refactor: oci image proxy

proxy/docker.go

@@ -2,19 +2,21 @@ package proxy
 
 import (
 	"context"
-	"encoding/json"
+
+	"github.com/go-json-experiment/json"
+
 	"fmt"
-
-	"github.com/infinite-iroha/touka"
-
-	"ghproxy/config"
-	"ghproxy/weakcache"
-	"io"
 	"net/http"
+	"net/url"
 	"strconv"
 	"strings"
 
+	"ghproxy/config"
+	"ghproxy/weakcache"
+
+	"github.com/WJQSERVER-STUDIO/go-utils/iox"
 	"github.com/WJQSERVER-STUDIO/go-utils/limitreader"
+	"github.com/infinite-iroha/touka"
 )
 
 var (
@@ -22,83 +24,109 @@ var (
 	ghcrTarget      = "ghcr.io"
 )
 
+// cache 用于存储认证令牌, 避免重复获取
 var cache *weakcache.Cache[string]
 
+// imageInfo 结构体用于存储镜像的相关信息
 type imageInfo struct {
 	User  string
 	Repo  string
 	Image string
 }
 
+// InitWeakCache 初始化弱引用缓存
 func InitWeakCache() *weakcache.Cache[string] {
+	// 使用默认过期时间和容量为100创建一个新的弱引用缓存
 	cache = weakcache.NewCache[string](weakcache.DefaultExpiration, 100)
 	return cache
 }
 
+// GhcrWithImageRouting 处理带有镜像路由的请求, 根据目标路由到不同的Docker注册表
 func GhcrWithImageRouting(cfg *config.Config) touka.HandlerFunc {
 	return func(c *touka.Context) {
+		reqTarget := c.Param("target")     // 请求中指定的目标 (如 docker.io, ghcr.io, gcr.io)
+		reqImageUser := c.Param("user")    // 镜像用户
+		reqImageName := c.Param("repo")    // 镜像仓库名
+		reqFilePath := c.Param("filepath") // 镜像文件路径
 
-		charToFind := '.'
+		// 构造完整的镜像路径
-		reqTarget := c.Param("target")
+		path := fmt.Sprintf("%s/%s%s", reqImageUser, reqImageName, reqFilePath)
-		reqImageUser := c.Param("user")
+		var target string
-		reqImageName := c.Param("repo")
-		reqFilePath := c.Param("filepath")
 
-		path := fmt.Sprintf("%s/%s/%s", reqImageUser, reqImageName, reqFilePath)
+		// 根据 reqTarget 智能判断实际的目标注册表
-		target := ""
+		switch {
-
+		case reqTarget == "docker.io":
-		if strings.ContainsRune(reqTarget, charToFind) {
+			target = dockerhubTarget // Docker Hub
-			switch reqTarget {
+		case reqTarget == "ghcr.io":
-			case "docker.io":
+			target = ghcrTarget // GitHub Container Registry
-				target = dockerhubTarget
+		case strings.HasSuffix(reqTarget, ".gcr.io"), reqTarget == "gcr.io":
-			case "ghcr.io":
+			target = reqTarget // Google Container Registry 及其子域名
-				target = ghcrTarget
+		default:
-			default:
+			// 如果 reqTarget 包含点, 则假定它是一个完整的域名
-				target = reqTarget
+			for _, r := range reqTarget {
+				if r == '.' {
+					target = reqTarget
+					break
+				}
 			}
-		} else {
-			path = c.GetRequestURI()
-			reqImageUser = c.Param("target")
-			reqImageName = c.Param("user")
 		}
+
+		// 封装镜像信息
 		image := &imageInfo{
 			User:  reqImageUser,
 			Repo:  reqImageName,
 			Image: fmt.Sprintf("%s/%s", reqImageUser, reqImageName),
 		}
 
+		// 调用 GhcrToTarget 处理实际的代理请求
 		GhcrToTarget(c, cfg, target, path, image)
-
 	}
-
 }
 
