ready-callback

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[![npm download][download-image]][download-url]

[npm-image]: https://img.shields.io/npm/v/ready-callback.svg?style=flat-square
[npm-url]: https://npmjs.org/package/ready-callback
[codecov-image]: https://codecov.io/github/node-modules/ready-callback/coverage.svg?branch=master
[codecov-url]: https://codecov.io/github/node-modules/ready-callback?branch=master
[download-image]: https://img.shields.io/npm/dm/ready-callback.svg?style=flat-square
[download-url]: https://npmjs.org/package/ready-callback

Launch server after all async task ready

---

Install

``bash
$ npm install ready-callback
`

Usage

Note: ready-callback is using class, so you should use node>=2

`js
var koa = require('koa');
var ready = require('ready-callback')();
var app = koa();
ready.mixin(app);

// register a service
var done = app.readyCallback('service');
serviceLaunch(done);

// callback will be fired after all service launched
app.ready(function() {
app.listen();
});
`

$3

If task is called with error, error event will be emit, ready will never be called.

`js
// register a service that will emit error
var done = app.readyCallback('service');
serviceLaunch(function(err) {
done(err);
});

// listen error event
app.on('error', function(err) {
// catch error
});
`

$3

If you set a task weak dependency, task will be done without emit error.

`js
var done = app.readyCallback('service', {isWeakDep: true});
serviceLaunch(function(err) {
done(err);
});

// will be ready
app.ready(function() {
app.listen();
});

app.on('error', function(err) {
// never be called
});
`

You can also set for all ready-callback

`js
var ready = require('ready-callback')({isWeakDep: true});
`

$3

You can get status every callback end.

`js
app.on('ready_stat', function(data) {
console.log(data.id); // id of the ended task
console.log(data.remain); // tasks waiting to be ended
});
`

$3

You can set timeout when a task run a long time.

`js
var ready = require('ready-callback')({timeout: 1000});
ready.mixin(app);
app.on('ready_timeout', function(id) {
// this will be called after 1s that service task don't complete
});

var done = app.readyCallback('service');
serviceLaunch(function() {
// run a long time
done();
});
`

You can also set timeout for every task

`js
ready.mixin(app);
app.on('ready_timeout', function(id) {
// this will be called after 1s that service task don't complete
});

var done = app.readyCallback('service1', {timeout: 1000});
serviceLaunch(done);
`

$3

You can set a ready-callback object to lazyStart. It will not check
ready status immediately, and should start manualy to check ready
status.

`js
var ready = require('ready-callback')({ lazyStart: true });
yield sleep(1);
// ready obj is not ready
ready.start();
yield sleep(1);
// ready obj is ready now
``

LISENCE

Copyright (c) 2015 popomore. Licensed under the MIT license.