pithos: Slight modifications in the backends

* Do not generate/register a mapfile for zero size objects since
there are not stored in the storage backend.
* Several minor fixes

snf-pithos-backend/pithos/backends/lib/sqlalchemy/node.py

@@ -771,7 +771,7 @@ class Node(DBWorker):
                        available=True, map_check_timestamp=None,
                        mapfile=None, is_snapshot=False):
         """Create a new version from the given properties.
-           Return the (serial, mtime) of the new version.
+           Return the (serial, mtime, mapfile) of the new version.
 
            If mapfile is not None, set mapfile to this value.
            Otherwise, assign to the mapfile a new unique identifier.
@@ -780,6 +780,12 @@ class Node(DBWorker):
         """
 
         mtime = time()
+        if size == 0:
+            mapfile = None
+        elif mapfile is None:
+            mapfile = functions.concat(literal(self.mapfile_prefix),
+                                       functions.next_value(self.mapfile_seq))
+
         s = self.versions.insert().returning(self.versions.c.serial,
                                              self.versions.c.mtime,
                                              self.versions.c.mapfile)
@@ -788,9 +794,7 @@ class Node(DBWorker):
             mtime=mtime, muser=muser, uuid=uuid, checksum=checksum,
             cluster=cluster, available=available,
             map_check_timestamp=map_check_timestamp,
-            mapfile=(mapfile or
-                     functions.concat(literal(self.mapfile_prefix),
-                                      functions.next_value(self.mapfile_seq))),
+            mapfile=mapfile,
             is_snapshot=is_snapshot)
         r = self.conn.execute(s)
         serial, mtime, mapfile = r.fetchone()
@@ -930,7 +934,6 @@ class Node(DBWorker):
                           update_statistics_ancestors_depth=None):
         """Move the version into another cluster."""
 
-        mtime = time()
         props = self.version_get_properties(serial)
         if not props:
             return

snf-pithos-backend/pithos/backends/lib/sqlite/node.py

@@ -580,7 +580,9 @@ class Node(DBWorker):
        Otherwise, assign to the mapfile a new unique identifier.
         """
 
-        if mapfile is None:
+        if size == 0:
+            mapfile = None
+        elif mapfile is None:
             q = ("insert into mapfile_seq (dummy) values (?)")
             serial = self.execute(q, (False,)).lastrowid
             mapfile = ''.join([self.mapfile_prefix, unicode(serial)])
@@ -632,8 +634,8 @@ class Node(DBWorker):
             else:
                 cols = ("serial, node, hash, size, type, source, mtime, "
                         "muser, uuid, checksum, cluster, "
-                        "available, map_check_timestamp,"
-                        "mapfile, is_snapshot"),
+                        "available, map_check_timestamp, "
+                        "mapfile, is_snapshot")
             q = q % (cols, subq)
 
         self.execute(q, args + [cluster])
@@ -667,10 +669,10 @@ class Node(DBWorker):
             if keys:
                 cols = ','.join(k for k in keys if k in self._props)
             else:
-                cols = ("serial, node, hash, size, type, source, mtime, "
-                        "muser, uuid, checksum, cluster, "
-                        "available, map_check_timestamp,"
-                        "mapfile, is_snapshot")
+                cols = ("v.serial, v.node, v.hash, v.size, v.type, v.source, "
+                        "v.mtime, v.muser, v.uuid, v.checksum, v.cluster, "
+                        "v.available, v.map_check_timestamp,v.mapfile, "
+                        "v.is_snapshot")
             q = q % (cols, subq, "order by path" if order_by_path else "")
 
         args += [cluster]
@@ -687,7 +689,7 @@ class Node(DBWorker):
         """
 
         props = props or self._props
-        keys = keys or props.keys
+        keys = keys or props.keys()
         cols = ','.join(k for k in keys if k in props)
         q = ("select %s from versions where serial = ? ") % cols
         args = [serial]
@@ -715,7 +717,7 @@ class Node(DBWorker):
         if not props:
             return
         node = props[self.NODE]
-        size = props[self.IZE]
+        size = props[self.SIZE]
         oldcluster = props[self.CLUSTER]
         if cluster == oldcluster:
             return

snf-pithos-backend/pithos/backends/modular.py

@@ -1191,7 +1191,7 @@ class ModularBackend(BaseBackend):
         """Return the object's size and a list with partial hashes."""
         self._can_read_object(user, account, container, name)
         path, node = self._lookup_object(account, container, name)
-        props = self._get_version(node, version, keys=_propnames)
+        props = self._get_version(node, version)
         return props[self.IS_SNAPSHOT], props[self.SIZE], \
                 self._get_object_hashmap(props, update_available=True)
 
@@ -1486,8 +1486,7 @@ class ModularBackend(BaseBackend):
             nodes = [elem[2] for elem in src_names]
             # TODO: Will do another fetch of the properties
             # in duplicate version...
-            props = self._get_versions(nodes,
-                                       keys=_propnames)
+            props = self._get_versions(nodes)
 
             for prop, path, node in zip(props, paths, nodes):
                 src_version_id = prop[self.SERIAL]
@@ -1967,7 +1966,7 @@ class ModularBackend(BaseBackend):
             pre_version_id = None
             props = self.node.version_lookup(node, inf, CLUSTER_NORMAL)
             if props is not None:
-                pre_version_id = props.serial
+                pre_version_id = props[self.SERIAL]
         if pre_version_id is not None:
             self.node.version_recluster(pre_version_id, CLUSTER_HISTORY,
                                         update_statistics_ancestors_depth)