#Gin Web Framework
Gin is a web framework written in Golang. It features a martini-like API with much better performance, up to 40 times faster. If you need performance and good productivity, you will love Gin.
Check out the official web site
Start using it
Run:
go get github.com/gin-gonic/gin
Then import it in your Golang code:
import "github.com/gin-gonic/gin"
##API Examples
Create most basic PING/PONG HTTP endpoint
import "github.com/gin-gonic/gin"
func main() {
r := gin.Default()
r.GET("ping", func(c *gin.Context){
c.String("pong")
})
// Listen and server on 0.0.0.0:8080
r.Run(":80")
}
Using GET, POST, PUT, PATCH and DELETE
func main() {
// Creates a gin router + logger and recovery (crash-free) middlwares
r := gin.Default()
r.GET("/someGet", getting)
r.POST("/somePost", posting)
r.PUT("/somePut", putting)
r.DELETE("/someDelete", deleting)
r.PATCH("/somePATCH", patching)
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
Parameters in path
func main() {
r := gin.Default()
r.GET("/user/:name", func(c *gin.Context) {
name := c.Params.ByName("name")
message := "Hello "+name
c.String(200, message)
})
}
Grouping routes
func main() {
r := gin.Default()
// Simple group: v1
v1 := r.Group("/v1")
{
v1.POST("/login", loginEndpoint)
v1.POST("/submit", submitEndpoint)
v1.POST("/read", readEndpoint)
}
// Simple group: v1
v2 := r.Group("/v2")
{
v2.POST("/login", loginEndpoint)
v2.POST("/submit"", submitEndpoint)
v2.POST("/read"", readEndpoint)
}
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
Blank Gin without middlewares by default
Use
r := gin.New()
instead of
r := gin.Default()
Using middlewares
func main() {
// Creates a router without any middlware by default
r := gin.New()
// Global middlwares
r.Use(gin.Logger())
r.Use(gin.Recovery())
// Per route middlwares, you can add as many as you desire.
r.GET("/benchmark", MyBenchLogger(), benchEndpoint)
// Authorization group
// authorized := r.Group("/", AuthRequired())
// exactly the same than:
authorized := r.Group("/")
// per group middlwares! in this case we use the custom created
// AuthRequired() middlware just in the "authorized" group.
authorized.Use(AuthRequired())
{
authorized.Use.POST("/login", loginEndpoint)
authorized.Use.POST("/submit", submitEndpoint)
authorized.Use.POST("/read", readEndpoint)
// nested group
testing := authorized.Group("testing")
testing.GET("/analytics", analyticsEndpoint)
}
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
JSON parsing and validation
type LoginJSON struct {
User string `json:"user" binding:"required"`
Password string `json:"password" binding:"required"`
}
func main() {
r := gin.Default()
r.POST("/login", func(c *gin.Context) {
var json LoginJSON
// If EnsureBody returns false, it will write automatically the error
// in the HTTP stream and return a 400 error. If you want custom error
// handling you should use: c.ParseBody(interface{}) error
if c.EnsureBody(&json) {
if json.User=="manu" && json.Password=="123" {
c.JSON(200, gin.H{"status": "you are logged in"})
}else{
c.JSON(401, gin.H{"status": "unauthorized"})
}
}
})
}
XML, and JSON rendering
func main() {
r := gin.Default()
// gin.H is a shortcup for map[string]interface{}
r.GET("/someJSON", func(c *gin.Context) {
c.JSON(200, gin.H{"message": "hey", "status": 200})
})
r.GET("/moreJSON", func(c *gin.Context) {
// You also can use a struct
var msg struct {
Message string
Status int
}
msg.Message = "hey"
msg.Status = 200
c.JSON(200, msg.Status)
})
r.GET("/someXML", func(c *gin.Context) {
c.XML(200, gin.H{"message": "hey", "status": 200})
})
}
####HTML rendering
Using LoadHTMLTemplates()
func main() {
r := gin.Default()
r.LoadHTMLTemplates("templates/*")
r.GET("index", func(c *gin.Context) {
obj := gin.h{"title": "Main website"}
c.HTML(200, "templates/index.tmpl", obj)
})
}
You can also use your own html template render
import "html/template"
func main() {
r := gin.Default()
html := template.ParseFiles("file1", "file2")
r.HTMLTemplates = html
}
Custom Middlewares
func Logger() gin.HandlerFunc {
return func(c *gin.Context) {
t : time.Now()
// Set example variable
c.Set("example", "12345")
// before request
c.Next()
// after request
latency := time.Since(t)
log.Print(latency)
}
}
func main() {
r := gin.New()
r.Use(Logger())
r.GET("test", func(c *gin.Context){
example := r.Get("example").(string)
// it would print: "12345"
log.Println(example)
})
}
Custom HTTP configuration
Use http.ListenAndServe()
directly, like this:
func main() {
router := gin.Default()
http.ListenAndServe(":8080", router)
}
or
func main() {
router := gin.Default()
s := &http.Server{
Addr: ":8080",
Handler: router,
ReadTimeout: 10 * time.Second,
WriteTimeout: 10 * time.Second,
MaxHeaderBytes: 1 << 20,
}
s.ListenAndServe()
}