57 lines
1.6 KiB
Go
57 lines
1.6 KiB
Go
package middleware
|
|
|
|
import (
|
|
"net/http"
|
|
"strings"
|
|
)
|
|
|
|
// CORSConfig holds the configuration for CORS middleware.
|
|
type CORSConfig struct {
|
|
AllowedOrigins []string
|
|
}
|
|
|
|
// CORS adds Cross-Origin Resource Sharing headers to the response.
|
|
// If allowedOrigins contains "*", it allows all origins.
|
|
// Otherwise, it checks if the request origin is in the allowed list.
|
|
func CORSWithConfig(cfg CORSConfig) func(http.Handler) http.Handler {
|
|
allowAll := false
|
|
originsMap := make(map[string]bool)
|
|
for _, origin := range cfg.AllowedOrigins {
|
|
if origin == "*" {
|
|
allowAll = true
|
|
break
|
|
}
|
|
originsMap[strings.ToLower(origin)] = true
|
|
}
|
|
|
|
return func(next http.Handler) http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
origin := r.Header.Get("Origin")
|
|
|
|
if allowAll {
|
|
w.Header().Set("Access-Control-Allow-Origin", "*")
|
|
} else if origin != "" && originsMap[strings.ToLower(origin)] {
|
|
w.Header().Set("Access-Control-Allow-Origin", origin)
|
|
w.Header().Set("Vary", "Origin")
|
|
}
|
|
|
|
w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS, PATCH")
|
|
w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
|
|
w.Header().Set("Access-Control-Max-Age", "86400")
|
|
|
|
// Handle preflight requests
|
|
if r.Method == http.MethodOptions {
|
|
w.WriteHeader(http.StatusOK)
|
|
return
|
|
}
|
|
|
|
next.ServeHTTP(w, r)
|
|
})
|
|
}
|
|
}
|
|
|
|
// CORS is a compatibility wrapper that allows all origins.
|
|
// Deprecated: Use CORSWithConfig for more control.
|
|
func CORS(next http.Handler) http.Handler {
|
|
return CORSWithConfig(CORSConfig{AllowedOrigins: []string{"*"}})(next)
|
|
}
|