+// GhcrToTarget 根据配置和目标信息将请求代理到上游Docker注册表
 func GhcrToTarget(c *touka.Context, cfg *config.Config, target string, path string, image *imageInfo) {
-	if cfg.Docker.Enabled {
+	// 检查Docker代理是否启用
-		var ctx = c.Request.Context()
+	if !cfg.Docker.Enabled {
-		if target != "" {
-			GhcrRequest(ctx, c, "https://"+target+"/v2/"+path+"?"+c.GetReqQueryString(), image, cfg, target)
-		} else {
-			if cfg.Docker.Target == "ghcr" {
-				GhcrRequest(ctx, c, "https://"+ghcrTarget+c.GetRequestURI(), image, cfg, ghcrTarget)
-			} else if cfg.Docker.Target == "dockerhub" {
-				GhcrRequest(ctx, c, "https://"+dockerhubTarget+c.GetRequestURI(), image, cfg, dockerhubTarget)
-			} else if cfg.Docker.Target != "" {
-				// 自定义taget
-				GhcrRequest(ctx, c, "https://"+cfg.Docker.Target+c.GetRequestURI(), image, cfg, cfg.Docker.Target)
-			} else {
-				// 配置为空
-				ErrorPage(c, NewErrorWithStatusLookup(403, "Docker Target is not set"))
-				return
-			}
-		}
-
-	} else {
 		ErrorPage(c, NewErrorWithStatusLookup(403, "Docker is not Allowed"))
 		return
 	}
+
+	var destUrl string        // 最终代理的目标URL
+	var upstreamTarget string // 实际的上游目标域名
+	var ctx = c.Request.Context()
+
+	// 根据是否指定 target 来确定上游目标和目标URL
+	if target != "" {
+		upstreamTarget = target
+		// 构造目标URL, 拼接 v2/ 路径和原始查询参数
+		destUrl = "https://" + upstreamTarget + "/v2/" + path
+		if query := c.GetReqQueryString(); query != "" {
+			destUrl += "?" + query
+		}
+		c.Debugf("Proxying to target %s: %s", upstreamTarget, destUrl)
+	} else {
+		// 如果未指定 target, 则根据配置的默认目标进行代理
+		switch cfg.Docker.Target {
+		case "ghcr":
+			upstreamTarget = ghcrTarget
+		case "dockerhub":
+			upstreamTarget = dockerhubTarget
+		case "":
+			ErrorPage(c, NewErrorWithStatusLookup(403, "Docker Target is not set"))
+			return
+		default:
+			upstreamTarget = cfg.Docker.Target
+		}
+		// 使用原始请求URI构建目标URL
+		destUrl = "https://" + upstreamTarget + c.GetRequestURI()
+		c.Debugf("Proxying to default target %s: %s", upstreamTarget, destUrl)
+	}
+
+	// 执行实际的代理请求
+	GhcrRequest(ctx, c, destUrl, image, cfg, upstreamTarget)
 }
 
+// GhcrRequest 执行对Docker注册表的HTTP请求, 处理认证和重定向
 func GhcrRequest(ctx context.Context, c *touka.Context, u string, image *imageInfo, cfg *config.Config, target string) {
 
 	var (
@@ -108,23 +136,25 @@ func GhcrRequest(ctx context.Context, c *touka.Context, u string, image *imageIn
 		err    error
 	)
 
+	// 当请求上下文被取消时, 确保关闭响应和请求体
 	go func() {
 		<-ctx.Done()
 		if resp != nil && resp.Body != nil {
-			resp.Body.Close()
+			_ = resp.Body.Close()
 		}
-		if req != nil {
+		if req != nil && req.Body != nil {
-			req.Body.Close()
+			_ = req.Body.Close()
 		}
 	}()
 
 	method = c.Request.Method
 	ghcrclient := c.GetHTTPC()
 
+	// 构建初始请求
 	rb := ghcrclient.NewRequestBuilder(method, u)
-	rb.NoDefaultHeaders()
+	rb.NoDefaultHeaders()      // 不使用默认头部, 以便完全控制
-	rb.SetBody(c.Request.Body)
+	rb.SetBody(c.Request.Body) // 设置请求体
-	rb.WithContext(ctx)
+	rb.WithContext(ctx)        // 设置请求上下文
 
 	req, err = rb.Build()
 	if err != nil {
@@ -132,80 +162,138 @@ func GhcrRequest(ctx context.Context, c *touka.Context, u string, image *imageIn
 		return
 	}
 
+	// 复制客户端请求的头部到代理请求
 	copyHeader(c.Request.Header, req.Header)
 
+	// 确保 Accept 头部被正确设置
+	if acceptHeader, ok := c.Request.Header["Accept"]; ok {
+		req.Header["Accept"] = acceptHeader
+	}
+
+	// 设置 Host 头部为上游目标
 	req.Header.Set("Host", target)
+
+	// 尝试从缓存中获取并使用认证令牌
 	if image != nil {
 		token, exist := cache.Get(image.Image)
 		if exist {
-			c.Debugf("Use Cache Token: %s", token)
 			req.Header.Set("Authorization", "Bearer "+token)
 		}
 	}
 
