async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `http` events.
"""
message_type = message["type"]
self.logger.info("%s: '%s' event received from application.",
self.state, message_type)
if (self.state is HTTPCycleState.REQUEST
and message_type == "http.response.start"):
self.response["statusCode"] = message["status"]
headers: typing.Dict[str, str] = {}
multi_value_headers: typing.Dict[str, typing.List[str]] = {}
for key, value in message.get("headers", []):
lower_key = key.decode().lower()
if lower_key in multi_value_headers:
multi_value_headers[lower_key].append(value.decode())
elif lower_key in headers:
multi_value_headers[lower_key] = [
headers.pop(lower_key),
value.decode(),
]
else:
headers[lower_key] = value.decode()
self.response["headers"] = headers
if multi_value_headers:
self.response["multiValueHeaders"] = multi_value_headers
self.state = HTTPCycleState.RESPONSE
elif (self.state is HTTPCycleState.RESPONSE
and message_type == "http.response.body"):
body = message.get("body", b"")
more_body = message.get("more_body", False)
# The body must be completely read before returning the response.
self.body += body
if not more_body:
body = self.body
# Check if a binary response should be returned based on the mime type
# or content encoding.
mimetype, _ = cgi.parse_header(self.response["headers"].get(
"content-type", "text/plain"))
if (mimetype not in self.text_mime_types
and not mimetype.startswith("text/")
) or self.response["headers"].get("content-encoding") in [
"gzip", "br"
]:
body = base64.b64encode(body)
self.response["isBase64Encoded"] = True
self.response["body"] = body.decode()
self.state = HTTPCycleState.COMPLETE
await self.app_queue.put({"type": "http.disconnect"})
else:
raise UnexpectedMessage(
f"{self.state}: Unexpected '{message_type}' event received.")
async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `websocket` events.
"""
message_type = message["type"]
self.logger.info(
"%s: '%s' event received from application.", self.state, message_type
)
if self.state is WebSocketCycleState.HANDSHAKE and message_type in (
"websocket.accept",
"websocket.close",
):
# API Gateway handles the WebSocket client handshake in the connect event,
# and it cannot be negotiated by the application directly. The handshake
# behaviour is simulated to allow the application to accept or reject the
# the client connection. This process does not support subprotocols.
if message_type == "websocket.accept":
await self.app_queue.put(
{"type": "websocket.receive", "bytes": None, "text": self.body}
)
elif message_type == "websocket.close":
self.state = WebSocketCycleState.CLOSED
raise WebSocketClosed
elif (
self.state is WebSocketCycleState.RESPONSE
and message_type == "websocket.send"
):
# Message data sent from the application is posted to the WebSocket client
# in API Gateway using an API call.
message_text = message.get("text", "")
self.websocket.post_to_connection(message_text.encode())
await self.app_queue.put({"type": "websocket.disconnect", "code": "1000"})
elif (
self.state is WebSocketCycleState.DISCONNECTING
and message_type == "websocket.close"
):
# ASGI connection is closing, however the WebSocket client in API Gateway
# will persist and be used in future application ASGI connections until the
# client disconnects or the application rejects a handshake.
self.state = WebSocketCycleState.CLOSED
else:
raise UnexpectedMessage(
f"{self.state}: Unexpected '{message_type}' event received."
)
async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `lifespan` events.
"""
message_type = message["type"]
self.logger.info("%s: '%s' event received from application.",
self.state, message_type)
if self.state is LifespanCycleState.CONNECTING:
if self.lifespan == "on":
raise LifespanFailure(
"Lifespan connection failed during startup and lifespan is 'on'."
)
# If a message is sent before the startup event is received by the
# application, then assume that lifespan is unsupported.
self.state = LifespanCycleState.UNSUPPORTED
raise LifespanUnsupported("Lifespan protocol appears unsupported.")
if message_type not in (
"lifespan.startup.complete",
"lifespan.shutdown.complete",
"lifespan.startup.failed",
"lifespan.shutdown.failed",
):
self.state = LifespanCycleState.FAILED
raise UnexpectedMessage(
f"Unexpected '{message_type}' event received.")
if self.state is LifespanCycleState.STARTUP:
if message_type == "lifespan.startup.complete":
self.startup_event.set()
elif message_type == "lifespan.startup.failed":
self.state = LifespanCycleState.FAILED
self.startup_event.set()
message = message.get("message", "")
raise LifespanFailure(f"Lifespan startup failure. {message}")
elif self.state is LifespanCycleState.SHUTDOWN:
if message_type == "lifespan.shutdown.complete":
self.shutdown_event.set()
elif message_type == "lifespan.shutdown.failed":
self.state = LifespanCycleState.FAILED
self.shutdown_event.set()
message = message.get("message", "")
raise LifespanFailure(f"Lifespan shutdown failure. {message}")
async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `http` events.
