Loopback3: Comprehensive AccessType, Property and End-point

Access Type	Property	Verb	End point
READ	find	GET	/model-name-plural
	findById	GET	/model-name-plural/{id}
	exists	HEAD	/model-name-plural/{id}
	exists	READ	/model-name-plural/{id}/exists
	__get__relationName	GET	/model-name-plural/{id}/relationName
	__findById__relationName	GET	/model-name-plural/{id}/relationName/{fk}
	__count__relationName	GET	/model-name-plural/{id}/relationname
	createChangeStream	GET	/model-name-plural/change-stream
	createChangeStream	POST	/model-name-plural/change-stream
	count	GET	/model-name-plural/count
	findOne	GET	/model-name-plural/findOne
WRITE	upsert	PATCH	/model-name-plural
	upsert	PUT	/model-name-plural
	create	POST	/model-name-plural
	updateAttributes	PATCH	/model-name-plural/{id}
	updateAttributes	PUT	/model-name-plural/{id}
	deleteById	DELETE	/model-name-plural/{id}
	replaceById	POST	/model-name-plural/{id}/replace
	__create__relationName	POST	/model-name-plural/{id}/relationName
	__delete__relationName	DELETE	/model-name-plural/{id}/relationName
	__updateById__relationName	PUT	/model-name-plural/{id}/relationName/{fk}
	__destroyById__relationName	DELETE	/model-name-plural/{id}/relationName/{fk}
	replaceOrCreate	POST	/model-name-plural/replaceOrCreate
	updateAll	POST	/model-name-plural/update
	upsertWithWhere	POST	/model-name-plural/upsertWithWhere

Loopback & MongoDB

từ loopback muốn truy cập vào mongodb có pass thì phải tạo account từ database muốn truy cập vào
ví dụ

"accountDS": {
    "name": "accountDS",
    "connector": "mongodb",
    "host": "demo.strongloop.com",
    "port": 27017,
    "database": "demoDB",
    "username": "demoUser",
    "password": "L00pBack"
  }

thi tức là loopback muốn truy cập vào database tên là demoDB
vậy thì phải tạo user sau trên mongodb

//_id là demoDB.demoUser
use demoDB;
db.createUser({user:"demoUser",pwd:"L00pBack",roles:["readWrite","dbAdmin"]})

chứ không đuợc tạo user trên database admin như sau

//_id là admin.demoUser

use admin;

db.createUser({user:"demoUser",pwd:"L00pBack",roles:["readWrite","dbAdmin"]})

(tuy 2 user có cùng tên là demoUser nhưng vì đuợc tạo trên 2 database khác nhau nên chúng tồn tại song song đuợc)

-----------

Tuy nhiên, khi sử dụng mongo compass để truy cập vào DB thì lại phải tạo user trên database admin

(ví dụ: với 2 user đã tạo ở trên thì admin.demoUser mới có thể sử dụng trong mongo compass đuợc. demoDB.demoUser không thể dùng trong compass đuợc)_

Getting Started (Loopback 3)

Install

Assuming you have already installed Node...

Install the LoopBack CLI tool.

$ npm install -g loopback-cli

Create app

Create a "Hello World" LoopBack application.

$ lb
? What's the name of your application? hello-world
? Enter name of the directory to contain the project: hello-world

? Which version of LoopBack would you like to use? 3.x (Active Long Term Support)
? What kind of application do you have in mind? hello-world (A project containing a controller,
including a single vanilla Message and a single remote method)
...
I'm all done. Running npm install for you to install the required dependencies.
If this fails, try running the command yourself.
... 

Create models

$ lb model

---

The generator guides you through creating your model. Enter the values highlighted in green. To accept the default, just press Enter.

[?] Enter the model name: person
[?] Select the data-source to attach person to: db (memory)
[?] Select model`s base class (PersistedModel)
[?] Expose person via the REST API? Yes
[?] Custom plural form (used to build REST URL): people
[?] Common model or server only? common
Let's add some person properties now.

---

Define a firstname property for the person model

Enter an empty property name when done.
[?] Property name: firstname

---

Hit Enter to accept the default string type:

[?] Property type: (Use arrow keys)
❯ string
  number
  boolean
  object
  array
  date
  buffer
  geopoint
  any
  (other)

---

Make the property required.

[?] Required? (y/N) y

---

Repeat these steps for lastname property.

Press Enter when prompted for a property name to finish up and create the model.

Run the application

Run as you would any Node application.

$ node .
Browse your REST API at http://0.0.0.0:3000/explorer
Web server listening at: http://0.0.0.0:3000/

When you're ready to think about moving to production, give IBM API Connect a try. It enables you to easily deploy your LoopBack app to the cloud or on-premises. It has a built-in API gateway, and it has a visual editor for LoopBack apps!

Explore your REST API

Load http://0.0.0.0:3000/explorer to see the built-in API Explorer.

The API Explorer enables you to exercise all the generated API endpoints. There are create, read, update, and delete (CRUD) endpoints for the people model you just created.

For more information, see the Using the API Explorer in the documentation. You may also want to follow the Getting Started tutorial.

Getting started (Loopback4)

Have you installed Node.js?

Before you install LoopBack, make sure to download and install Node.js (version 8.9.x or higher), a JavaScript runtime.

Install Node.js

---

Install LoopBack 4 CLI

The LoopBack 4 CLI is a command-line interface that can scaffold a project or extension. The CLI provides the fastest way to get started with a LoopBack 4 project that adheres to best practices.

$ npm install -g @loopback/cli
                    

---

Create a new project

To create a new project, run the CLI as follows.

$ lb4 app
                    

---

Answer the prompts as follows.

[?] Project name: getting-started
[?] Project description: Getting started tutorial
[?] Project root directory: (getting-started)
[?] Application class name: StarterApplication
[?] Select project build settings: Enable tslint, Enable prettier, Enable mocha, Enable loopbackBuild
                    

---

Starting the project

The project comes with a "ping" route to test the project. Let's try it out by running the projects.

In a browser, visit http://127.0.0.1:3000/ping

$ cd getting-started
$ npm start
                    

---

Add your own controller

Now that we have a basic project created, it’s time to add our own controller. Let’s add a simple “Hello World” controller as follows.

 $ lb4 controller
[?] Controller class name: hello
[?] What kind of controller would you like to generate? Empty Controller
    create src/controllers/hello.controller.ts
    update src/controllers/index.ts
Controller Hello was now created in src/controllers/
                    

---

Paste the following contents into the file /src/controllers/hello.controller.ts.

import {get} from '@loopback/rest';
export class HelloController {
  @get('/hello')
  hello(): string {
    return 'Hello world!';
  }
}
                    

---

Test your application

Start the application using npm start.

Visit http://127.0.0.1:3000/hello to see Hello world!

Loopback

Có sự khác biệt lớn giua v3 và v4