def check_case_insensitive(self):
"""
Check for server case-insensivity and
This function must be called with an established connection and
with write permissions (like synchronize_times).
"""
helper_name = "__CachingFtpHost_Helper__"
try:
self.mkdir(helper_name)
self.lstat(helper_name) # exception if mkdir failed
try:
# if the server is case-insensitive, this will fail
file = self.mkdir(helper_name.lower())
except PermanentError:
self.logger.warning("Server is case-insensitive")
self.path = CaseInsPath(self)
self._stat = CaseInsStat(self)
self.cache.invalidate_all()
else:
self.logger.info("Server is case-sensitive")
finally:
self.rmdir(helper_name)
class CachingFTPHost(FTPHost, LoggingClass):
"""
This class is like ftputil.FTPHost, except that
the working directory and directory contents are cached.
This may speed up FTP operations significantly, especially
when traversing trees and looking for stat() like information.
However, cached information may be wrong in some cases.
It is recommended to call host.invalidate_dir(<path>) after
closing the ftp_file object associated with <path>.
Constructor keywords "expire" and "size" are the same as for
simplecache.Cache.
Besides, this class adds a method check_case_insensitive() to cope
with FTP servers that don't distinguish file names by case.
"""
def __init__(self, *args, **kwargs):
kw = {}
if "expire" in kwargs:
kw["expire"] = kwargs["expire"]
del kwargs["expire"]
if "size" in kwargs:
kw["size"] = kwargs["size"]
del kwargs["size"]
self.cache = Cache(**kw)
FTPHost.__init__(self, *args, **kwargs)
self.CWD = None
self.setcwd()
def check_case_insensitive(self):
"""
Check for server case-insensivity and
This function must be called with an established connection and
with write permissions (like synchronize_times).
"""
helper_name = "__CachingFtpHost_Helper__"
try:
self.mkdir(helper_name)
self.lstat(helper_name) # exception if mkdir failed
try:
# if the server is case-insensitive, this will fail
file = self.mkdir(helper_name.lower())
except PermanentError:
self.logger.warning("Server is case-insensitive")
self.path = CaseInsPath(self)
self._stat = CaseInsStat(self)
self.cache.invalidate_all()
else:
self.logger.info("Server is case-sensitive")
finally:
self.rmdir(helper_name)
def getcwd(self):
"""
Return cached working directory.
"""
return self.CWD
def setcwd(self):
"""
Update cached working directory.
"""
self.CWD = self.path.normpath(FTPHost.getcwd(self))
self.logger.info("New cwd: %s" % self.CWD)
def chdir(self, path):
FTPHost.chdir(self, path)
self.setcwd()
def _dir(self, path):
path = self.path.normcase(path)
try:
lines = self.cache[path]
except KeyError:
self.logger.debug("cache miss: %s" % path)
lines = FTPHost._dir(self, path)
self.cache[path] = lines
else:
self.logger.debug("cache hit: %s" % path)
return lines
def _invalidate_dir(self, path):
self.logger.debug("invalidating cache for %s" % path)
self.cache.invalidate(
self.path.normcase(
self.path.dirname(self.path.abspath(path))))
def file(self, path, mode='r'):
path = self.path.abspath(path)
ret = FTPHost.file(self, path, mode)
if 'w' in mode:
self._invalidate_dir(path)
return ret
def mkdir(self, path, mode=None):
path = self.path.abspath(path)
FTPHost.mkdir(self, path, mode)
self._invalidate_dir(path)
def rmdir(self, path):
FTPHost.rmdir(self, path)
self.cache.invalidate(self.path.normcase(
self.path.abspath(path)))
self._invalidate_dir(path)
def remove(self, path):
FTPHost.remove(self, path)
self._invalidate_dir(path)
def rename(self, source, target):
FTPHost.rename(self, source, target)
self._invalidate_dir(source)
self._invalidate_dir(target)
