🍸

package main

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

func main() {
    r := gin.Default()
    
    r.GET("/", func(c *gin.Context) {
        c.JSON(200, gin.H{"message": "Hello World"})
    })
    
    r.Run(":8080")
}

// Path parameter
r.GET("/user/:id", func(c *gin.Context) {
    id := c.Param("id")
    c.JSON(200, gin.H{"id": id})
})

// Query parameter
r.GET("/search", func(c *gin.Context) {
    q := c.DefaultQuery("q", "")
    page := c.Query("page")
    c.JSON(200, gin.H{"q": q, "page": page})
})

r.GET("/resource", getHandler)
r.POST("/resource", createHandler)
r.PUT("/resource/:id", updateHandler)
r.PATCH("/resource/:id", patchHandler)
r.DELETE("/resource/:id", deleteHandler)
r.HEAD("/resource", headHandler)
r.OPTIONS("/resource", optionsHandler)

// Any method
r.Any("/any", anyHandler)

// Custom methods
r.Handle("CUSTOM", "/custom", handler)

api := r.Group("/api")
{
    api.GET("/users", getUsers)
    api.POST("/users", createUser)
    
    v1 := api.Group("/v1")
    {
        v1.GET("/items", getItems)
    }
}

// With middleware
authorized := r.Group("/admin")
authorized.Use(AuthMiddleware())
{
    authorized.GET("/dashboard", dashboard)
}

type CreateUser struct {
    Name  string `json:"name" binding:"required"`
    Email string `json:"email" binding:"required,email"`
    Age   int    `json:"age" binding:"gte=0,lte=120"`
}

func createUser(c *gin.Context) {
    var user CreateUser
    if err := c.ShouldBindJSON(&user); err != nil {
        c.JSON(400, gin.H{"error": err.Error()})
        return
    }
    c.JSON(200, user)
}

type LoginForm struct {
    Username string `form:"username" binding:"required"`
    Password string `form:"password" binding:"required"`
}

func login(c *gin.Context) {
    var form LoginForm
    if err := c.ShouldBind(&form); err != nil {
        c.JSON(400, gin.H{"error": err.Error()})
        return
    }
    // Process login
}

// File upload
func upload(c *gin.Context) {
    file, _ := c.FormFile("file")
    c.SaveUploadedFile(file, "uploads/"+file.Filename)
}

// JSON
c.JSON(200, gin.H{"status": "ok"})
c.JSON(200, user) // struct

// IndentedJSON (pretty)
c.IndentedJSON(200, data)

// SecureJSON (prevents JSON hijacking)
c.SecureJSON(200, []string{"a", "b"})

// JSONP
c.JSONP(200, gin.H{"data": "value"})

// String
c.String(200, "Hello %s", name)

// HTML
c.HTML(200, "index.html", gin.H{"title": "Home"})

// XML
c.XML(200, gin.H{"message": "ok"})

// YAML
c.YAML(200, gin.H{"message": "ok"})

// File
c.File("./files/doc.pdf")
c.FileAttachment("./files/doc.pdf", "document.pdf")

// Redirect
c.Redirect(301, "/new-path")

func Logger() gin.HandlerFunc {
    return func(c *gin.Context) {
        t := time.Now()
        
        // Before request
        c.Set("start", t)
        
        c.Next() // Process request
        
        // After request
        latency := time.Since(t)
        log.Printf("Latency: %v", latency)
    }
}

// Use globally
r.Use(Logger())

// Use on route
r.GET("/", Logger(), handler)

// Logger & Recovery (included in Default())
r := gin.New()
r.Use(gin.Logger())
r.Use(gin.Recovery())

// Basic Auth
authorized := r.Group("/admin")
authorized.Use(gin.BasicAuth(gin.Accounts{
    "admin": "secret",
}))

// CORS (use gin-contrib/cors)
import "github.com/gin-contrib/cors"

r.Use(cors.New(cors.Config{
    AllowOrigins: []string{"*"},
    AllowMethods: []string{"GET", "POST"},
}))