diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/asgiref/wsgi.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/asgiref/wsgi.py | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/asgiref/wsgi.py b/.venv/lib/python3.12/site-packages/asgiref/wsgi.py new file mode 100644 index 00000000..65af4279 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/asgiref/wsgi.py @@ -0,0 +1,166 @@ +from io import BytesIO +from tempfile import SpooledTemporaryFile + +from asgiref.sync import AsyncToSync, sync_to_async + + +class WsgiToAsgi: + """ + Wraps a WSGI application to make it into an ASGI application. + """ + + def __init__(self, wsgi_application): + self.wsgi_application = wsgi_application + + async def __call__(self, scope, receive, send): + """ + ASGI application instantiation point. + We return a new WsgiToAsgiInstance here with the WSGI app + and the scope, ready to respond when it is __call__ed. + """ + await WsgiToAsgiInstance(self.wsgi_application)(scope, receive, send) + + +class WsgiToAsgiInstance: + """ + Per-socket instance of a wrapped WSGI application + """ + + def __init__(self, wsgi_application): + self.wsgi_application = wsgi_application + self.response_started = False + self.response_content_length = None + + async def __call__(self, scope, receive, send): + if scope["type"] != "http": + raise ValueError("WSGI wrapper received a non-HTTP scope") + self.scope = scope + with SpooledTemporaryFile(max_size=65536) as body: + # Alright, wait for the http.request messages + while True: + message = await receive() + if message["type"] != "http.request": + raise ValueError("WSGI wrapper received a non-HTTP-request message") + body.write(message.get("body", b"")) + if not message.get("more_body"): + break + body.seek(0) + # Wrap send so it can be called from the subthread + self.sync_send = AsyncToSync(send) + # Call the WSGI app + await self.run_wsgi_app(body) + + def build_environ(self, scope, body): + """ + Builds a scope and request body into a WSGI environ object. + """ + script_name = scope.get("root_path", "").encode("utf8").decode("latin1") + path_info = scope["path"].encode("utf8").decode("latin1") + if path_info.startswith(script_name): + path_info = path_info[len(script_name) :] + environ = { + "REQUEST_METHOD": scope["method"], + "SCRIPT_NAME": script_name, + "PATH_INFO": path_info, + "QUERY_STRING": scope["query_string"].decode("ascii"), + "SERVER_PROTOCOL": "HTTP/%s" % scope["http_version"], + "wsgi.version": (1, 0), + "wsgi.url_scheme": scope.get("scheme", "http"), + "wsgi.input": body, + "wsgi.errors": BytesIO(), + "wsgi.multithread": True, + "wsgi.multiprocess": True, + "wsgi.run_once": False, + } + # Get server name and port - required in WSGI, not in ASGI + if "server" in scope: + environ["SERVER_NAME"] = scope["server"][0] + environ["SERVER_PORT"] = str(scope["server"][1]) + else: + environ["SERVER_NAME"] = "localhost" + environ["SERVER_PORT"] = "80" + + if scope.get("client") is not None: + environ["REMOTE_ADDR"] = scope["client"][0] + + # Go through headers and make them into environ entries + for name, value in self.scope.get("headers", []): + name = name.decode("latin1") + if name == "content-length": + corrected_name = "CONTENT_LENGTH" + elif name == "content-type": + corrected_name = "CONTENT_TYPE" + else: + corrected_name = "HTTP_%s" % name.upper().replace("-", "_") + # HTTPbis say only ASCII chars are allowed in headers, but we latin1 just in case + value = value.decode("latin1") + if corrected_name in environ: + value = environ[corrected_name] + "," + value + environ[corrected_name] = value + return environ + + def start_response(self, status, response_headers, exc_info=None): + """ + WSGI start_response callable. + """ + # Don't allow re-calling once response has begun + if self.response_started: + raise exc_info[1].with_traceback(exc_info[2]) + # Don't allow re-calling without exc_info + if hasattr(self, "response_start") and exc_info is None: + raise ValueError( + "You cannot call start_response a second time without exc_info" + ) + # Extract status code + status_code, _ = status.split(" ", 1) + status_code = int(status_code) + # Extract headers + headers = [ + (name.lower().encode("ascii"), value.encode("ascii")) + for name, value in response_headers + ] + # Extract content-length + self.response_content_length = None + for name, value in response_headers: + if name.lower() == "content-length": + self.response_content_length = int(value) + # Build and send response start message. + self.response_start = { + "type": "http.response.start", + "status": status_code, + "headers": headers, + } + + @sync_to_async + def run_wsgi_app(self, body): + """ + Called in a subthread to run the WSGI app. We encapsulate like + this so that the start_response callable is called in the same thread. + """ + # Translate the scope and incoming request body into a WSGI environ + environ = self.build_environ(self.scope, body) + # Run the WSGI app + bytes_sent = 0 + for output in self.wsgi_application(environ, self.start_response): + # If this is the first response, include the response headers + if not self.response_started: + self.response_started = True + self.sync_send(self.response_start) + # If the application supplies a Content-Length header + if self.response_content_length is not None: + # The server should not transmit more bytes to the client than the header allows + bytes_allowed = self.response_content_length - bytes_sent + if len(output) > bytes_allowed: + output = output[:bytes_allowed] + self.sync_send( + {"type": "http.response.body", "body": output, "more_body": True} + ) + bytes_sent += len(output) + # The server should stop iterating over the response when enough data has been sent + if bytes_sent == self.response_content_length: + break + # Close connection + if not self.response_started: + self.response_started = True + self.sync_send(self.response_start) + self.sync_send({"type": "http.response.body"}) |