node-lego

Lego -- A node web modules framework

In web development, a web page is usually separated to lots of modules , head , article , footer , side ads...

And each module has individual data from db or service.

We fetch all these data and then render the template .

With Lego we made this easier.

Install

npm install node-lego --save

Usage

In your request handler :

var User = require("./user");
var OrderList = require("./orderlist");
var Profile = require("./profile");
var Lego = require("node-lego");
    
app.get("/index" , function(req , res){
    new Lego().start({
        userId: req.query.id
    })
    .pipe(User)
    .pipe(OrderList,Profile)
    .done(function(data){
        //data is something like 
        {
            userId:123,
            User:{
                name:'mangix',
                id:123,
                email:''
            },
            UserView:'<div>Hello mangix</div>',//rendered html 
            OrderList:[],
            OrderListView:'',
            Proflie:{},
            ProfileView:''
        }
            
        //use this data as you want
        
        //render the index.jade template
        res.render("index", data);
            
        //or return as json
        res.send(data);
    });
});

In module user.js:

var Brick = require("node-lego").Brick;
module.exports = Brick.create("User",function(params,finish){
    var userId = params.userId;
    getUser(userId,function(err , user){
        if(err){
            finish(Brick.FAIL);
        }else{
            finish(Brick.SUCCESS , user);
        }
    });
        
},"/index/user.jade");
    
 

In module orderlist.js

 
var Brick = require("node-lego").Brick;
module.exports=Brick.create("OrderList",function(params,finish){
    var user = params.User;
    if(!user){
        finish(Brick.FAIL);
    }else{
        getOrderList(user,function(err, list){
            if(err){
                finish(Brick.FAIL);
            }else{
                finish(Brick.SUCCESS, list);
            }
        });
    }
        
},"/index/orderlist.jade");
    
 

In profile.js , do something same as orderlist;

In index.jade

div #{User.name}
    
.orderlist !{OrderListView}
    
.profile !{PrifileView}		
 

API

Lego.setting

global config with a get and set function. Config list:

• view engine , default 'jade' , same as express , any template engin supported by consolidate is supported.
• views , default 'views' , root path of the template files , same as express
• debug , default 'process.NODE_EVN == "development" ' , debug mode , if true , view render error stack will set to the view property of the final data.

use Lego.setting.get and Lego.setting.set to get and set this config.

example:

var Lego = require("node-lego");
var path = require("path");
Lego.setting.set("views" , path.join(__dirname,"views"));
Lego.setting.set("view engine","jade");

Lego.Brick

Brick.create(name , handler);

• name {String} name of the module . An attribute with this name will set to the final data .
• handler {Function} handle function , params and finishCallback will be parsed in. Call this callback function with status and data.
• viewPath {String} optional, template file path, joined to setting.get("views"). if this argument provided , the template will be auto rendered when finish(Brick.SUCCESS ,data) called and a property Brick.Name+'View' will set to the final data with value as rendered html String.

example: define a module

var myBrick = Brick.create("User", function(params , finish){
    //call finish with `Brick.SUCCESS` or `Brick.FAIL`
    finish(Brick.SUCCESS , {
    	userId:123,
    	name:"mangix",
    	email:"[e-mail]"
    });
    
} , 'path/to/the/view.jade');
 

in view.jade

.userinfo
    a.name(href='/user/#{id}') #{name}
    .email #{email}
    

if this brick finish with Brick.SUCCESS , this view will be rendered with the data. and the final data in .done will get this properties.

 
User:{
    userId:123,
    	name:"mangix",
    	email:"[e-mail]"
},
UserView:'<div class="userinfo"><a href="/user/123">mangix</a><div class="email">[e-mail]</div></div>'
 
 

Brick.SUCCESS

in handler , call finish callback with Brick.SUCCESS when data fetching is success;

Brick.FAIL

in handler , call finish callback with Brick.FAIL when an error occurs , and the data will be set to null,template will not be rendered.

Brick.TIMEOUT

when an timeout option passed to Lego , if Brick handle timeout , finish will be called with TIMEOUT automatic. data will be null.

Lego

constructor Lego(options)

• options {Object}

 
{
    timeout:0 , //brick timeout time  ,default 0 , not control
}
 

lego.start(params)

• params {Object} initial data

start the module system with some initial data. Each Brick will get this data in handler.

new Lego().start({
    userId:1
});

lego.pipe(brick1,brick2....)

• brick Brick created by Brick.create()

execute each brick in the same time , and merge the data together. pipe could be called many times. pipes are serial and in each pipe bricks are in parallel. data will be merged and passed to the next.

example:

new Lego().start({
    id:1
})
 
//preBrick1 and preBrick2 will be executed at the same time
.pipe(preBrick1,preBrick2)
 
//nextBrick1 and nextBrick2 will be executed at the same time when preBricks are all finished
//and data finished by preBrick1 and preBrick2 will passed to nextBrick1 and nextBrick2
.pipe(nextBrick1,nextBrick2)
 
.done(function(data){
    //data will contains
    {
        id:1,   //data from start
        preBrick1: {},
        preBrick2: {},
        nextBrick1:{},
        nextBrick2:{}
    }
})

lego.top(brick,property,toProperty)

when Brick finish with Brick.SUCCESS and data , data will merge as follow:

{
    Brick1Name:data,
    Brick2Name:data
}

sometimes it's not convenient for the next Brick or template. You can use this method to convert the inside property to the top level.

• brick Brick create by Brick.create()
• property src property
• toProperty target property

example:

//in your user brick handle , you finish
finish(Brick.SUCCESS , {
    userInfo:{
        id:123,
        name:'xxx'
    }
});
 
//you have to use this data by data.User.userInfo.id , in the OrderBrick you have to :
Brick.create("orderBrick" , function(params , finish){
 
    //It's not a good idea to use params like this. 
    //It makes the OrderBrick to depend on the UserBrick,
    //but actually it's only depend on `userId`
    var userId = params.User.userInfo.id;
});
 
//with this api , after pipe UserBrick , call the `top` api to transfer userId to the top level.
new Lego().pipe(UserBrick).top(UserBrick,'userInfo.id','userId').pipe(OrderBrick);
 
//now in OrderBrick 
var userId = params.userId;
 
//you can also use OrderBrick in the first pipe,
//because it's not depend on params.User.userInfo.id
new Lego().start({
    userId:123
}).pipe(OrderBrick).done();
 

lego.done(callback)

• callback , callback function with data

when all pipes are finish , this callback will be called with the merged data

new Lego().start({
    id:1
}).pipe(brick1,brick2).done(function(data){
    //data is :{
        id:1,
        brick1Name:brick1Data,
        brick1NameView:'',
        brick2Name:brick2Data
        brick2NameView:''
    }
    // render template 
    res.render("template" , data);
    //or send json
    res.send(data);
    //or do anything you want
});