From dc08e4098ffbb3d7d95c9decac7407e67349baa9 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Wed, 8 Apr 2020 09:13:26 -0700
Subject: [PATCH] add etag only for PUT or large chunked uploads

---
 weed/filer2/filechunks.go                   |  4 ++--
 weed/server/filer_server_handlers_write.go  | 13 ++++++++++---
 weed/server/volume_server_handlers_write.go |  8 ++++++++
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/weed/filer2/filechunks.go b/weed/filer2/filechunks.go
index e8e4c305b..48eaeea27 100644
--- a/weed/filer2/filechunks.go
+++ b/weed/filer2/filechunks.go
@@ -22,14 +22,14 @@ func TotalSize(chunks []*filer_pb.FileChunk) (size uint64) {
 
 func ETag(entry *filer_pb.Entry) (etag string) {
 	if entry.Attributes == nil || entry.Attributes.Md5 == nil {
-		ETagChunks(entry.Chunks)
+		return ETagChunks(entry.Chunks)
 	}
 	return fmt.Sprintf("%x", entry.Attributes.Md5)
 }
 
 func ETagEntry(entry *Entry) (etag string) {
 	if entry.Attr.Md5 == nil {
-		ETagChunks(entry.Chunks)
+		return ETagChunks(entry.Chunks)
 	}
 	return fmt.Sprintf("%x", entry.Attr.Md5)
 }
diff --git a/weed/server/filer_server_handlers_write.go b/weed/server/filer_server_handlers_write.go
index 33e6ee043..ce184875c 100644
--- a/weed/server/filer_server_handlers_write.go
+++ b/weed/server/filer_server_handlers_write.go
@@ -220,8 +220,13 @@ func (fs *FilerServer) uploadToVolumeServer(r *http.Request, u *url.URL, auth se
 	defer func() { stats.FilerRequestHistogram.WithLabelValues("postUpload").Observe(time.Since(start).Seconds()) }()
 
 	ret = &operation.UploadResult{}
+
 	md5Hash := md5.New()
-	var body = ioutil.NopCloser(io.TeeReader(r.Body, md5Hash))
+	body := r.Body
+	if r.Method == "PUT" {
+		// only PUT or large chunked files has Md5 in attributes
+		body = ioutil.NopCloser(io.TeeReader(r.Body, md5Hash))
+	}
 
 	request := &http.Request{
 		Method:        r.Method,
@@ -286,8 +291,10 @@ func (fs *FilerServer) uploadToVolumeServer(r *http.Request, u *url.URL, auth se
 		}
 	}
 	// use filer calculated md5 ETag, instead of the volume server crc ETag
-	md5value = md5Hash.Sum(nil)
-	ret.ETag = fmt.Sprintf("%x", md5value)
+	if r.Method == "PUT" {
+		md5value = md5Hash.Sum(nil)
+	}
+	ret.ETag = getEtag(resp)
 	return
 }
 
diff --git a/weed/server/volume_server_handlers_write.go b/weed/server/volume_server_handlers_write.go
index 3a71a1332..968ece11f 100644
--- a/weed/server/volume_server_handlers_write.go
+++ b/weed/server/volume_server_handlers_write.go
@@ -166,3 +166,11 @@ func setEtag(w http.ResponseWriter, etag string) {
 		}
 	}
 }
+
+func getEtag(resp *http.Response) (etag string){
+	etag = resp.Header.Get("ETag")
+	if strings.HasPrefix(etag, "\"") && strings.HasSuffix(etag, "\""){
+		return etag[1:len(etag)-1]
+	}
+	return
+}