From 563bde429e91c495b9be36c6be013e9b6fc333ba Mon Sep 17 00:00:00 2001
From: Dumindu Madunuwan <dumindu.madunuwan@gmail.com>
Date: Mon, 24 Aug 2026 14:16:38 +0800
Subject: [PATCH] CORS

---
 .env                 |  4 ++++
 app/router/router.go | 16 +++++++++++++++-
 cmd/app/main.go      |  4 ++--
 config/config.go     |  7 +++++++
 go.mod               |  1 +
 go.sum               |  2 ++
 6 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/.env b/.env
index 4a32095..fcadf39 100644
--- a/.env
+++ b/.env
@@ -6,6 +6,10 @@ SERVER_TIMEOUT_WRITE=5s
 SERVER_TIMEOUT_IDLE=5s
 SERVER_DEBUG=true
 
+CORS_ALLOWED_ORIGINS="http://localhost:8080,http://127.0.0.1:8080"
+CORS_ALLOWED_HEADERS="Accept,Authorization,Content-Type,X-CSRF-Token"
+CORS_MAX_AGE=300
+
 DB_HOST=db
 DB_PORT=5432
 DB_USER=myapp_user
diff --git a/app/router/router.go b/app/router/router.go
index a0108a3..f180921 100644
--- a/app/router/router.go
+++ b/app/router/router.go
@@ -2,29 +2,43 @@ package router
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/cors"
 	"github.com/go-playground/validator/v10"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/hlog"
 	"gorm.io/gorm"
 
 	"myapp/app/book"
+	"myapp/config"
 	m "myapp/pkg/middleware"
 	mrl "myapp/pkg/middleware/requestlog"
 )
 
-func New(l *zerolog.Logger, v *validator.Validate, db *gorm.DB) *chi.Mux {
+func New(c *config.ConfCORS, l *zerolog.Logger, v *validator.Validate, db *gorm.DB) *chi.Mux {
 	r := chi.NewRouter()
 	r.Get("/livez", func(w http.ResponseWriter, _ *http.Request) {
 		w.Write([]byte("."))
 	})
 
+	cors := cors.New(cors.Options{
+		AllowedOrigins:   strings.Split(c.AllowedOrigins, ","),
+		AllowedMethods:   []string{http.MethodGet, http.MethodPost, http.MethodPut, http.MethodDelete, http.MethodOptions},
+		AllowedHeaders:   strings.Split(c.AllowedHeaders, ","),
+		AllowCredentials: true,
+		ExposedHeaders:   []string{""},
+		MaxAge:           c.MaxAge,
+	})
+
 	r.Route("/v1", func(r chi.Router) {
+		r.Use(cors.Handler)
 		r.Use(hlog.NewHandler(*l))
 		r.Use(hlog.RequestIDHandler("request_id", "X-Request-ID"))
 		r.Use(mrl.NewHandler)
 		r.Use(m.ContentTypeJSON)
+
 		r.Route("/books", book.New(v, db).Register)
 	})
 
diff --git a/cmd/app/main.go b/cmd/app/main.go
index 7ca4424..278fa9c 100644
--- a/cmd/app/main.go
+++ b/cmd/app/main.go
@@ -62,11 +62,11 @@ func main() {
 		return
 	}
 
-	r := router.New(&l, v, db)
+	mux := router.New(&c.CORS, &l, v, db)
 
 	s := &http.Server{
 		Addr:         fmt.Sprintf(":%d", c.Server.Port),
-		Handler:      r,
+		Handler:      mux,
 		ReadTimeout:  c.Server.TimeoutRead,
 		WriteTimeout: c.Server.TimeoutWrite,
 		IdleTimeout:  c.Server.TimeoutIdle,
diff --git a/config/config.go b/config/config.go
index 737efc3..caa2a5e 100644
--- a/config/config.go
+++ b/config/config.go
@@ -10,6 +10,7 @@ import (
 type Conf struct {
 	TZ     string `env:"TZ,required"`
 	Server ConfServer
+	CORS   ConfCORS
 	DB     ConfDB
 }
 
@@ -21,6 +22,12 @@ type ConfServer struct {
 	Debug        bool          `env:"SERVER_DEBUG,required"`
 }
 
+type ConfCORS struct {
+	AllowedOrigins string `env:"CORS_ALLOWED_ORIGINS,required"`
+	AllowedHeaders string `env:"CORS_ALLOWED_HEADERS,required"`
+	MaxAge         int    `env:"CORS_MAX_AGE,required"`
+}
+
 type ConfDB struct {
 	Host     string `env:"DB_HOST,required"`
 	Port     int    `env:"DB_PORT,required"`
diff --git a/go.mod b/go.mod
index 8b017f2..bfd4abf 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,7 @@ go 1.27
 require (
 	github.com/caarlos0/env/v11 v11.4.1
 	github.com/go-chi/chi/v5 v5.3.1
+	github.com/go-chi/cors v1.2.2
 	github.com/go-playground/validator/v10 v10.30.3
 	github.com/google/go-cmp v0.7.0
 	github.com/google/uuid v1.6.0
diff --git a/go.sum b/go.sum
index 10671c7..759c23d 100644
--- a/go.sum
+++ b/go.sum
@@ -16,6 +16,8 @@ github.com/gabriel-vasile/mimetype v1.4.13 h1:46nXokslUBsAJE/wMsp5gtO500a4F3Nkz9
 github.com/gabriel-vasile/mimetype v1.4.13/go.mod h1:d+9Oxyo1wTzWdyVUPMmXFvp4F9tea18J8ufA774AB3s=
 github.com/go-chi/chi/v5 v5.3.1 h1:3j4HZLGZQ3JpMCrPJF/Jl3mYJfWLKBfNJ6quurUGCf8=
 github.com/go-chi/chi/v5 v5.3.1/go.mod h1:R+tYY2hNuVUUjxoPtqUdgBqevM9s9njzkTLutVsOCto=
+github.com/go-chi/cors v1.2.2 h1:Jmey33TE+b+rB7fT8MUy1u0I4L+NARQlK6LhzKPSyQE=
+github.com/go-chi/cors v1.2.2/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
 github.com/go-openapi/jsonpointer v0.19.3/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34VGT37dQOVbmoatg=
 github.com/go-openapi/jsonpointer v0.19.5/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34VGT37dQOVbmoatg=
 github.com/go-openapi/jsonpointer v0.19.6 h1:eCs3fxoIi3Wh6vtgmLTOjdhSpiqphQ+DaPn38N2ZdrE=