lfs: ask client to always send the same value for the HTTP header (#6369)

# Conflicts:
#	go.sum

CHANGELOG.md

@@ -22,6 +22,7 @@ All notable changes to Gogs are documented in this file.
 - Commit message contains keywords look like an issue reference no longer fails the push entirely. [#6289](https://github.com/gogs/gogs/issues/6289)
 - _Regression:_ When running Gogs on Windows, push commits no longer fail on a daily basis with the error "pre-receive hook declined". [#6316](https://github.com/gogs/gogs/issues/6316)
 - Auto-linked commit SHAs now have correct links. [#6300](https://github.com/gogs/gogs/issues/6300)
+- Git LFS client (with version >= 2.5.0) wasn't able to upload files with known format (e.g. PNG, JPEG), and the server is expecting the HTTP Header `Content-Type` to be `application/octet-stream`. The server now tells the LFS client to always use `Content-Type: application/octet-stream` when upload files.
 
 ### Removed
 

internal/route/lfs/batch.go

@@ -44,6 +44,11 @@ func serveBatch(c *macaron.Context, owner *db.User, repo *db.Repository) {
 				actions = batchActions{
 					Upload: &batchAction{
 						Href: fmt.Sprintf("%s/%s", baseHref, obj.Oid),
+						Header: map[string]string{
+							// NOTE: git-lfs v2.5.0 sets the Content-Type based on the uploaded file.
+							// This ensures that the client always uses the designated value for the header.
+							"Content-Type": "application/octet-stream",
+						},
 					},
 					Verify: &batchAction{
 						Href: fmt.Sprintf("%s/verify", baseHref),
@@ -136,7 +141,8 @@ type batchError struct {
 }
 
 type batchAction struct {
-	Href string `json:"href"`
+	Href   string            `json:"href"`
+	Header map[string]string `json:"header,omitempty"`
 }
 
 type batchActions struct {

internal/route/lfs/route.go

@@ -135,6 +135,8 @@ func authorize(mode db.AccessMode) macaron.Handler {
 			return
 		}
 
+		log.Trace("[LFS] Authorized user %q to %q", actor.Name, username+"/"+reponame)
+
 		c.Map(owner) // NOTE: Override actor
 		c.Map(repo)
 	}
@@ -144,10 +146,15 @@ func authorize(mode db.AccessMode) macaron.Handler {
 // When not, response given "failCode" as status code.
 func verifyHeader(key, value string, failCode int) macaron.Handler {
 	return func(c *macaron.Context) {
-		if !strings.Contains(c.Req.Header.Get(key), value) {
-			c.Status(failCode)
-			return
+		vals := c.Req.Header.Values(key)
+		for _, val := range vals {
+			if strings.Contains(val, value) {
+				return
+			}
 		}
+
+		log.Trace("[LFS] HTTP header %q does not contain value %q", key, value)
+		c.Status(failCode)
 	}
 }