1. Rest and RestFul

REST (English: Representational State Transfer, referred to as REST), Representational State Transfer, refers to a set of architectural principles.

Restful: a web service or web application that complies with the rest principle.

2. Six elements of API design

Resource path (URI), HTTP verb (Method), query string, status code, error, result

1) Resource path URI

Resources: all data saved in the server (such as music / video / articles / personal information...) are server-side resources (resources in the project usually refer to a piece of data in the data table)

URI (Uniform Resource Identifier): uniform resource identifier, including URL and URN.

URL (uniform resource locator): Uniform Resource Locator

URN (Uniform Resource Name): Uniform Resource Name

In HTTP protocol, URI is composed as follows

Schema://host[:port]/path[?query-string]

Schema: the protocol type used, such as http/https/ftp

Host: host domain name or IP

Port: port number (optional)

path: path

Query string: query parameters (optional)

example:

http://www.tpshop.com/users

https://www.tpshop.com:8080/users?id=100

2) HTTP verb (request mode)

For resources, there are generally four operations, curd (add / delete / modify / query)

GET: GET the resource (one or more) from the server

POST: create a new resource on the server

PUT: when the server updates the resource, the server returns the complete attribute

DELETE: DELETE resource from server

3) Filter information

It is also commonly referred to as a request parameter or query string.

4) Response status code

The information returned by the server is used to tell the client the operation result.

Common status codes:

Status code	meaning	explain
200	OK	The operation is successful and the data is returned
201	CREATED	New successfully
204	NO CONTENT	Delete succeeded
400	BAD REQUEST	Request syntax error
403	Forbidden	Request resources without permission
404	NOT FOUND	The requested resource was not found

GET

200(OK) - Indicates that it has been issued in the response 
204((no content) - Resource empty representation 
301(Moved Permanently) - Resource URI Updated 
303(See Other) - Others (e.g., load balancing) 
304(not modified)- Resource not changed (CACHE) 
400 (bad request)- Refers to a bad request (e.g., parameter error) 
404 (not found)- Resource does not exist 
406 (not acceptable)- The server does not support the required representation 
500 (internal server error)- General error response 
503 (Service Unavailable)- The server is currently unable to process the request

POST

200(OK)- If an existing resource has been changed 
201(created)- If a new resource is created 
202(accepted)- Processing request accepted but not completed (asynchronous processing) 
301(Moved Permanently)- Resource URI Updated 
303(See Other)- Others (e.g., load balancing) 
400(bad request)- Bad request 
404 (not found)- Resource does not exist 
406 (not acceptable)- The server does not support the required representation 
409 (conflict)- Generic conflict 
412 (Precondition Failed)- Precondition failure (such as conflict when performing condition update) 
415 (unsupported media type)- The received representation is not supported 
500 (internal server error)- General error response 
503 (Service Unavailable)- The service is currently unable to process the request

PUT

200 (OK)- If the resource already exists, it will be changed 
201 (created)- If a new resource is created 
301(Moved Permanently)- Resource URI Changed 
303 (See Other)- Others (e.g., load balancing) 
400 (bad request)- Bad request 
404 (not found)- Resource does not exist 
406 (not acceptable)- The server does not support the required representation 
409 (conflict)- Generic conflict 
412 (Precondition Failed)- Precondition failure (such as conflict when performing condition update) 
415 (unsupported media type)- The received representation is not supported 
500 (internal server error)- General error response 
503 (Service Unavailable)- The service is currently unable to process the request

DELETE

200 (OK)- The resource has been deleted 
301 (Moved Permanently)- Resource URI Changed 
303 (See Other)- Others, such as load balancing 
400 (bad request)- Bad request 
404 (not found)- Resource does not exist 
409 (conflict)- Generic conflict 
500 (internal server error)- General error response 
503 (Service Unavailable)- The server is currently unable to process the request

5) Error message

If the status code is 4xx or 5xx, you need to tell the client the corresponding error message Usually returned in Json format:

{

"error": ""Error message",

}

6) Return results

For different operations, the results returned by the service should meet such specifications

GET /collections - returns a list of resources (array)