"""
message_type = message["type"]
self.logger.info("%s: '%s' event received from application.",
self.state, message_type)
if (self.state is HTTPCycleState.REQUEST
and message_type == "http.response.start"):
self.response["statusCode"] = message["status"]
self.response["headers"] = {
k.decode().lower(): v.decode()
for k, v in message.get("headers", [])
}
self.state = HTTPCycleState.RESPONSE
elif (self.state is HTTPCycleState.RESPONSE
and message_type == "http.response.body"):
body = message.get("body", b"")
more_body = message.get("more_body", False)
# The body must be completely read before returning the response.
self.body += body
if not more_body:
body = self.body
mimetype, _ = cgi.parse_header(self.response["headers"].get(
"content-type", "text/plain"))
# Check if a binary response should be returned based on the mime type
# or content encoding.
if (mimetype not in self.text_mime_types
and not mimetype.startswith("text/")) or self.response[
"headers"].get("content-encoding") == "gzip":
body = base64.b64encode(body)
self.response["isBase64Encoded"] = True
self.response["body"] = body.decode()
self.state = HTTPCycleState.COMPLETE
await self.app_queue.put({"type": "http.disconnect"})
else:
raise UnexpectedMessage(
f"{self.state}: Unexpected '{message_type}' event received.")
async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `http` events.
"""
message_type = message["type"]
self.logger.info("%s: '%s' event received from application.",
self.state, message_type)
if (self.state is HTTPCycleState.REQUEST
and message_type == "http.response.start"):
self.response["statusCode"] = message["status"]
headers: typing.Dict[str, str] = {}
multi_value_headers: typing.Dict[str, typing.List[str]] = {}
cookies: typing.List[str] = []
event = self.scope["aws.event"]
# ELB
if "elb" in event["requestContext"]:
for key, value in message.get("headers", []):
lower_key = key.decode().lower()
if lower_key in multi_value_headers:
multi_value_headers[lower_key].append(value.decode())
else:
multi_value_headers[lower_key] = [value.decode()]
if "multiValueHeaders" not in event:
# If there are multiple occurrences of headers, create case-mutated
# variations: https://github.com/logandk/serverless-wsgi/issues/11
for key, values in multi_value_headers.items():
if len(values) > 1:
for value, cased_key in zip(
values, all_casings(key)):
headers[cased_key] = value
elif len(values) == 1:
headers[key] = values[0]
multi_value_headers = {}
# API Gateway
else:
for key, value in message.get("headers", []):
lower_key = key.decode().lower()
if event.get(
"version") == "2.0" and lower_key == "set-cookie":
cookies.append(value.decode())
elif lower_key in multi_value_headers:
multi_value_headers[lower_key].append(value.decode())
elif lower_key in headers:
multi_value_headers[lower_key] = [
headers.pop(lower_key),
value.decode(),
]
else:
headers[lower_key] = value.decode()
self.response["headers"] = headers
if multi_value_headers:
self.response["multiValueHeaders"] = multi_value_headers
if cookies:
self.response["cookies"] = cookies
self.state = HTTPCycleState.RESPONSE
elif (self.state is HTTPCycleState.RESPONSE
and message_type == "http.response.body"):
body = message.get("body", b"")
more_body = message.get("more_body", False)
# The body must be completely read before returning the response.
self.body.write(body)
if not more_body:
body = self.body.getvalue()
self.body.close()
# Check if a binary response should be returned based on the mime type
# or content encoding.
mimetype, _ = cgi.parse_header(self.response["headers"].get(
"content-type", "text/plain"))
if (mimetype not in self.text_mime_types
and not mimetype.startswith("text/")
) or self.response["headers"].get("content-encoding") in [
"gzip", "br"
]:
body = base64.b64encode(body)
self.response["isBase64Encoded"] = True
self.response["body"] = body.decode()
self.state = HTTPCycleState.COMPLETE
await self.app_queue.put({"type": "http.disconnect"})
else:
raise UnexpectedMessage(
f"{self.state}: Unexpected '{message_type}' event received.")