def _action(self, info):
action = info["action"]
filename = info["filename"]
fullpath = path.join(self.installpath, filename)
# verify file integrity and attempt to repair if corrupted
if action == "verify":
log.info("Action: verify {0}".format(filename))
hash = info["sha1-before"]
if not sha1(fullpath) == hash:
if "full-uri" in info:
fullformat = None
if "full-format" in info:
fullformat = info["full-format"]
self._backup(filename)
log.info("Extract replacement file from {0}".format(info["full-uri"]))
with URI(info["full-uri"], package=self.package, format=fullformat,
target=fullpath):
if not sha1(fullpath) == hash:
raise Exception("Integrity check and repair failed")
else:
raise Exception("Integrity check failed with no repair")
# create a new file and verify integrity
elif action == "create":
log.info("Action: create {0}".format(filename))
hash = info["sha1-after"]
if "full-uri" in info:
fullformat = None
if "full-format" in info:
fullformat = info["full-format"]
log.info("Extract new file from {0}".format(info["full-uri"]))
with URI(info["full-uri"], package=self.package, format=fullformat,
target=fullpath):
if not sha1(fullpath) == hash:
raise Exception("Created file failed integrity check")
else:
raise Exception("Create action has no URI")
# replace file and verify replacement integrity
elif action == "replace":
log.info("Action: replace {0}".format(filename))
hash = info["sha1-after"]
if "full-uri" in info:
fullformat = None
if "full-format" in info:
fullformat = info["full-format"]
self._backup(filename)
log.info("Extract replacement file from {0}".format(info["full-uri"]))
with URI(info["full-uri"], package=self.package, format=fullformat,
target=fullpath):
if not sha1(fullpath) == hash:
raise Exception("Replacement file failed integrity check")
else:
raise Exception("Replacement action has no URI")
# delete a file with little recourse
elif action == "delete":
log.info("Action: delete {0}".format(filename))
self._backup(filename)
# intentional exception to test rollbacks
elif action == "exception":
log.warning("Action: exception")
raise Exception("Intentional exception raised")
# /shrug
else:
raise Exception("Unsupported action %s" % (action))
def apply(self, installpath, backuppath=None):
"""
Apply the manifest against the given installation path.
"""
self.installpath = installpath
manifest = self.manifest
# fetch and verify package
if "package-uri" in manifest:
packageuri = URI(manifest["package-uri"])
packagename = path.basename(packageuri["path"])
packagepath = path.join(tempfile.gettempdir(), packagename)
packageformat = None
if "package-format" in manifest:
packageformat = manifest["package-format"]
# download package file
log.info("Fetching update package from {0}".format(packageuri.uri))
packageuri.fetch(packagepath)
packageuri.close()
# integrity check
if "package-sha1" in manifest:
packagesha1 = sha1(packagepath)
if not packagesha1 == manifest["package-sha1"]:
raise Exception("Package integrity check failed")
self.package = Package(packagepath, packageformat)
# create spot for backup files
if backuppath is None:
self.backuppath = tempfile.mkdtemp(prefix="update_")
else:
self.backuppath = backuppath
if not path.isdir(self.backuppath):
log.debug("Backup path {0} does not exist; creating".format(self.backuppath))
os.mkdir(self.backuppath)
# start applying actions
try:
for info in manifest.actions:
self._action(info)
# handle update errors by rolling back
except Exception as err:
log.exception("Exception eaten; beginning rollback")
for root, dirs, files in os.walk(self.backuppath):
relpath = path.relpath(root, self.backuppath)
if relpath == ".":
relpath = ""
for filename in files:
filepath = path.join(relpath, filename)
log.info("Rolling back file %s" % (filepath))
self._restore(filepath)
log.info("Rollback completed; raising exception")
raise
# clean up
finally:
self.cleanup = False
shutil.rmtree(self.backuppath, onerror=self._onerror)
self.package.close()
os.remove(packagepath)
if self.cleanup:
return self.backuppath
def fetch(self, target=None):
parse = self.parse
# local file
if parse.scheme == "file":
self.handle = File(parse.path, "r", format=self.format)
if target:
self.handle.decompress(target)
self.handle.close()
self.handle = File(target, "r")
# package file
elif parse.scheme == "package":
if self.package is None:
raise Exception("No package specified")
filename = parse.path.lstrip("/")
self.handle = self.package.open(filename, "r", format=self.format)
if target:
self.handle.decompress(target)
self.handle.close()
self.handle = File(target, "r")
# remote http resource
elif parse.scheme in ("http", "https"):
failure = True
tries = 0
while failure:
failure = False
try:
if target:
target = path.normpath(target)
log.info("Downloading {0} to file {1}".format(self.uri, target))
downloadpath, headers = urllib.urlretrieve(self.uri)
self.handle = File(downloadpath, "r", format=self.format)
self.handle.decompress(target)
self.handle.close()
self.handle = File(target, "r")
else:
self.handle = urllib2.urlopen(self.uri)
except:
failure = True
if tries < 3:
log.info("Problem retrieving URI, retry in 3 seconds...")
log.debug(traceback.format_exception(sys.exc_type,
sys.exc_value,
sys.exc_traceback))
time.sleep(3)
else:
log.info("Failed retrieving URI")
raise
finally:
tries += 1
return self.handle
else:
raise Exception("Unsupported URI scheme {0}".format(parse.scheme))
return self.handle