GET /collections/:id - returns a single resource eg. /collections/1

POST /collections - returns the newly generated resource

PUT /collections/:id - returns the complete attribute of the resource

DELETE /collections/:id - return 204 status code + empty document

In actual development, the status code, error information and return data are usually put into the return result.

such as

{"code":200, 'msg':'success', "data":{"id":1,"goods_name":"tp"}}

3. RestFul interface design style

Resource routing in TP framework

Manual - Routing - resource routing, manual - controller - resource controller

① Create api module

php think build --module api

② Create news controller

php think make:controller api/News

③ Set route (application/route.php)

\think\Route::resource('news','api/news');

It is equivalent to setting the following routes respectively:

\think\Route::get('news','api/news/index');
\think\Route::get('news/create','api/news/create');
\think\Route::post('news','api/news/save');
\think\Route::get('news/:id','api/news/read');
\think\Route::get('news/:id/edit','api/news/edit');
\think\Route::put('news/:id','api/news/update');
\think\Route::delete('news/:id','api/news/delete');

After setting, 7 routing rules will be registered automatically, as follows:

identification	Request type	Generate routing rules	Corresponding operation method (default)
index	GET	news	index
create	GET	news/create	create
save	POST	news	save
read	GET	news/:id	read
edit	GET	news/:id/edit	edit
update	PUT	news/:id	update
delete	DELETE	news/:id	delete

④ Modify the News controller to return json format data

<?php

namespace app\api\controller;

use think\Controller;
use think\Request;

class News extends Controller
{
    /**
     * Show resource list
     *
     * @return \think\Response
     */
    public function index()
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'index']);
    }

    /**
     * The create resource form page is displayed
     *
     * @return \think\Response
     */
    public function create()
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'create']);
    }

    /**
     * Save the new resource
     *
     * @param  \think\Request  $request
     * @return \think\Response
     */
    public function save(Request $request)
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'save']);
    }

    /**
     * Displays the specified resource
     *
     * @param  int  $id
     * @return \think\Response
     */
    public function read($id)
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'read']);
    }

    /**
     * The edit resource form page is displayed
     *
     * @param  int  $id
     * @return \think\Response
     */
    public function edit($id)
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'edit']);
    }

    /**
     * Save updated resources
     *
     * @param  \think\Request  $request
     * @param  int  $id
     * @return \think\Response
     */
    public function update(Request $request, $id)
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'update']);
    }

    /**
     * Delete the specified resource
     *
     * @param  int  $id
     * @return \think\Response
     */
    public function delete($id)
    {
        return json(['code' => 200, 'msg' => 'success', 'data'=>'delete']);
    }
}

Access the following seven addresses through postman:

Request mode     Request address
get            http://www.tpshop.com/news
get            http://www.tpshop.com/news/create
post        http://www.tpshop.com/news
get            http://www.tpshop.com/news/33
get            http://www.tpshop.com/news/33/edit
put            http://www.tpshop.com/news/33
delete        http://www.tpshop.com/news/33

4. ajax request restful interface

In the public directory, create the test file API html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>ajax request restful Interface</title>
    <script src="/static/admin/js/jquery-1.8.1.min.js"></script>
</head>
<body>
<input type="button" id="index" value="index">
<input type="button" id="create" value="create">
<input type="button" id="save" value="save">
<input type="button" id="read" value="read">
<input type="button" id="edit" value="edit">
<input type="button" id="update" value="update">
<input type="button" id="delete" value="delete">
<script>
    $(function(){
        $('#index').click(function(){
            $.ajax({
                "url":"/news",
                "type":"get",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#create').click(function(){
            $.ajax({
                "url":"/news/create",
                "type":"get",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#save').click(function(){
            $.ajax({
                "url":"/news",
                "type":"post",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#read').click(function(){
            $.ajax({
                "url":"/news/33",
                "type":"get",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#edit').click(function(){
            $.ajax({
                "url":"/news/33/edit",
                "type":"get",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#update').click(function(){
            $.ajax({
                "url":"/news/33",
                "type":"put",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
        $('#delete').click(function(){
            $.ajax({
                "url":"/news/33",
                "type":"delete",
                "data":"",
                "dataType":"json",
                "success":function(res){
                    console.log(res);
                }
            });
        });
    });
</script>
</body>
</html>