Refactors utils.load_cached_file

* adds a boolean return representing whether file was reloaded
 * ensures file is actually closed by using a context manager

Change-Id: I4d998c34caa6dde65aaf780c188778477b7f6753
This commit is contained in:
Vishvananda Ishaya 2012-01-04 18:40:46 -08:00
parent 12dade1a29
commit d383ef607a

@ -1176,18 +1176,24 @@ def sanitize_hostname(hostname):
return hostname
def read_cached_file(filename, cache_info):
"""Return the contents of a file. If the file hasn't changed since the
last invocation, a cached version will be returned.
def read_cached_file(filename, cache_info, reload_func=None):
"""Read from a file if it has been modified.
:param cache_info: dictionary to hold opaque cache.
:param reload_func: optional function to be called with data when
file is reloaded due to a modification.
:returns: data from file
"""
mtime = os.path.getmtime(filename)
if cache_info and mtime == cache_info.get('mtime', None):
return cache_info['data']
data = open(filename).read()
cache_info['data'] = data
cache_info['mtime'] = mtime
return data
if not cache_info or mtime != cache_info.get('mtime'):
with open(filename) as fap:
cache_info['data'] = fap.read()
cache_info['mtime'] = mtime
if reload_func:
reload_func(cache_info['data'])
return cache_info['data']
@contextlib.contextmanager