+	// 发送初始请求
 	resp, err = ghcrclient.Do(req)
 	if err != nil {
 		HandleError(c, fmt.Sprintf("Failed to send request: %v", err))
 		return
 	}
 
-	switch resp.StatusCode {
+	// 处理 401 Unauthorized 或 404 Not Found 响应, 尝试重新认证并重试
+	if resp.StatusCode == 401 || resp.StatusCode == 404 {
+		// 对于 /v2/ 的请求不进行重试, 因为它通常用于发现认证端点
+		shouldRetry := string(c.GetRequestURIPath()) != "/v2/"
+		originalStatusCode := resp.StatusCode
+		c.Debugf("Initial request failed with status %d. Retry eligibility: %t", originalStatusCode, shouldRetry)
+		_ = resp.Body.Close() // 关闭当前响应体
 
-	case 401:
+		if shouldRetry {
-		// 请求target /v2/路径
-		if string(c.GetRequestURIPath()) != "/v2/" {
-			resp.Body.Close()
 			if image == nil {
-				ErrorPage(c, NewErrorWithStatusLookup(401, "Unauthorized"))
+				ErrorPage(c, NewErrorWithStatusLookup(originalStatusCode, "Unauthorized"))
 				return
 			}
+			// 获取新的认证令牌
 			token := ChallengeReq(target, image, ctx, c)
 
-			// 更新kv
 			if token != "" {
-				c.Debugf("Update Cache Token: %s", token)
+				c.Debugf("Successfully obtained auth token. Retrying request.")
-				cache.Put(image.Image, token)
+				// 重新构建并发送请求
-			}
+				rb_retry := ghcrclient.NewRequestBuilder(method, u)
+				rb_retry.NoDefaultHeaders()
+				rb_retry.SetBody(c.Request.Body)
+				rb_retry.WithContext(ctx)
 
-			rb := ghcrclient.NewRequestBuilder(string(method), u)
+				req_retry, err_retry := rb_retry.Build()
-			rb.NoDefaultHeaders()
+				if err_retry != nil {
-			rb.SetBody(c.Request.Body)
+					HandleError(c, fmt.Sprintf("Failed to create retry request: %v", err_retry))
-			rb.WithContext(ctx)
+					return
+				}
 
-			req, err = rb.Build()
+				copyHeader(c.Request.Header, req_retry.Header) // 复制原始头部
-			if err != nil {
+				if acceptHeader, ok := c.Request.Header["Accept"]; ok {
-				HandleError(c, fmt.Sprintf("Failed to create request: %v", err))
+					req_retry.Header["Accept"] = acceptHeader
-				return
+				}
-			}
 
-			copyHeader(c.Request.Header, req.Header)
+				req_retry.Header.Set("Host", target)                   // 设置 Host 头部
+				req_retry.Header.Set("Authorization", "Bearer "+token) // 使用新令牌
 
-			req.Header.Set("Host", target)
+				c.Debugf("Executing retry request. Method: %s, URL: %s", req_retry.Method, req_retry.URL.String())
-			if token != "" {
-				req.Header.Set("Authorization", "Bearer "+token)
-			}
 
-			resp, err = ghcrclient.Do(req)
+				resp_retry, err_retry := ghcrclient.Do(req_retry)
-			if err != nil {
+				if err_retry != nil {
-				HandleError(c, fmt.Sprintf("Failed to send request: %v", err))
+					HandleError(c, fmt.Sprintf("Failed to send retry request: %v", err_retry))
-				return
+					return
+				}
+				c.Debugf("Retry request completed with status code: %d", resp_retry.StatusCode)
+				resp = resp_retry // 更新响应为重试后的响应
+			} else {
+				c.Warnf("Failed to obtain auth token. Cannot retry.")
 			}
 		}
+	}
 
