def __call__(self, environ, start_response):
"""Method that is called by the running WSGI server.
You should NOT be calling this method yourself under normal circumstances.
"""
response_headers = {}
response_status = 0
iterable = None
req = Request(environ)
def _start_response(_status, _response_headers, *args):
write = start_response(_status, _response_headers, *args)
# Populate response info (headers & status)
nonlocal response_headers, response_status
response_headers = _response_headers
response_status = _status
return write
try:
req.rm_start_dt = str(datetime.datetime.now())
req.rm_start_ts = int(time.time() * 1000)
if req.method == "POST":
# The next 4 lines are a workaround for a serious shortcoming in the
# WSGI spec.
#
# The data can only be read once, after which the socket is exhausted
# and cannot be read again. As such, we read the data and then
# repopulate the variable so that it can be used by other code down the
# pipeline.
#
# For more info: https://stackoverflow.com/a/13106009/643951
# the environment variable CONTENT_LENGTH may be empty or missing
try:
content_length = int(environ.get("CONTENT_LENGTH", 0))
except (ValueError):
content_length = 0
content_body = environ["wsgi.input"].read(content_length)
# guarding check to close stream
if hasattr(environ["CONTENT_LENGTH"], "close"):
environ["wsgi.input"].close()
environ["wsgi.input"] = io.BytesIO(content_body)
req.rm_content_length = content_length
req.rm_body = content_body
iterable = self.app(environ, _start_response)
for data in iterable:
res_ctype = ""
res_clength = 0
htype = next(
(h for h in response_headers if h[0] == "Content-Type"),
None)
hlength = next(
(h for h in response_headers if h[0] == "Content-Length"),
None)
if htype and hlength:
res_ctype = htype[1]
res_clength = int(hlength[1])
# Populate response body
res = ResponseInfoWrapper(
response_headers,
response_status,
res_ctype,
res_clength,
data.decode("utf-8"),
)
# Send off data to be queued (and processed) by ReadMe if allowed
if self.config.ALLOWED_HTTP_HOSTS:
if environ["HTTP_HOST"] in self.config.ALLOWED_HTTP_HOSTS:
self.metrics_core.process(req, res)
else:
# If the allowed_http_hosts has not been set (None by default), send off the data to be queued
self.metrics_core.process(req, res)
yield data
finally:
# Undocumented in WSGI spec but the iterable has to be closed
if hasattr(iterable, "close"):
iterable.close()
