package weed_server import ( "bytes" "context" "fmt" "io" "math" "mime" "net/http" "path/filepath" "strconv" "strings" "time" "github.com/seaweedfs/seaweedfs/weed/s3api/s3_constants" "github.com/seaweedfs/seaweedfs/weed/util/mem" "github.com/seaweedfs/seaweedfs/weed/filer" "github.com/seaweedfs/seaweedfs/weed/glog" "github.com/seaweedfs/seaweedfs/weed/images" "github.com/seaweedfs/seaweedfs/weed/pb/filer_pb" "github.com/seaweedfs/seaweedfs/weed/stats" "github.com/seaweedfs/seaweedfs/weed/util" ) // Validates the preconditions. Returns true if GET/HEAD operation should not proceed. // Preconditions supported are: // // If-Modified-Since // If-Unmodified-Since // If-Match // If-None-Match func checkPreconditions(w http.ResponseWriter, r *http.Request, entry *filer.Entry) bool { etag := filer.ETagEntry(entry) /// When more than one conditional request header field is present in a /// request, the order in which the fields are evaluated becomes /// important. In practice, the fields defined in this document are /// consistently implemented in a single, logical order, since "lost /// update" preconditions have more strict requirements than cache /// validation, a validated cache is more efficient than a partial /// response, and entity tags are presumed to be more accurate than date /// validators. https://tools.ietf.org/html/rfc7232#section-5 if entry.Attr.Mtime.IsZero() { return false } w.Header().Set("Last-Modified", entry.Attr.Mtime.UTC().Format(http.TimeFormat)) ifMatchETagHeader := r.Header.Get("If-Match") ifUnmodifiedSinceHeader := r.Header.Get("If-Unmodified-Since") if ifMatchETagHeader != "" { if util.CanonicalizeETag(etag) != util.CanonicalizeETag(ifMatchETagHeader) { w.WriteHeader(http.StatusPreconditionFailed) return true } } else if ifUnmodifiedSinceHeader != "" { if t, parseError := time.Parse(http.TimeFormat, ifUnmodifiedSinceHeader); parseError == nil { if t.Before(entry.Attr.Mtime) { w.WriteHeader(http.StatusPreconditionFailed) return true } } } ifNoneMatchETagHeader := r.Header.Get("If-None-Match") ifModifiedSinceHeader := r.Header.Get("If-Modified-Since") if ifNoneMatchETagHeader != "" { if util.CanonicalizeETag(etag) == util.CanonicalizeETag(ifNoneMatchETagHeader) { w.WriteHeader(http.StatusNotModified) return true } } else if ifModifiedSinceHeader != "" { if t, parseError := time.Parse(http.TimeFormat, ifModifiedSinceHeader); parseError == nil { if !t.Before(entry.Attr.Mtime) { w.WriteHeader(http.StatusNotModified) return true } } } return false } func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request) { path := r.URL.Path isForDirectory := strings.HasSuffix(path, "/") if isForDirectory && len(path) > 1 { path = path[:len(path)-1] } entry, err := fs.filer.FindEntry(context.Background(), util.FullPath(path)) if err != nil { if path == "/" { fs.listDirectoryHandler(w, r) return } if err == filer_pb.ErrNotFound { glog.V(2).Infof("Not found %s: %v", path, err) stats.FilerHandlerCounter.WithLabelValues(stats.ErrorReadNotFound).Inc() w.WriteHeader(http.StatusNotFound) } else { glog.Errorf("Internal %s: %v", path, err) stats.FilerHandlerCounter.WithLabelValues(stats.ErrorReadInternal).Inc() w.WriteHeader(http.StatusInternalServerError) } return } query := r.URL.Query() if entry.IsDirectory() { if fs.option.DisableDirListing { w.WriteHeader(http.StatusForbidden) return } if query.Get("metadata") == "true" { writeJsonQuiet(w, r, http.StatusOK, entry) return } if entry.Attr.Mime == "" || (entry.Attr.Mime == s3_constants.FolderMimeType && r.Header.Get(s3_constants.AmzIdentityId) == "") { // return index of directory for non s3 gateway fs.listDirectoryHandler(w, r) return } // inform S3 API this is a user created directory key object