def unescape_encoded_uri_component(escaped_string: str) -> str:
"""Unescape a string that is encoded with encodeURIComponent.
Args:
escaped_string: str. String that is encoded with encodeURIComponent.
Returns:
str. Decoded string that was initially encoded with encodeURIComponent.
"""
return python_utils.urllib_unquote(escaped_string)
def get(self, page_context, page_identifier, asset_type, encoded_filename):
"""Returns an asset file.
Args:
page_context: str. The context of the page where the asset is
required.
page_identifier: str. The unique identifier for the particular
context. Valid page_context: page_identifier pairs:
exploration: exp_id
story: story_id
topic: topic_id
skill: skill_id
subtopic: topic_name of the topic that it is part of.
asset_type: str. Type of the asset, either image or audio.
encoded_filename: str. The asset filename. This
string is encoded in the frontend using encodeURIComponent().
"""
if not constants.EMULATOR_MODE:
raise self.PageNotFoundException
try:
filename = python_utils.urllib_unquote(encoded_filename)
file_format = filename[(filename.rfind('.') + 1):]
# If the following is not cast to str, an error occurs in the wsgi
# library because unicode gets used.
content_type = (
'image/svg+xml' if file_format == 'svg' else '%s/%s' % (
asset_type, file_format))
self.response.headers['Content-Type'] = content_type
if page_context not in self._SUPPORTED_PAGE_CONTEXTS:
raise self.InvalidInputException
fs = fs_domain.AbstractFileSystem(
fs_domain.GcsFileSystem(page_context, page_identifier))
raw = fs.get('%s/%s' % (asset_type, filename))
self.response.cache_control.no_cache = None
self.response.cache_control.public = True
self.response.cache_control.max_age = 600
self.response.body_file = io.BytesIO(raw)
except Exception as e:
logging.exception(
'File not found: %s. %s' % (encoded_filename, e))
raise self.PageNotFoundException
def convert_png_data_url_to_binary(image_data_url: str) -> bytes:
"""Converts a PNG base64 data URL to a PNG binary data.
Args:
image_data_url: str. A string that is to be interpreted as a PNG
data URL.
Returns:
bytes. Binary content of the PNG created from the data URL.
Raises:
Exception. The given string does not represent a PNG data URL.
"""
if image_data_url.startswith(PNG_DATA_URL_PREFIX):
return base64.b64decode(
python_utils.urllib_unquote(
image_data_url[len(PNG_DATA_URL_PREFIX):]))
else:
raise Exception('The given string does not represent a PNG data URL.')
def test_urllib_unquote(self):
response = python_utils.urllib_unquote('/El%20Ni%C3%B1o/')
self.assertEqual(response, '/El Niño/')