From 1b2ec5f86133679c7d1111ae3b4f046777426fde Mon Sep 17 00:00:00 2001
From: Nikos Skalkotos <skalkoto@grnet.gr>
Date: Thu, 26 Jun 2014 18:15:27 +0300
Subject: [PATCH] Add Mount context manager in OSBase cls
Remove mount and unmount methods and add a mount context manager for
mounting the media file systems.
---
image_creator/os_type/__init__.py | 88 ++++++++++-------------
image_creator/os_type/freebsd.py | 2 +-
image_creator/os_type/unix.py | 2 +-
image_creator/os_type/windows/__init__.py | 33 ++-------
4 files changed, 46 insertions(+), 79 deletions(-)
diff --git a/image_creator/os_type/__init__.py b/image_creator/os_type/__init__.py
index bd3ae62..e38c135 100644
--- a/image_creator/os_type/__init__.py
+++ b/image_creator/os_type/__init__.py
@@ -208,10 +208,10 @@ class OSBase(object):
"`%s'. Reason: %s" % (key, param.error))
self.meta = {}
- self.mounted = False
# This will host the error if mount fails
self._mount_error = ""
+ self._mount_warnings = []
# Many guestfs compilations don't support scrub
self._scrub_support = True
@@ -227,27 +227,19 @@ class OSBase(object):
return
self.out.output('Running OS inspection:')
- try:
- if not self.mount(readonly=True, silent=True):
- raise FatalError("Unable to mount the media read-only")
+ with self.mount(readonly=True, silent=True):
self._do_inspect()
- finally:
- self.umount(silent=True)
-
self.out.output()
def collect_metadata(self):
"""Collect metadata about the OS"""
- try:
- if not self.mount(readonly=True, silent=True):
- raise FatalError("Unable to mount the media read-only")
- self.out.output('Collecting image metadata ...', False)
+ self.out.output('Collecting image metadata ...', False)
+
+ with self.mount(readonly=True, silent=True):
self._do_collect_metadata()
- self.out.success('done')
- finally:
- self.umount(silent=True)
+ self.out.success('done')
self.out.output()
def list_syspreps(self):
@@ -352,12 +344,7 @@ class OSBase(object):
"System preparation is disabled for unsupported media")
return
- try:
- if not self.mount(readonly=False):
- msg = "Unable to mount the media read-write. Reason: %s" % \
- self._mount_error
- raise FatalError(msg)
-
+ with self.mount():
enabled = [task for task in self.list_syspreps() if task.enabled]
size = len(enabled)
@@ -367,39 +354,40 @@ class OSBase(object):
self.out.output(('(%d/%d)' % (cnt, size)).ljust(7), False)
task()
setattr(task.im_func, 'executed', True)
- finally:
- self.umount()
self.out.output()
- def mount(self, readonly=False, silent=False):
- """Mount image."""
-
- if getattr(self, "mounted", False):
- return True
-
- mount_type = 'read-only' if readonly else 'read-write'
- if not silent:
- self.out.output("Mounting the media %s ..." % mount_type, False)
-
- self._mount_error = ""
- if not self._do_mount(readonly):
- return False
-
- self.mounted = True
- if not silent:
- self.out.success('done')
- return True
-
- def umount(self, silent=False):
- """Umount all mounted file systems."""
