cofy

Cofy is a bridge connecting callback style object to sequential style in co or koa environment with one punch.

##Installation

$ npm install cofy --save

NOTE: default prefix has changed to '$'.

Some examples

use cofy in redis.

'use strict';
var co = require("co");
var cofy = require("cofy");
var redis = require('redis');

//enable redis to has a co ablitiy.
cofy.class(redis.RedisClient);

//now we can use mysql in co 
var client = redis.createClient(6379,'localhost');
co(function * () {
	//use class.$fn
	var r1 = yield client.$set('a' ,1);
	var r2 = yield client.$get('a');
	var r3 = yield client.$hmset('h' , {k1:'v1' , k2:'v2'});
	var r4 = yield client.$hget('h' ,'k1');
	console.log(r1,r2);
	console.log(r3,r4);
})();

use cofy in mysql.

'use strict';
var co = require("co");
var cofy = require("cofy");
var mysql = require('mysql');

//(felixge/node-mysql) has no extends entrance. so we can do this.
var PoolConnection = require('mysql/lib/PoolConnection.js');
var Pool = require('mysql/lib/Pool.js');
var PoolCluster = require('mysql/lib/PoolCluster.js');

//enable mysql to has a co ablitiy.
cofy.class(PoolConnection);
cofy.class(Pool);
cofy.class(PoolCluster);

var pool = mysql.createPool({
	host: "localhost",
    database: "db",
    user: "root",
    password: "pass",
});
//now we can use mysql in co 
co(function * () {
	var con = yield pool.$getConnection();
	//pay attention on precedence of operator! yield < [] .
	var result = (yield con.$query("select 1+1"))[0]; 
	console.log(result);
	con.release();
})();


//use it in transaction
co(function*(){
	var con ;
	try{
		con = yield pool.$getConnection();
		yield con.$beginTransaction();
		yield con.$query("select some");
		yield con.$query("insert some");
		yield con.$query("update some");
		yield con.$commit();
	}catch(e){
		yield con.$rollback();
		console.error(e);
		//to do 
	}finally{
		if(con){
			con.release();
		}
	}
})();

use cofy in request.

'use strict';
var request = require('request');
var cofy = require('cofy');
var co = require('co');

var $request = cofy.fn(request);

co(function*(){
	var r = yield $request({url:"http://www.google.com"});
	console.log(r);
})();

cofy nodejs fs api:

'use strict';
var cofy = require('../');
var co = require('co');

var fs = require('fs');
cofy(fs);

//fs.exists callback function has no error. we call set `throwable` to false.
fs.$exists = cofy.object(fs.exists , false ,fs);	

co(function*(){
	var file = '/hello.txt';
	if(!(yield fs.$exists(file))){
		return;
	}
	var r = yield fs.$readFile(file,'utf8');
	console.log('fda' , r);
	//also you can use it in old way
	fs.readFile(file , 'utf8' , function(e,r){
		if(e){
			throw e;
		}
		console.log(r);
	});
})();

cofy API

class(constructor,[throwable],[methods],[prefix])

Enable a class or a object or a function to has co ability.

• constructor {function} - cofy target.the constructor of the class;
• throwable {bool} - if throwable is true the first argument of callback function arguments will be deemed as a exception.if throwable is false,no exception will be throwed ,all arguments will be returned. default is true.
• methods {array} - Array,if exists ,cofy will only cofy the methods in the target.
• prefix {string} - cofy will add function to the target(except target is function),the function name has a prefix. default is $.

object(object,[throwable],[methods],[prefix],[context])

• object {function} - cofy target.the constructor of the class;
• throwable {bool} - if throwable is true the first argument of callback function arguments will be deemed as a exception.if throwable is false,no exception will be throwed ,all arguments will be returned. default is true.
• context {object} - the function execute context.
• methods {array} - Array,if exists ,cofy will only cofy the methods in the target.
• prefix {string} - cofy will add function to the target(except target is function),the function name has a prefix. default is $.

fn(fn,[throwable],[context])

• fn {function} - cofy a function; function(args , cb) -> yeild function(args)
• throwable {bool} - if throwable is true the first argument of callback function arguments will be deemed as a exception.if throwable is false,no exception will be throwed ,all arguments will be returned. default is true.
• context {object} - the function execute context.