From e60af7b82ec3a3b0b8788e205ff49cb0c3cf1946 Mon Sep 17 00:00:00 2001 From: Chris Lu Date: Mon, 26 May 2014 21:15:05 -0700 Subject: [PATCH] Add partial content request support. --- go/weed/weed_server/volume_server_handlers.go | 95 ++++++++++++++- .../volume_server_handlers_helper.go | 115 ++++++++++++++++++ 2 files changed, 205 insertions(+), 5 deletions(-) create mode 100644 go/weed/weed_server/volume_server_handlers_helper.go diff --git a/go/weed/weed_server/volume_server_handlers.go b/go/weed/weed_server/volume_server_handlers.go index 8c9c78137..70c1d70d5 100644 --- a/go/weed/weed_server/volume_server_handlers.go +++ b/go/weed/weed_server/volume_server_handlers.go @@ -7,7 +7,9 @@ import ( "code.google.com/p/weed-fs/go/stats" "code.google.com/p/weed-fs/go/storage" "code.google.com/p/weed-fs/go/topology" + "io" "mime" + "mime/multipart" "net/http" "strconv" "strings" @@ -20,10 +22,10 @@ func (vs *VolumeServer) storeHandler(w http.ResponseWriter, r *http.Request) { switch r.Method { case "GET": stats.ReadRequest() - vs.GetOrHeadHandler(w, r, true) + vs.GetOrHeadHandler(w, r) case "HEAD": stats.ReadRequest() - vs.GetOrHeadHandler(w, r, false) + vs.GetOrHeadHandler(w, r) case "DELETE": stats.DeleteRequest() secure(vs.whiteList, vs.DeleteHandler)(w, r) @@ -36,7 +38,7 @@ func (vs *VolumeServer) storeHandler(w http.ResponseWriter, r *http.Request) { } } -func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request, isGetMethod bool) { +func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request) { n := new(storage.Needle) vid, fid, filename, ext, _ := parseURLPath(r.URL.Path) volumeId, err := storage.NewVolumeId(vid) @@ -129,12 +131,95 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request, } n.Data = images.Resized(ext, n.Data, width, height) } - w.Header().Set("Content-Length", strconv.Itoa(len(n.Data))) - if isGetMethod { + + w.Header().Set("Accept-Ranges", "bytes") + if r.Method == "HEAD" { + w.Header().Set("Content-Length", strconv.Itoa(len(n.Data))) + return + } + rangeReq := r.Header.Get("Range") + if rangeReq == "" { + w.Header().Set("Content-Length", strconv.Itoa(len(n.Data))) if _, e = w.Write(n.Data); e != nil { glog.V(0).Infoln("response write error:", e) } + return } + + //the rest is dealing with partial content request + //mostly copy from src/pkg/net/http/fs.go + size := int64(len(n.Data)) + ranges, err := parseRange(rangeReq, size) + if err != nil { + http.Error(w, err.Error(), http.StatusRequestedRangeNotSatisfiable) + return + } + if sumRangesSize(ranges) > size { + // The total number of bytes in all the ranges + // is larger than the size of the file by + // itself, so this is probably an attack, or a + // dumb client. Ignore the range request. + ranges = nil + return + } + if len(ranges) == 0 { + return + } + if len(ranges) == 1 { + // RFC 2616, Section 14.16: + // "When an HTTP message includes the content of a single + // range (for example, a response to a request for a + // single range, or to a request for a set of ranges + // that overlap without any holes), this content is + // transmitted with a Content-Range header, and a + // Content-Length header showing the number of bytes + // actually transferred. + // ... + // A response to a request for a single range MUST NOT + // be sent using the multipart/byteranges media type." + ra := ranges[0] + w.Header().Set("Content-Length", strconv.FormatInt(ra.length, 10)) + w.Header().Set("Content-Range", ra.contentRange(size)) + w.WriteHeader(http.StatusPartialContent) + if _, e = w.Write(n.Data[ra.start : ra.start+ra.length]); e != nil { + glog.V(0).Infoln("response write error:", e) + } + return + } + // process mulitple ranges + for _, ra := range ranges { + if ra.start > size { + http.Error(w, "Out of Range", http.StatusRequestedRangeNotSatisfiable) + return + } + } + sendSize := rangesMIMESize(ranges, mtype, size) + pr, pw := io.Pipe() + mw := multipart.NewWriter(pw) + w.Header().Set("Content-Type", "multipart/byteranges; boundary="+mw.Boundary()) + sendContent := pr + defer pr.Close() // cause writing goroutine to fail and exit if CopyN doesn't finish. + go func() { + for _, ra := range ranges { + part, err := mw.CreatePart(ra.mimeHeader(mtype, size)) + if err != nil { + pw.CloseWithError(err) + return + } + if _, err = part.Write(n.Data[ra.start : ra.start+ra.length]); err != nil { + pw.CloseWithError(err) + return + } + } + mw.Close() + pw.Close() + }() + if w.Header().Get("Content-Encoding") == "" { + w.Header().Set("Content-Length", strconv.FormatInt(sendSize, 10)) + } + w.WriteHeader(http.StatusPartialContent) + io.CopyN(w, sendContent, sendSize) + } func (vs *VolumeServer) PostHandler(w http.ResponseWriter, r *http.Request) { diff --git a/go/weed/weed_server/volume_server_handlers_helper.go b/go/weed/weed_server/volume_server_handlers_helper.go new file mode 100644 index 000000000..6d21ffb62 --- /dev/null +++ b/go/weed/weed_server/volume_server_handlers_helper.go @@ -0,0 +1,115 @@ +package weed_server + +import ( + "errors" + "fmt" + "mime/multipart" + "net/textproto" + "strconv" + "strings" +) + +// copied from src/pkg/net/http/fs.go + +// httpRange specifies the byte range to be sent to the client. +type httpRange struct { + start, length int64 +} + +func (r httpRange) contentRange(size int64) string { + return fmt.Sprintf("bytes %d-%d/%d", r.start, r.start+r.length-1, size) +} + +func (r httpRange) mimeHeader(contentType string, size int64) textproto.MIMEHeader { + return textproto.MIMEHeader{ + "Content-Range": {r.contentRange(size)}, + "Content-Type": {contentType}, + } +} + +// parseRange parses a Range header string as per RFC 2616. +func parseRange(s string, size int64) ([]httpRange, error) { + if s == "" { + return nil, nil // header not present + } + const b = "bytes=" + if !strings.HasPrefix(s, b) { + return nil, errors.New("invalid range") + } + var ranges []httpRange + for _, ra := range strings.Split(s[len(b):], ",") { + ra = strings.TrimSpace(ra) + if ra == "" { + continue + } + i := strings.Index(ra, "-") + if i < 0 { + return nil, errors.New("invalid range") + } + start, end := strings.TrimSpace(ra[:i]), strings.TrimSpace(ra[i+1:]) + var r httpRange + if start == "" { + // If no start is specified, end specifies the + // range start relative to the end of the file. + i, err := strconv.ParseInt(end, 10, 64) + if err != nil { + return nil, errors.New("invalid range") + } + if i > size { + i = size + } + r.start = size - i + r.length = size - r.start + } else { + i, err := strconv.ParseInt(start, 10, 64) + if err != nil || i > size || i < 0 { + return nil, errors.New("invalid range") + } + r.start = i + if end == "" { + // If no end is specified, range extends to end of the file. + r.length = size - r.start + } else { + i, err := strconv.ParseInt(end, 10, 64) + if err != nil || r.start > i { + return nil, errors.New("invalid range") + } + if i >= size { + i = size - 1 + } + r.length = i - r.start + 1 + } + } + ranges = append(ranges, r) + } + return ranges, nil +} + +// countingWriter counts how many bytes have been written to it. +type countingWriter int64 + +func (w *countingWriter) Write(p []byte) (n int, err error) { + *w += countingWriter(len(p)) + return len(p), nil +} + +// rangesMIMESize returns the nunber of bytes it takes to encode the +// provided ranges as a multipart response. +func rangesMIMESize(ranges []httpRange, contentType string, contentSize int64) (encSize int64) { + var w countingWriter + mw := multipart.NewWriter(&w) + for _, ra := range ranges { + mw.CreatePart(ra.mimeHeader(contentType, contentSize)) + encSize += ra.length + } + mw.Close() + encSize += int64(w) + return +} + +func sumRangesSize(ranges []httpRange) (size int64) { + for _, ra := range ranges { + size += ra.length + } + return +}