co-tasks

Task or hook runner using co. Runs an array of tasks in series.

.run([tasks], [ctx], [args], [timeout])

 
var TaskRunner = require('co-tasks');
var taskRunner = new TaskRunner();
 
// Add tasks
taskRunner.registerTask('foo', function(done) {
    console.log('Foo one');
    done();
});
 
taskRunner.registerTask('foo', function(done) {
    console.log('Foo two');
    done();
});
 
taskRunner.registerTask('pre-foo', function(done) {
    console.log('Start');
    done();
});
 
taskRunner.registerTask('post-foo', function(done) {
    console.log('After foo');
    done();
});
 
taskRunner.registerTask('finish', function(done) {
    console.log('Finish');
    done();
});
 
// Call tasks
 
taskRunner.run(['foo', 'finish']);
 
// You'll see, pre-* and post-* tasks will be calling as well
// Output
 
Start
Foo one
Foo two
After foo
Finish
 

.pipe([tasks], [ctx], pipeObj, [timeout])

Runns tasks in series, pipes pipeObj through all tasks in series

tasks Task names, this can be optional if allowedTasks option is set.
ctx This context
pipeObj Pipe through object
timeout Timpout in milliseconds. Defaults to 30000

yieldables

We call yieldable a function, a generator or a promise, supported by co-task.

Promises

taskRunner.registerTask('foo', new Promise(function(resolve, reject) {
    resolve('apple');
});

Generators

taskRunner.registerTask('foo', function *() {
    return 'banana';
}

Callback functions

taskRunner.registerTask('foo', function(done) {
    done(null, 'coconut');
}

Callbacks with promises

taskRunner.registerTask('foo', function(promise) {
    promise.resolve('date');
}

Promise returning functions

taskRunner.registerTask('foo', function(promise) {
    return Promise.resolve('elderberry');
}

Call it all together

taskRunner.run(['foo']).then(function(result) {
    console.log(result);
 
    // result === [
    //     {
    //         task: 'foo',
    //         results: ['apple', 'banana', 'coconut', 'date', 'elderberry']
    //     }
    // ]
}).catch(function(err) {
    // Error handling
});

Arguments and this context

Passing arguments or a this context to yieldable is very easy. co-tasks accepts a this context as second parameter and an arguments array as third parameter. Both of them are optional.

let ctx = {
    prefix: '#'
};
 
let args = ['apple', 'banana'];
 
taskRunner.registerTask('foo', function *(arg1, arg2) {
    return this.prefix + arg1;
});
 
taskRunner.registerTask('foo', function *(arg1, arg2) {
    return this.prefix + arg2;
});
 
taskRunner(['foo'], ctx, args).then(function(result) {
    //result contains
    [{
        task: 'foo',
        results: ['#apple', '#banana']
    }]
}).catch(function(err) {
    // Error handling
});

Timeout

co-tasks timeouts after 30 seconds by default. The timeout can be changed by passing a number of milliseconds as fourth or last parameter

var promise = taskRunner(['foo'], ctx, args, 500);