commit de0ed93bda6323335cf84bc3d33e3aa848786a65
author Michael Mortensen <mmortensen@google.com> Thu Jul 30 10:53:30 2020 -0600
committer Commit Bot <commit-bot@chromium.org> Fri Jul 31 13:17:06 2020 +0000
tree c0a96a7661b4a565a682332157acff88551b3b52
parent aec59350c64049e256c3124979c2bcb38f46345f

BuildAPI: Improve exception processing in service.UnmountPath.

These are post-submit changes suggested on https://crrev.com/c/2327231/2.

BUG=chromium:1095661
TEST=run_tests

Change-Id: I483ee37feb324e26157d3a121763b5af50b045b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/2329394
Tested-by: Michael Mortensen <mmortensen@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Michael Mortensen <mmortensen@google.com>

service/sdk.py

diff --git a/service/sdk.py b/service/sdk.py
index ef9aef7..1713be8 100644
--- a/service/sdk.py
+++ b/service/sdk.py
@@ -25,9 +25,17 @@
 class UnmountError(Error):
   """An error raised when unmount fails."""
 
-  def __init__(self, message):
-    self.message = message
-    super(UnmountError, self).__init__(message)
+  def __init__(self, path, cmd_error=None, fs_debug=None):
+    super(UnmountError, self).__init__(path, cmd_error, fs_debug)
+    self.path = path
+    self.cmd_error = cmd_error
+    self.fs_debug = fs_debug
+
+  def __str__(self):
+    return (f'Umount failed: {self.cmd_error.result.stdout}.\n'
+            f'fuser output={self.fs_debug.fuser}\n'
+            f'lsof output={self.fs_debug.lsof}\n'
+            f'ps output={self.fs_debug.ps}\n')
 
 
 class CreateArguments(object):
@@ -232,9 +240,7 @@
     osutils.UmountTree(path.path)
   except cros_build_lib.RunCommandError as e:
     fs_debug = cros_sdk_lib.GetFileSystemDebug(path.path, run_ps=True)
-    msg = (f'Umount failed: {e.result.error}.\nfuser output={fs_debug.fuser}\n'
-           f'lsof output={fs_debug.lsof}\nps output=fs_debug.ps\n')
-    raise UnmountError(msg)
+    raise UnmountError(path.path, e, fs_debug)
 
 
 def GetChrootVersion(chroot_path=None):

service/sdk_unittest.py

diff --git a/service/sdk_unittest.py b/service/sdk_unittest.py
index d781e2f..ed3f350 100644
--- a/service/sdk_unittest.py
+++ b/service/sdk_unittest.py
@@ -95,7 +95,10 @@
                          'umount failure'))
     with self.assertRaises(sdk.UnmountError) as unmount_assert:
       sdk.UnmountPath(path_proto)
-    self.assertIn('Umount failed:', unmount_assert.exception.message)
+    # Unpack the underlying (thrown) exception from the assertRaises context
+    # manager exception attribute.
+    unmount_exception = unmount_assert.exception
+    self.assertIn('Umount failed:', str(unmount_exception))
 
 
 class CreateTest(cros_test_lib.RunCommandTempDirTestCase):