Gin是web框架，可以用于创建基本的RESTful服务API

设计API

获取album列表

GET /albums

创建album

POST /albums

获取album详情

GET /albums/:id

项目开发

创建项目并初始化

mkdir web-service-gin
cd web-service-gin
go mod init example/web-service-gin

准备

创建album数组数据，这里定义album的结构体类型

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

// album represents data about a record album.
type album struct {
    ID     string  `json:"id"`
    Title  string  `json:"title"`
    Artist string  `json:"artist"`
    Price  float64 `json:"price"`
}

// albums slice to seed record album data.
var albums = []album{
    {ID: "1", Title: "Blue Train", Artist: "John Coltrane", Price: 56.99},
    {ID: "2", Title: "Jeru", Artist: "Gerry Mulligan", Price: 17.99},
    {ID: "3", Title: "Sarah Vaughan and Clifford Brown", Artist: "Sarah Vaughan", Price: 39.99},
}

handler

handler是用于处理http请求的逻辑块

获取全部item

// getAlbums responds with the list of all albums as JSON.
func getAlbums(c *gin.Context) {
	c.IndentedJSON(http.StatusOK, albums)
}

func main() {
	router := gin.Default()
	router.GET("/albums", getAlbums)

	router.Run("localhost:8080")
}

获取依赖

go get .

运行项目

go run .

测试API

curl http://localhost:8080/albums

创建item

// postAlbums adds an album from JSON received in the request body.
func postAlbums(c *gin.Context) {
	var newAlbum album

	// Call BindJSON to bind the received JSON to
	// newAlbum.
	if err := c.BindJSON(&newAlbum); err != nil {
		return
	}

	// Add the new album to the slice.
	albums = append(albums, newAlbum)
	c.IndentedJSON(http.StatusCreated, newAlbum)
}

func main() {
	router := gin.Default()
	router.GET("/albums", getAlbums)
	router.POST("/albums", postAlbums)

	router.Run("localhost:8080")
}

运行项目，测试API，新增item

 curl http://localhost:8080/albums \
    --include \
    --header "Content-Type: application/json" \
    --request "POST" \
    --data '{"id": "4","title": "The Modern Sound of Betty Carter","artist": "Betty Carter","price": 49.99}'

获取全部Item

curl http://localhost:8080/albums \
    --header "Content-Type: application/json" \
    --request "GET"

获取Item详情

// getAlbumByID locates the album whose ID value matches the id
// parameter sent by the client, then returns that album as a response.
func getAlbumByID(c *gin.Context) {
	id := c.Param("id")

	// Loop over the list of albums, looking for
	// an album whose ID value matches the parameter.
	for _, a := range albums {
		if a.ID == id {
			c.IndentedJSON(http.StatusOK, a)
			return
		}
	}
	c.IndentedJSON(http.StatusNotFound, gin.H{"message": "album not found"})
}

func main() {
	router := gin.Default()
	router.GET("/albums", getAlbums)
	router.GET("/albums/:id", getAlbumByID)
	router.POST("/albums", postAlbums)

	router.Run("localhost:8080")
}

运行项目并测试API

curl http://localhost:8080/albums/2

当前代码修改并不能热加载。