update: 整理项目结构 重写中间件 提高复用性

internal/proxy/proxy.go

@@ -0,0 +1,166 @@
+package proxy
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"log/slog"
+	"mime"
+	"net/http"
+	"strings"
+	"sync/atomic"
+
+	"github.com/gin-gonic/gin"
+
+	"anyproxy/internal/middleware"
+)
+
+// 转发的总请求计数器
+var totalForwarded atomic.Int64
+
+// Proxy 封装具体的转发逻辑
+type Proxy struct {
+	Client *http.Client
+	Log    *slog.Logger
+}
+
+func New(client *http.Client, logger *slog.Logger) *Proxy {
+	return &Proxy{Client: client, Log: logger}
+}
+
+// HandleProxyPath 处理 /proxy/*path 形式的请求
+func (p *Proxy) HandleProxyPath(c *gin.Context) {
+	urlStr, err := BuildFromProxyPath(c.Param("proxyPath"), c.Request.URL.Query())
+	if err != nil {
+		p.writeError(c, http.StatusBadRequest, err)
+		return
+	}
+	p.forward(c, urlStr)
+}
+
+// HandleProtocol 处理 /:protocol/*remainder 形式的请求
+func (p *Proxy) HandleProtocol(c *gin.Context) {
+	urlStr, err := BuildFromProtocol(c.Param("protocol"), c.Param("remainder"), c.Request.URL.Query())
+	if err != nil {
+		p.writeError(c, http.StatusBadRequest, err)
+		return
+	}
+	p.forward(c, urlStr)
+}
+
+func (p *Proxy) writeError(c *gin.Context, code int, err error) {
+	c.JSON(code, gin.H{"error": err.Error(), "req_id": middleware.GetReqID(c)})
+}
+
+func (p *Proxy) forward(c *gin.Context, target string) {
+	reqID := middleware.GetReqID(c)
+	current := totalForwarded.Add(1)
+	p.Log.Debug("开始转发请求",
+		"req_id", reqID,
+		"count", current,
+		"method", c.Request.Method,
+		"target", target,
+		"uri", c.Request.RequestURI,
+	)
+
+	// 基于原始上下文创建上游请求（支持客户端断开时取消）
+	upReq, err := http.NewRequestWithContext(c.Request.Context(), c.Request.Method, target, c.Request.Body)
+	if err != nil {
+		p.Log.Error("创建上游请求失败", "req_id", reqID, "error", err)
+		p.writeError(c, http.StatusInternalServerError, errors.New("创建上游请求失败"))
+		return
+	}
+	upReq.Header = c.Request.Header.Clone()
+
+	// 仅在 SSE 时禁用压缩；稍后检测
+
+	resp, err := p.Client.Do(upReq)
+	if err != nil {
+		p.Log.Error("上游请求失败", "req_id", reqID, "error", err)
+		p.writeError(c, http.StatusBadGateway, errors.New("上游请求失败"))
+		return
+	}
+	defer resp.Body.Close()
+
+	mediaType, _, _ := mime.ParseMediaType(resp.Header.Get("Content-Type"))
+	isSSE := mediaType == "text/event-stream"
+
+	p.Log.Debug("上游响应", "req_id", reqID, "status", resp.StatusCode, "sse", isSSE)
+
+	// 复制上游响应头（最小化过滤）
+	for k, vs := range resp.Header {
+		for _, v := range vs { c.Header(k, v) }
+	}
+	if isSSE {
+		c.Writer.Header().Del("Content-Length")
+		c.Writer.Header().Del("Transfer-Encoding")
+		c.Header("Content-Type", "text/event-stream")
+		c.Header("Cache-Control", "no-cache")
+		c.Header("Connection", "keep-alive")
+		c.Header("X-Accel-Buffering", "no")
+		// 确保禁用上游压缩避免 SSE 事件被聚合
+		upReq.Header.Del("Accept-Encoding")
+	}
+	c.Status(resp.StatusCode)
+	if f, ok := c.Writer.(http.Flusher); ok { f.Flush() }
+
+	if !isSSE {
+		if _, err := io.Copy(c.Writer, resp.Body); err != nil {
+			p.Log.Error("写入响应体失败", "req_id", reqID, "error", err)
+		}
+		return
+	}
+
+	reader := bufio.NewReader(resp.Body)
+	w := c.Writer
+	flusher, _ := w.(http.Flusher)
+	for {
+		line, err := reader.ReadBytes('\n')
+		if len(line) > 0 {
+			if _, werr := w.Write(line); werr != nil {
+				p.Log.Warn("SSE写入失败", "req_id", reqID, "error", werr)
+				return
+			}
+			if flusher != nil { flusher.Flush() }
+		}
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				p.Log.Debug("SSE结束(EOF)", "req_id", reqID)
+			} else {
+				p.Log.Error("SSE读取失败", "req_id", reqID, "error", err)
+			}
+			return
+		}
+	}
+}
+
+// HelloPage 返回简单状态页面
+func HelloPage(c *gin.Context) {
+	count := totalForwarded.Load()
+
+	// 推断外部可见协议与主机（支持反向代理常见头）
+	scheme := "http"
+	if c.Request.TLS != nil { scheme = "https" }
+	if xf := c.GetHeader("X-Forwarded-Proto"); xf != "" {
+		// 取第一个
+		scheme = strings.TrimSpace(strings.Split(xf, ",")[0])
+	}
+	host := c.Request.Host
+	if xfh := c.GetHeader("X-Forwarded-Host"); xfh != "" {
+		host = strings.TrimSpace(strings.Split(xfh, ",")[0])
+	}
+	base := scheme + "://" + host
+
+	str := fmt.Sprintf("AnyProxy 服务器正在运行... 已转发 %d 个请求", count)
+	str += "\n\n使用方法:\n"
+	str += "方式1 - 直接协议路径: \n"
+	str += fmt.Sprintf("  目标URL: https://example.com/path --> 代理URL: %s/https/example.com/path\n", base)
+	str += fmt.Sprintf("  目标URL: http://example.com/path  --> 代理URL: %s/http/example.com/path\n\n", base)
+	str += "方式2 - 完整URL路径: \n"
+	str += fmt.Sprintf("  目标URL: https://example.com --> 代理URL: %s/proxy/https://example.com\n", base)
+	str += fmt.Sprintf("  目标URL: http://example.com  --> 代理URL: %s/proxy/http://example.com\n\n", base)
+	str += "目标URL必须以 https:// 或 http:// 开头。\n\n"
+	str += fmt.Sprintf("本机访问基地址: %s\n", base)
+	c.String(200, str)
+}