my async function');
callback();
}, 1000);
};
...
// Gruntfile.js
var myAsync = require('./lib/myasync.js');