Golang多个域名的跨域资源共享的实现

package main

import (
	"net/http"
)

func main() {
	allowedOrigins := []string{
		"https://example1.com",
		"https://example2.com",
		"https://example3.com",
	}

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		origin := r.Header.Get("Origin")
		for _, o := range allowedOrigins {
			if origin == o {
				w.Header().Set("Access-Control-Allow-Origin", origin)
				w.Header().Set("Access-Control-Allow-Credentials", "true")
				w.Header().Set("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
				w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
				break
			}
		}

		// Handle preflight request
		if r.Method == http.MethodOptions {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		// Example response for other requests
		w.Write([]byte("CORS configured!"))
	})

	http.ListenAndServe(":8080", nil)
}

package main

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

func main() {
	allowedOrigins := []string{
		"https://example1.com",
		"https://example2.com",
		"https://example3.com",
	}

	r := gin.Default()

	// 自定义中间件处理 CORS
	r.Use(func(c *gin.Context) {
		origin := c.Request.Header.Get("Origin")
		for _, o := range allowedOrigins {
			if origin == o {
				c.Writer.Header().Set("Access-Control-Allow-Origin", origin)
				c.Writer.Header().Set("Access-Control-Allow-Credentials", "true")
				c.Writer.Header().Set("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
				c.Writer.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
				break
			}
		}

		// 如果是 OPTIONS 请求，提前返回
		if c.Request.Method == "OPTIONS" {
			c.AbortWithStatus(204)
			return
		}

		c.Next()
	})

	r.GET("/", func(c *gin.Context) {
		c.JSON(200, gin.H{"message": "CORS configured!"})
	})

	r.Run(":8080")
}

server {
    listen 80;
    server_name yourdomain.com;

    location / {
        set $cors "";
        if ($http_origin ~* "(https://example1\.com|https://example2\.com|https://example3\.com)") {
            set $cors $http_origin;
        }
        add_header Access-Control-Allow-Origin $cors;
        add_header Access-Control-Allow-Credentials true;
        add_header Access-Control-Allow-Methods "GET, POST, OPTIONS";
        add_header Access-Control-Allow-Headers "Content-Type, Authorization";

        # Pass the request to your Golang app
        proxy_pass http://127.0.0.1:8080;
    }
}