Gin の使い方

参考ページ
Quick start

インストール

mkdir gin_work && cd gin_work
go mod init gin_work
go get -u github.com/gin-gonic/gin

サンプル

example.go

package main

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

func main() {
	rr := gin.Default()
	rr.GET("/ping", func(cc *gin.Context) {
		cc.JSON(200, gin.H{
			"message": "pong",
		})
	})
	rr.Run()
}

サーバーの実行

go run example.go

http://localhost:8080/ping にアクセスする

curl http://localhost:8080/ping

http :8080/ping

Parameter を使うサンプル

parameters.go

package main

import "github.com/gin-gonic/gin"
import "net/http"

func main() {
	router := gin.Default()

	// This handler will match /user/john but will not match /user/ or /user
	router.GET("/user/:name", func(c *gin.Context) {
		name := c.Param("name")
		c.String(http.StatusOK, "Hello %s", name)
	})

	// However, this one will match /user/john/ and also /user/john/send
	// If no other routers match /user/john, it will redirect to /user/john/
	router.GET("/user/:name/*action", func(c *gin.Context) {
		name := c.Param("name")
		action := c.Param("action")
		message := name + " is " + action
		c.String(http.StatusOK, message)
	})

	// For each matched request Context will hold the route definition
	router.POST("/user/:name/*action", func(c *gin.Context) {
//		c.FullPath() == "/user/:name/*action" // true
	})

	router.Run(":8080")
}

サーバーの実行

go run parameters.go

クライアントからアクセス

curl http://localhost:8080/user/john

curl http://localhost:8080/user/john/send

$ http :8080/user/john
HTTP/1.1 200 OK
Content-Length: 10
Content-Type: text/plain; charset=utf-8
Date: Tue, 23 May 2023 06:33:17 GMT

Hello john

$ http :8080/user/john/send
HTTP/1.1 200 OK
Content-Length: 13
Content-Type: text/plain; charset=utf-8
Date: Tue, 23 May 2023 06:33:07 GMT

john is /send

確認したバージョン

$ go version
go version go1.20.3 linux/amd64