w.Header().Set(s3_constants.X_SeaweedFS_Header_Directory_Key, "true") } if isForDirectory && entry.Attr.Mime != s3_constants.FolderMimeType { w.WriteHeader(http.StatusNotFound) return } if query.Get("metadata") == "true" { if query.Get("resolveManifest") == "true" { if entry.Chunks, _, err = filer.ResolveChunkManifest( fs.filer.MasterClient.GetLookupFileIdFunction(), entry.GetChunks(), 0, math.MaxInt64); err != nil { err = fmt.Errorf("failed to resolve chunk manifest, err: %s", err.Error()) writeJsonError(w, r, http.StatusInternalServerError, err) return } } writeJsonQuiet(w, r, http.StatusOK, entry) return } etag := filer.ETagEntry(entry) if checkPreconditions(w, r, entry) { return } w.Header().Set("Accept-Ranges", "bytes") // mime type mimeType := entry.Attr.Mime if mimeType == "" { if ext := filepath.Ext(entry.Name()); ext != "" { mimeType = mime.TypeByExtension(ext) } } if mimeType != "" { w.Header().Set("Content-Type", mimeType) } else { w.Header().Set("Content-Type", "application/octet-stream") } // print out the header from extended properties for k, v := range entry.Extended { if !strings.HasPrefix(k, "xattr-") { // "xattr-" prefix is set in filesys.XATTR_PREFIX w.Header().Set(k, string(v)) } } //Seaweed custom header are not visible to Vue or javascript seaweedHeaders := []string{} for header := range w.Header() { if strings.HasPrefix(header, "Seaweed-") { seaweedHeaders = append(seaweedHeaders, header) } } seaweedHeaders = append(seaweedHeaders, "Content-Disposition") w.Header().Set("Access-Control-Expose-Headers", strings.Join(seaweedHeaders, ",")) //set tag count tagCount := 0 for k := range entry.Extended { if strings.HasPrefix(k, s3_constants.AmzObjectTagging+"-") { tagCount++ } } if tagCount > 0 { w.Header().Set(s3_constants.AmzTagCount, strconv.Itoa(tagCount)) } setEtag(w, etag) filename := entry.Name() adjustPassthroughHeaders(w, r, filename) totalSize := int64(entry.Size()) if r.Method == "HEAD" { w.Header().Set("Content-Length", strconv.FormatInt(totalSize, 10)) return } if rangeReq := r.Header.Get("Range"); rangeReq == "" { ext := filepath.Ext(filename) if len(ext) > 0 { ext = strings.ToLower(ext) } width, height, mode, shouldResize := shouldResizeImages(ext, r) if shouldResize { data := mem.Allocate(int(totalSize)) defer mem.Free(data) err := filer.ReadAll(data, fs.filer.MasterClient, entry.GetChunks()) if err != nil { glog.Errorf("failed to read %s: %v", path, err) w.WriteHeader(http.StatusInternalServerError) return } rs, _, _ := images.Resized(ext, bytes.NewReader(data), width, height, mode) io.Copy(w, rs) return } } processRangeRequest(r, w, totalSize, mimeType, func(writer io.Writer, offset int64, size int64) error { if offset+size <= int64(len(entry.Content)) { _, err := writer.Write(entry.Content[offset : offset+size]) if err != nil { stats.FilerHandlerCounter.WithLabelValues(stats.ErrorWriteEntry).Inc() glog.Errorf("failed to write entry content: %v", err) } return err } chunks := entry.GetChunks() if entry.IsInRemoteOnly() { dir, name := entry.FullPath.DirAndName() if resp, err := fs.CacheRemoteObjectToLocalCluster(context.Background(), &filer_pb.CacheRemoteObjectToLocalClusterRequest{ Directory: dir, Name: name, }); err != nil { stats.FilerHandlerCounter.WithLabelValues(stats.ErrorReadCache).Inc() glog.Errorf("CacheRemoteObjectToLocalCluster %s: %v", entry.FullPath, err) return fmt.Errorf("cache %s: %v", entry.FullPath, err) } else { chunks = resp.Entry.GetChunks() } } err = filer.StreamContentWithThrottler(fs.filer.MasterClient, writer, chunks, offset, size, fs.option.DownloadMaxBytesPs) if err != nil { stats.FilerHandlerCounter.WithLabelValues(stats.ErrorReadStream).Inc() glog.Errorf("failed to stream content %s: %v", r.URL, err) } return err }) }