filer: support get file entry

weed/server/filer_server_handlers_read.go

@@ -21,7 +21,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
-
 // Validates the preconditions. Returns true if GET/HEAD operation should not proceed.
 // Preconditions supported are:
 //  If-Modified-Since
@@ -119,6 +118,11 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
+	if r.URL.Query().Has("metadata") {
+		writeJsonQuiet(w, r, http.StatusOK, entry)
+		return
+	}
+
 	etag := filer.ETagEntry(entry)
 	if checkPreconditions(w, r, entry) {
 		return