def read_transaction(self, key):
"""Get a read transaction on a file cache item.
Returns a ReadTransaction context manager and opens the cache file for
reading. You can use it like this:
with file_cache_object.read_transaction(key) as cache_file:
cache_file.read()
"""
return ReadTransaction(self._get_lock(key),
acquire=lambda: open(self.cache_path(key)))
def read_transaction(self):
"""Get a read lock context manager for use in a `with` block."""
return ReadTransaction(self.lock, self._read)
def read_transaction(self, timeout=_db_lock_timeout):
"""Get a read lock context manager for use in a `with` block."""
return ReadTransaction(self.lock, self._read, timeout=timeout)