-	case 404: // 错误处理(404)
+	// 透明地处理 302 Found 或 307 Temporary Redirect 重定向
-		ErrorPage(c, NewErrorWithStatusLookup(404, "Page Not Found (From Github)"))
+	if resp.StatusCode == http.StatusFound || resp.StatusCode == http.StatusTemporaryRedirect {
-		return
+		location := resp.Header.Get("Location")
-	case 302, 301:
+		if location == "" {
-		finalURL := resp.Header.Get("Location")
+			HandleError(c, "Redirect response missing Location header")
-		if finalURL != "" {
-			err = resp.Body.Close()
-			if err != nil {
-				c.Errorf("Failed to close response body: %v", err)
-			}
-			c.Infof("Internal Redirecting to %s", finalURL)
-			GhcrRequest(ctx, c, finalURL, image, cfg, target)
 			return
 		}
+
+		redirectURL, err := url.Parse(location)
+		if err != nil {
+			HandleError(c, fmt.Sprintf("Failed to parse redirect location: %v", err))
+			return
+		}
+
+		// 如果 Location 是相对路径, 则根据原始请求的 URL 解析为绝对路径
+		if !redirectURL.IsAbs() {
+			originalURL := resp.Request.URL
+			redirectURL = originalURL.ResolveReference(redirectURL)
+			c.Debugf("Resolved relative redirect to absolute URL: %s", redirectURL.String())
+		}
+
+		c.Debugf("Handling redirect. Status: %d, Final Location: %s", resp.StatusCode, redirectURL.String())
+		_ = resp.Body.Close() // 关闭当前响应体
+
+		// 创建并发送重定向请求, 通常使用 GET 方法
+		redirectReq, err := http.NewRequestWithContext(ctx, "GET", redirectURL.String(), nil)
+		if err != nil {
+			HandleError(c, fmt.Sprintf("Failed to create redirect request: %v", err))
+			return
+		}
+		redirectReq.Header.Set("User-Agent", c.Request.UserAgent()) // 复制 User-Agent
+
+		c.Debugf("Executing redirect request to: %s", redirectURL.String())
+		redirectResp, err := ghcrclient.Do(redirectReq)
+		if err != nil {
+			HandleError(c, fmt.Sprintf("Failed to execute redirect request to %s: %v", redirectURL.String(), err))
+			return
+		}
+		c.Debugf("Redirect request to %s completed with status %d", redirectURL.String(), redirectResp.StatusCode)
+		resp = redirectResp // 更新响应为重定向后的响应
+	}
+
+	// 如果最终响应是 404, 则读取响应体并返回自定义错误页面
+	if resp.StatusCode == 404 {
+		bodyBytes, err := iox.ReadAll(resp.Body)
+		if err != nil {
+			c.Warnf("Failed to read upstream 404 response body: %v", err)
+		} else {
+			c.Warnf("Upstream 404 response body: %s", string(bodyBytes))
+		}
+		_ = resp.Body.Close()
+		ErrorPage(c, NewErrorWithStatusLookup(404, "Page Not Found (From Upstream)"))
+		return
 	}
 
 	var (
@@ -214,6 +302,7 @@ func GhcrRequest(ctx context.Context, c *touka.Context, u string, image *imageIn
 		sizelimit     int
 	)
 
+	// 获取配置中的大小限制并转换单位 (MB -> Byte)
 	sizelimit = cfg.Server.SizeLimit * 1024 * 1024
 	contentLength = resp.Header.Get("Content-Length")
 	if contentLength != "" {
@@ -221,77 +310,85 @@ func GhcrRequest(ctx context.Context, c *touka.Context, u string, image *imageIn
 		bodySize, err = strconv.Atoi(contentLength)
 		if err != nil {
 			c.Warnf("%s %s %s %s %s Content-Length header is not a valid integer: %v", c.ClientIP(), c.Request.Method, c.Request.URL.Path, c.UserAgent(), c.Request.Proto, err)
-			bodySize = -1
+			bodySize = -1 // 无法解析则设置为 -1
 		}
+		// 如果内容大小超出限制, 返回 301 重定向到原始上游URL
 		if err == nil && bodySize > sizelimit {
 			finalURL := resp.Request.URL.String()
-			err = resp.Body.Close()
+			_ = resp.Body.Close() // 关闭响应体
-			if err != nil {
-				c.Errorf("Failed to close response body: %v", err)
-			}
 			c.Redirect(301, finalURL)
 			c.Warnf("%s %s %s %s %s Final-URL: %s Size-Limit-Exceeded: %d", c.ClientIP(), c.Request.Method, c.Request.URL.Path, c.UserAgent(), c.Request.Proto, finalURL, bodySize)
 			return
 		}
 	}
 
+	// 将上游响应头部复制到客户端响应
 	c.SetHeaders(resp.Header)
-
+	// 设置客户端响应状态码
 	c.Status(resp.StatusCode)
-
 	bodyReader := resp.Body
 
+	// 如果启用了带宽限制, 则使用限速读取器
 	if cfg.RateLimit.BandwidthLimit.Enabled {
 		bodyReader = limitreader.NewRateLimitedReader(bodyReader, bandwidthLimit, int(bandwidthBurst), ctx)
 	}
 
