#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.
##Gin is new, will it be supported?
Yes, Gin is an internal project of my upcoming startup. We developed it and we are going to continue using and improve it.
##Roadmap for v0.2
- Performance improments, reduce allocation and garbage collection overhead
- Fix bugs
- Ask our designer for a cool logo
- Add tons of unit tests and benchmarks
- Improve logging system
- Improve JSON/XML validation using bindings
- Improve XML support
- Improve documentation
- Add more cool middlewares, for example redis catching (this also helps developers to understand the framework)
- Continuous integration
Obviously, you need to have Git and Go! already installed to run Gin.
Run this in your terminal
go get github.com/gin-gonic/gin
Then import it in your Go! code:
import "github.com/gin-gonic/gin"
##API Examples
import "github.com/gin-gonic/gin"
func main() {
r := gin.Default()
r.GET("/ping", func(c *gin.Context){
c.String(200, "pong")
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
func main() {
// Creates a gin router + logger and recovery (crash-free) middlewares
r := gin.Default()
r.GET("/someGet", getting)
r.POST("/somePost", posting)
r.PUT("/somePut", putting)
r.DELETE("/someDelete", deleting)
r.PATCH("/somePatch", patching)
r.HEAD("/someHead", head)
r.OPTIONS("/someOptions", options)
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
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)
})
r.GET("/user/:name/:action", func(c *gin.Context) {
name := c.Params.ByName("name")
action := c.Params.ByName("action")
message := name + " is " + action
c.String(200, message)
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
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: v2
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")
}
Use
r := gin.New()
instead of
r := gin.Default()
func main() {
// Creates a router without any middleware by default
r := gin.New()
// Global middlewares
r.Use(gin.Logger())
r.Use(gin.Recovery())
// Per route middlewares, 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 middlewares! in this case we use the custom created
// AuthRequired() middleware just in the "authorized" group.
authorized.Use(AuthRequired())
{
authorized.POST("/login", loginEndpoint)
authorized.POST("/submit", submitEndpoint)
authorized.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")
}
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"})
}
}
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
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 {
Name string `json:"user"`
Message string
Number int
}
msg.Name = "Lena"
msg.Message = "hey"
msg.Number = 123
// Note that msg.Name becomes "user" in the JSON
// Will output : {"user": "Lena", "Message": "hey", "Number": 123}
c.JSON(200, msg)
})
r.GET("/someXML", func(c *gin.Context) {
c.XML(200, gin.H{"message": "hey", "status": 200})
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
####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, "index.tmpl", obj)
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
You can also use your own html template render
import "html/template"
func main() {
r := gin.Default()
html := template.Must(template.ParseFiles("file1", "file2"))
r.HTMLTemplates = html
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
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)
// access the status we are sending
status := c.Writer.Status()
log.Println(status)
}
}
func main() {
r := gin.New()
r.Use(Logger())
r.GET("/test", func(c *gin.Context){
example := c.MustGet("example").(string)
// it would print: "12345"
log.Println(example)
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
// similate some private data
var secrets = gin.H{
"foo": gin.H{"email": "[email protected]", "phone": "123433"},
"austin": gin.H{"email": "[email protected]", "phone": "666"},
"lena": gin.H{"email": "[email protected]", "phone": "523443"},
}
func main() {
r := gin.Default()
// Group using gin.BasicAuth() middleware
// gin.Accounts is a shortcut for map[string]string
authorized := r.Group("/admin", gin.BasicAuth(gin.Accounts{
"foo": "bar",
"austin": "1234",
"lena": "hello2",
"manu": "4321",
}))
// /admin/secrets endpoint
// hit "localhost:8080/admin/secrets
authorized.GET("/secrets", func(c *gin.Context) {
// get user, it was setted by the BasicAuth middleware
user := c.Get(gin.AuthUserKey).(string)
if secret, ok := secrets[user]; ok {
c.JSON(200, gin.H{"user": user, "secret": secret})
} else {
c.JSON(200, gin.H{"user": user, "secret": "NO SECRET :("})
}
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
When starting inside a middleware or handler, you SHOULD NOT use the original context inside it, you have to use a read-only copy.
func main() {
r := gin.Default()
r.GET("/long_async", func(c *gin.Context) {
// create copy to be used inside the goroutine
c_cp := c.Copy()
go func() {
// simulate a long task with time.Sleep(). 5 seconds
time.Sleep(5 * time.Second)
// note than you are using the copied context "c_cp", IMPORTANT
log.Println("Done! in path " + c_cp.Req.URL.Path)
}()
})
r.GET("/long_sync", func(c *gin.Context) {
// simulate a long task with time.Sleep(). 5 seconds
time.Sleep(5 * time.Second)
// since we are NOT using a goroutine, we do not have to copy the context
log.Println("Done! in path " + c.Req.URL.Path)
})
// Listen and server on 0.0.0.0:8080
r.Run(":8080")
}
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()
}