-
- if not silent:
- self.out.output("Umounting the media ...", False)
- self.image.g.umount_all()
- self.mounted = False
- if not silent:
- self.out.success('done')
+ def mount(self, readonly=False, silent=False, fatal=True):
+ """Returns a context manager for mounting an image"""
+
+ parent = self
+ output = lambda msg='', nl=True: None if silent else self.out.output
+ success = lambda msg='', nl=True: None if silent else self.out.success
+ warn = lambda msg='', nl=True: None if silent else self.out.warn
+
+ class Mount:
+ """The Mount context manager"""
+ def __enter__(self):
+ mount_type = 'read-only' if readonly else 'read-write'
+ output("Mounting the media %s ..." % mount_type, False)
+
+ parent._mount_error = ""
+ del parent._mount_warnings[:]
+
+ if not parent._do_mount(readonly) and fatal:
+ msg = "Unable to mount the media %s. Reason: %s" % \
+ (mount_type, parent._mount_error)
+ raise FatalError(msg)
+ for warning in parent._mount_warnings:
+ warn(warning)
+ success('done')
+
+ def __exit__(self, exc_type, exc_value, traceback):
+ output("Umounting the media ...", False)
+ parent.image.g.umount_all()
+ success('done')
+
+ return Mount()
def check_version(self, major, minor):
"""Checks the OS version against the one specified by the major, minor
diff --git a/image_creator/os_type/freebsd.py b/image_creator/os_type/freebsd.py
index d8df923..426e974 100644
--- a/image_creator/os_type/freebsd.py
+++ b/image_creator/os_type/freebsd.py
@@ -121,7 +121,7 @@ class Freebsd(Unix):
self._mount_error = str(msg)
return False
else:
- self.out.warn('%s (ignored)' % msg)
+ self._mount_warnings.append('%s (ignored)' % msg)
return True
diff --git a/image_creator/os_type/unix.py b/image_creator/os_type/unix.py
index 00ede28..ac5e342 100644
--- a/image_creator/os_type/unix.py
+++ b/image_creator/os_type/unix.py
@@ -66,7 +66,7 @@ class Unix(OSBase):
self._mount_error = str(msg)
return False
else:
- self.out.warn('%s (ignored)' % msg)
+ self._mount_warnings.append('%s (ignored)' % msg)
return True
diff --git a/image_creator/os_type/windows/__init__.py b/image_creator/os_type/windows/__init__.py
index f93e0b5..d02f33a 100644
--- a/image_creator/os_type/windows/__init__.py
+++ b/image_creator/os_type/windows/__init__.py
@@ -173,14 +173,11 @@ class Windows(OSBase):
self.registry = Registry(self.image.g, self.root)
# If the image is already sysprepped we cannot further customize it
- self.mount(readonly=True, silent=True)
- try:
+ with self.mount(readonly=True, silent=True):
self.out.output("Checking media state ...", False)
self.sysprepped = self.registry.get_setup_state() > 0
self.virtio_state = self._virtio_state()
self.out.success("done")
- finally:
- self.umount(silent=True)
# If the image is sysprepped no driver mappings will be present.
self.systemdrive = None
@@ -374,12 +371,8 @@ class Windows(OSBase):
shutdown_timeout = self.sysprep_params['shutdown_timeout'].value
self.out.output("Preparing media for boot ...", False)
- try:
- if not self.mount(readonly=False, silent=True):
- msg = "Unable to mount the media read-write. Reason: %s" % \
- self._mount_error
- raise FatalError(msg)
+ with self.mount(readonly=False, silent=True):
v_val = self.registry.reset_passwd(admin)
disabled_uac = self.registry.update_uac_remote_setting(1)
token = self._add_boot_scripts()
@@ -394,8 +387,6 @@ class Windows(OSBase):
except RuntimeError:
pass
- finally:
- self.umount(silent=True)
self.out.success('done')
self.image.disable_guestfs()
@@ -433,8 +424,7 @@ class Windows(OSBase):
self.image.enable_guestfs()
self.out.output("Reverting media boot preparations ...", False)
- self.mount(readonly=False, silent=True)
- try:
+ with self.mount(readonly=False, silent=True, fatal=False):
if disabled_uac:
self.registry.update_uac_remote_setting(0)
@@ -444,8 +434,6 @@ class Windows(OSBase):
self.registry.reset_passwd(admin, v_val)
self.registry.update_firewalls(*firewall_states)
- finally:
- self.umount(silent=True)
self.out.success("done")
def _exec_sysprep_tasks(self):
@@ -618,11 +606,7 @@ class Windows(OSBase):
self.out.output('Installing virtio drivers...', False)
- try:
- if not self.mount(readonly=False, silent=True):
- msg = "Unable to mount the media read-write. Reason: %s" % \
- self._mount_error
- raise FatalError(msg)
+ with self.mount(readonly=False, silent=True):
admin = self.sysprep_params['admin'].value
v_val = self.registry.reset_passwd(admin)
@@ -646,20 +630,15 @@ class Windows(OSBase):
self.registry.runonce({'InstallDrivers': cmd})
- finally:
- self.umount(silent=True)
-
try:
self.vm.start()
self.out.success("started (console on VNC display: %d)" %
self.vm.display)
finally:
self.vm.stop(6000)
- try:
- self.mount(readonly=True, silent=True)
+
+ with self.mount(readonly=True, silent=True):
self.virtio_state = self._virtio_state()
- finally:
- self.umount(silent=True)
def _install_viostor_driver(self, dirname):
--
GitLab