Installation
To install Gin package, you need to install Go and set your Go workspace first.
- The first need Go installed (version 1.12+ is required), then you can use the below Go command to install Gin.
$ go get -u github.com/gin-gonic/gin
- Import it in your code:
import "github.com/gin-gonic/gin"
- (Optional) Import
net/http. This is required for example if using constants such ashttp.StatusOK.
import "net/http"
Quick start
assume the following codes in example.go file
$ cat example.go
package main
import "github.com/gin-gonic/gin"
func main() {
r := gin.Default()r.GET("/ping", func(c *gin.Context) { c.JSON(200, gin.H{ "message": "pong", })})r.Run() // listen and serve on 0.0.0.0:8080 (for windows "localhost:8080")}
# run example.go and visit 0.0.0.0:8080/ping (for windows "localhost:8080/ping") on browser$ go run example.goUsing GET, POST, PUT, PATCH, DELETE and OPTIONS
func main() {
// Creates a gin router with default middleware:// logger and recovery (crash-free) middlewarerouter := gin.Default()router.GET("/someGet", getting)router.POST("/somePost", posting)router.PUT("/somePut", putting)router.DELETE("/someDelete", deleting)router.PATCH("/somePatch", patching)router.HEAD("/someHead", head)router.OPTIONS("/someOptions", options)// By default it serves on :8080 unless a// PORT environment variable was defined.router.Run()// router.Run(":3000") for a hard coded port}
Parameters in path
func main() {
router := gin.Default()// This handler will match /user/john but will not match /user/ or /userrouter.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 definitionrouter.POST("/user/:name/*action", func(c *gin.Context) { c.FullPath() == "/user/:name/*action" // true})router.Run(":8080")}
Querystring parameters
func main() {
router := gin.Default()// Query string parameters are parsed using the existing underlying request object.// The request responds to a url matching: /welcome?firstname=Jane&lastname=Doerouter.GET("/welcome", func(c *gin.Context) { firstname := c.DefaultQuery("firstname", "Guest") lastname := c.Query("lastname") // shortcut for c.Request.URL.Query().Get("lastname") c.String(http.StatusOK, "Hello %s %s", firstname, lastname)})router.Run(":8080")}
Multipart/Urlencoded Form
func main() {
router := gin.Default()router.POST("/form_post", func(c *gin.Context) { message := c.PostForm("message") nick := c.DefaultPostForm("nick", "anonymous") c.JSON(200, gin.H{ "status": "posted", "message": message, "nick": nick, })})router.Run(":8080")}
Another example: query + post form
POST /post?id=1234&page=1 HTTP/1.1Content-Type: application/x-www-form-urlencodedname=manu&message=this_is_great func main() {
router := gin.Default()router.POST("/post", func(c *gin.Context) { id := c.Query("id") page := c.DefaultQuery("page", "0") name := c.PostForm("name") message := c.PostForm("message") fmt.Printf("id: %s; page: %s; name: %s; message: %s", id, page, name, message)})router.Run(":8080")}
id: 1234; page: 1; name: manu; message: this_is_great Map as querystring or postform parameters
POST /post?ids[a]=1234&ids[b]=hello HTTP/1.1Content-Type: application/x-www-form-urlencodednames[first]=thinkerou&names[second]=tianou func main() {
router := gin.Default()router.POST("/post", func(c *gin.Context) { ids := c.QueryMap("ids") names := c.PostFormMap("names") fmt.Printf("ids: %v; names: %v", ids, names)})router.Run(":8080")}
ids: map[b:hello a:1234]; names: map[second:tianou first:thinkerou]