cofy

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
`



$3

Some examples

use cofy in redis.
`javascript
'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.
`javascript
'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.
`javascript
'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:
`js
'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

$3

Enalbe 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 $.

$3

- 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 $.

$3

- 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.