def BuildPatchedWpr():
shutil.copyfile(self._common_builder.original_wpr_task.path,
BuildPatchedWpr.path)
wpr_archive = wpr_backend.WprArchiveBackend(BuildPatchedWpr.path)
# Save up original response headers.
original_response_headers = {e.url: e.GetResponseHeadersDict() \
for e in wpr_archive.ListUrlEntries()}
logging.info('save up response headers for %d resources',
len(original_response_headers))
if not original_response_headers:
# TODO(gabadie): How is it possible to not even have the main resource
# in the WPR archive? Example URL can be found in:
# http://crbug.com/623966#c5
raise Exception(
'Looks like no resources were recorded in WPR during: {}'.
format(self._common_builder.original_wpr_task.name))
with open(self._original_headers_path, 'w') as file_output:
json.dump(original_response_headers, file_output)
# Patch WPR.
wpr_url_entries = wpr_archive.ListUrlEntries()
for wpr_url_entry in wpr_url_entries:
sandwich_utils.PatchWprEntryToBeCached(wpr_url_entry)
logging.info('number of patched entries: %d', len(wpr_url_entries))
wpr_archive.Persist()
def PatchWpr(wpr_archive_path):
"""Patches a WPR archive to get all resources into the HTTP cache and avoid
invalidation and revalidations.
Args:
wpr_archive_path: Path of the WPR archive to patch.
"""
# Sets the resources cache max-age to 10 years.
MAX_AGE = 10 * 365 * 24 * 60 * 60
CACHE_CONTROL = 'public, max-age={}'.format(MAX_AGE)
wpr_archive = wpr_backend.WprArchiveBackend(wpr_archive_path)
for url_entry in wpr_archive.ListUrlEntries():
response_headers = url_entry.GetResponseHeadersDict()
if 'cache-control' in response_headers and \
response_headers['cache-control'] == CACHE_CONTROL:
continue
logging.info('patching %s' % url_entry.url)
# TODO(gabadie): may need to patch Last-Modified and If-Modified-Since.
# TODO(gabadie): may need to delete ETag.
# TODO(gabadie): may need to patch Vary.
# TODO(gabadie): may need to take care of x-cache.
#
# Override the cache-control header to set the resources max age to MAX_AGE.
#
# Important note: Some resources holding sensitive information might have
# cache-control set to no-store which allow the resource to be cached but
# not cached in the file system. NoState-Prefetch is going to take care of
# this case. But in here, to simulate NoState-Prefetch, we don't have other
# choices but save absolutely all cached resources on disk so they survive
# after killing chrome for cache save, modification and push.
url_entry.SetResponseHeader('cache-control', CACHE_CONTROL)
wpr_archive.Persist()
def BuildPatchedWpr():
shutil.copyfile(self._common_builder.original_wpr_task.path,
BuildPatchedWpr.path)
wpr_archive = wpr_backend.WprArchiveBackend(BuildPatchedWpr.path)
wpr_url_entries = wpr_archive.ListUrlEntries()
for wpr_url_entry in wpr_url_entries:
sandwich_utils.PatchWprEntryToBeCached(wpr_url_entry)
logging.info('number of patched entries: %d', len(wpr_url_entries))
wpr_archive.Persist()
def BuildPatchedWpr():
common_util.EnsureParentDirectoryExists(BuildPatchedWpr.path)
shutil.copyfile(
self._common_builder.original_wpr_task.path, BuildPatchedWpr.path)
wpr_archive = wpr_backend.WprArchiveBackend(BuildPatchedWpr.path)
# Save up original response headers.
original_response_headers = {e.url: e.GetResponseHeadersDict() \
for e in wpr_archive.ListUrlEntries()}
with open(self._original_headers_path, 'w') as file_output:
json.dump(original_response_headers, file_output)
# Patch WPR.
_PatchWpr(wpr_archive)
wpr_archive.Persist()
def PatchWpr(wpr_archive_path):
"""Patches a WPR archive to get all resources into the HTTP cache and avoid
invalidation and revalidations.
Args:
wpr_archive_path: Path of the WPR archive to patch.
"""
# Sets the resources cache max-age to 10 years.
MAX_AGE = 10 * 365 * 24 * 60 * 60
CACHE_CONTROL = 'public, max-age={}'.format(MAX_AGE)
wpr_archive = wpr_backend.WprArchiveBackend(wpr_archive_path)
for url_entry in wpr_archive.ListUrlEntries():
response_headers = url_entry.GetResponseHeadersDict()
if 'cache-control' in response_headers and \
response_headers['cache-control'] == CACHE_CONTROL:
continue
logging.info('patching %s' % url_entry.url)
# TODO(gabadie): may need to patch Last-Modified and If-Modified-Since.
# TODO(gabadie): may need to delete ETag.
# TODO(gabadie): may need to take care of x-cache.
#
# Override the cache-control header to set the resources max age to MAX_AGE.
#
# Important note: Some resources holding sensitive information might have
# cache-control set to no-store which allow the resource to be cached but
# not cached in the file system. NoState-Prefetch is going to take care of
# this case. But in here, to simulate NoState-Prefetch, we don't have other
# choices but save absolutely all cached resources on disk so they survive
# after killing chrome for cache save, modification and push.
url_entry.SetResponseHeader('cache-control', CACHE_CONTROL)
# TODO(gabadie): May need to extend Vary blacklist (referer?)
#
# All of these Vary and Pragma possibilities need to be removed from
# response headers in order for Chrome to store a resource in HTTP cache and
# not to invalidate it.
#
# Note: HttpVaryData::Init() in Chrome adds an implicit 'Vary: cookie'
# header to any redirect.
# TODO(gabadie): Find a way to work around this issue.
url_entry.RemoveResponseHeaderDirectives('vary', {'*', 'cookie'})
url_entry.RemoveResponseHeaderDirectives('pragma', {'no-cache'})
wpr_archive.Persist()