go 49 lines · 6 steps

How route groups nest in Gin

Gin's router groups share a path prefix and middleware, letting you compose versioned, authenticated API trees from small pieces.

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Gin Intermediate routing middleware api versioning composition http
1package main
2 
3import (
4 "net/http"
5 
6 "github.com/gin-gonic/gin"
7)
8 
9func RegisterRoutes(r *gin.Engine, h *Handler) {
10 api := r.Group("/api")
11 
12 v1 := api.Group("/v1")
13 {
14 v1.Use(AuthRequired())
15 
16 users := v1.Group("/users")
17 {
18 users.GET("", h.ListUsers)
19 users.POST("", h.CreateUser)
20 users.GET("/:id", h.GetUser)
21 users.PATCH("/:id", h.UpdateUser)
22 users.DELETE("/:id", h.DeleteUser)
23 }
24 
25 posts := v1.Group("/posts")
26 {
27 posts.GET("", h.ListPosts)
28 posts.POST("", h.CreatePost)
29 posts.GET("/:id/comments", h.ListComments)
30 }
31 }
32 
33 v2 := api.Group("/v2")
34 {
35 v2.Use(AuthRequired(), RateLimit(100))
36 v2.GET("/users", h.ListUsersV2)
37 v2.POST("/users", h.CreateUserV2)
38 }
39}
40 
41func AuthRequired() gin.HandlerFunc {
42 return func(c *gin.Context) {
43 if c.GetHeader("Authorization") == "" {
44 c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{"error": "missing token"})
45 return
46 }
47 c.Next()
48 }
49}
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Route groups let a shared prefix and middleware apply to every route registered under them.
  2. 2Nesting groups keeps versioned APIs organized and lets each tier layer on its own middleware.
  3. 3Middleware is just a handler that either aborts the request or calls Next to continue the chain.

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