Improve logging and raising DiskFileNoSpace

This commit only improves logging whenever ENOSPC (No space on disk)
or EDQUOT (Quota limit exceeded) is returned by glusterfs

Also, added methods to:
- get filename from file descriptor
- log with rate limit

Caveat: Although raising DiskFileNoSpace results in object-server
returning HTTPInsufficientStorage[507] correctly, the swift proxy-server
invokes "best_response" method that returns [503] to the user.

When write-behind translator is turned on in glusterfs, it may set
errno to EIO instead of ENOSPC/EDQUOT. This is documented in BZ 986812

BUG: 985862, 985253, 1020724
Change-Id: Ib0c5e41c11a8cdccc2077f71c31d8a23229452bb
Signed-off-by: Prashanth Pai <ppai@redhat.com>
Reviewed-on: http://review.gluster.org/6199
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>
Reviewed-on: http://review.gluster.org/6269

1 files changed, 23 insertions, 0 deletions

diff --git a/test/unit/common/test_utils.py b/test/unit/common/test_utils.py
index 4d345da..2582558 100644
--- a/test/unit/common/test_utils.py
+++ b/test/unit/common/test_utils.py
@@ -28,6 +28,7 @@ from collections import defaultdict
 from mock import patch
 from gluster.swift.common import utils, Glusterfs
 from gluster.swift.common.exceptions import GlusterFileSystemOSError
+from swift.common.exceptions import DiskFileNoSpace
 
 #
 # Somewhat hacky way of emulating the operation of xattr calls. They are made
@@ -169,6 +170,28 @@ class TestUtils(unittest.TestCase):
         else:
             self.fail("Expected an IOError exception on write")
 
+    def test_write_metadata_space_err(self):
+
+        def _mock_xattr_setattr(item, name, value):
+            raise IOError(errno.ENOSPC, os.strerror(errno.ENOSPC))
+
+        with patch('xattr.setxattr', _mock_xattr_setattr):
+            path = "/tmp/foo/w"
+            orig_d = {'bar': 'foo'}
+            try:
+                utils.write_metadata(path, orig_d)
+            except DiskFileNoSpace:
+                pass
+            else:
+                self.fail("Expected DiskFileNoSpace exception")
+            fd = 0
+            try:
+                utils.write_metadata(fd, orig_d)
+            except DiskFileNoSpace:
+                pass
+            else:
+                self.fail("Expected DiskFileNoSpace exception")
+
     def test_write_metadata_multiple(self):
         # At 64 KB an xattr key/value pair, this should generate three keys.
         path = "/tmp/foo/w"