Don't fetch metadata for plain object listing

Fetch metadata (xattr) for objects in a container ONLY when the
client asks for it (using content-type indicating JSON or XML response).
This avoids a lot of unnecessarry stat() and getxattr() calls whose
results would anyways be unused. The performance gain is obvious in
this case.

Change-Id: I4c8b0516dedd04553a5ed450bc855cafbfabada9
Signed-off-by: Prashanth Pai <ppai@redhat.com>
Reviewed-on: http://review.gluster.org/13573
Reviewed-by: Thiago da Silva <thiago@redhat.com>
Tested-by: Thiago da Silva <thiago@redhat.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/gluster/swift/common/DiskDir.py b/gluster/swift/common/DiskDir.py
index 31b923a..36504a6 100644
--- a/gluster/swift/common/DiskDir.py
+++ b/gluster/swift/common/DiskDir.py
@@ -368,7 +368,8 @@ class DiskDir(DiskCommon):
 
     def list_objects_iter(self, limit, marker, end_marker,
                           prefix, delimiter, path=None,
-                          storage_policy_index=0):
+                          storage_policy_index=0,
+                          out_content_type=None):
         """
         Returns tuple of name, created_at, size, content_type, etag.
         """
@@ -390,6 +391,7 @@ class DiskDir(DiskCommon):
         if objects:
             objects.sort()
         else:
+            # No objects in container , return empty list
             return container_list
 
         if end_marker:
@@ -417,6 +419,16 @@ class DiskDir(DiskCommon):
                 objects = filter_delimiter(objects, delimiter, prefix, marker,
                                            path)
 
+        if out_content_type == 'text/plain':
+            # The client is only asking for a plain list of objects and NOT
+            # asking for any extended information about objects such as
+            # bytes used or etag.
+            for obj in objects:
+                container_list.append((obj, 0, 0, 0, 0))
+                if len(container_list) >= limit:
+                        break
+            return container_list
+
         count = 0
         for obj in objects:
             obj_path = os.path.join(self.datadir, obj)