+	// 根据 Content-Length 设置响应体流
 	if contentLength != "" {
 		c.SetBodyStream(bodyReader, bodySize)
 		return
 	}
-	c.SetBodyStream(bodyReader, -1)
+	c.SetBodyStream(bodyReader, -1) // Content-Length 未知
-
 }
 
+// AuthToken 用于解析认证响应中的令牌
 type AuthToken struct {
 	Token string `json:"token"`
 }
 
+// ChallengeReq 执行认证挑战流程, 获取新的认证令牌
 func ChallengeReq(target string, image *imageInfo, ctx context.Context, c *touka.Context) (token string) {
 	var resp401 *http.Response
 	var req401 *http.Request
 	var err error
 	ghcrclient := c.GetHTTPC()
 
+	// 对 /v2/ 端点发送 GET 请求以触发认证挑战
 	rb401 := ghcrclient.NewRequestBuilder("GET", "https://"+target+"/v2/")
 	rb401.NoDefaultHeaders()
 	rb401.WithContext(ctx)
-	rb401.AddHeader("User-Agent", "docker/28.1.1 go/go1.23.8 git-commit/01f442b kernel/6.12.25-amd64 os/linux arch/amd64 UpstreamClient(Docker-Client/28.1.1 ")
+	//rb401.AddHeader("User-Agent", "docker/28.1.1 go/go1.23.8 git-commit/01f442b kernel/6.12.25-amd64 os/linux arch/amd64 UpstreamClient(Docker-Client/28.1.1 ")
 	req401, err = rb401.Build()
 	if err != nil {
 		HandleError(c, fmt.Sprintf("Failed to create request: %v", err))
 		return
 	}
-	req401.Header.Set("Host", target)
+	req401.Header.Set("Host", target) // 设置 Host 头部
 
 	resp401, err = ghcrclient.Do(req401)
 	if err != nil {
 		HandleError(c, fmt.Sprintf("Failed to send request: %v", err))
 		return
 	}
-	defer resp401.Body.Close()
+	defer func() {
+		_ = resp401.Body.Close() // 确保响应体关闭
+	}()
+
+	// 解析 Www-Authenticate 头部, 获取认证领域和参数
 	bearer, err := parseBearerWWWAuthenticateHeader(resp401.Header.Get("Www-Authenticate"))
 	if err != nil {
 		c.Errorf("Failed to parse Www-Authenticate header: %v", err)
 		return
 	}
 
+	// 构建认证范围 (scope), 通常是 repository:<image_name>:pull
 	scope := fmt.Sprintf("repository:%s:pull", image.Image)
 
+	// 使用解析到的 Realm 和 Service, 以及 scope 请求认证令牌
 	getAuthRB := ghcrclient.NewRequestBuilder("GET", bearer.Realm).
 		NoDefaultHeaders().
 		WithContext(ctx).
-		AddHeader("User-Agent", "docker/28.1.1 go/go1.23.8 git-commit/01f442b kernel/6.12.25-amd64 os/linux arch/amd64 UpstreamClient(Docker-Client/28.1.1 ").
+		//AddHeader("User-Agent", "docker/28.1.1 go/go1.23.8 git-commit/01f442b kernel/6.12.25-amd64 os/linux arch/amd64 UpstreamClient(Docker-Client/28.1.1 ").
 		SetHeader("Host", bearer.Service).
 		AddQueryParam("service", bearer.Service).
 		AddQueryParam("scope", scope)
@@ -307,24 +404,25 @@ func ChallengeReq(target string, image *imageInfo, ctx context.Context, c *touka
 		c.Errorf("Failed to send request: %v", err)
 		return
 	}
+	defer func() {
+		_ = authResp.Body.Close() // 确保响应体关闭
+	}()
 
-	defer authResp.Body.Close()
+	// 读取认证响应体
-
+	bodyBytes, err := iox.ReadAll(authResp.Body)
-	bodyBytes, err := io.ReadAll(authResp.Body)
 	if err != nil {
 		c.Errorf("Failed to read auth response body: %v", err)
 		return
 	}
 
-	// 解码json
+	// 解码 JSON 响应以获取令牌
 	var authToken AuthToken
 	err = json.Unmarshal(bodyBytes, &authToken)
 	if err != nil {
 		c.Errorf("Failed to decode auth response body: %v", err)
 		return
 	}
-	token = authToken.Token
+	token = authToken.Token // 提取令牌
 
 	return token
-
 }