# SPDX-License-Identifier: AGPL-3.0-or-later # lint: pylint # pylint: disable=missing-module-docstring, missing-function-docstring, global-statement import asyncio import logging import threading import httpcore import httpx from httpx_socks import AsyncProxyTransport from python_socks import ( parse_proxy_url, ProxyConnectionError, ProxyTimeoutError, ProxyError ) from searx import logger # Optional uvloop (support Python 3.6) try: import uvloop except ImportError: pass else: uvloop.install() logger = logger.getChild('searx.http.client') LOOP = None SSLCONTEXTS = {} TRANSPORT_KWARGS = { 'backend': 'asyncio', 'trust_env': False, } # pylint: disable=protected-access async def close_connections_for_url( connection_pool: httpcore.AsyncConnectionPool, url: httpcore._utils.URL ): origin = httpcore._utils.url_to_origin(url) logger.debug('Drop connections for %r', origin) connections_to_close = connection_pool._connections_for_origin(origin) for connection in connections_to_close: await connection_pool._remove_from_pool(connection) try: await connection.aclose() except httpcore.NetworkError as e: logger.warning('Error closing an existing connection', exc_info=e) # pylint: enable=protected-access def get_sslcontexts(proxy_url=None, cert=None, verify=True, trust_env=True, http2=False): global SSLCONTEXTS key = (proxy_url, cert, verify, trust_env, http2) if key not in SSLCONTEXTS: SSLCONTEXTS[key] = httpx.create_ssl_context(cert, verify, trust_env, http2) return SSLCONTEXTS[key] class AsyncHTTPTransportNoHttp(httpcore.AsyncHTTPTransport): """Block HTTP request""" async def arequest(self, method, url, headers=None, stream=None, ext=None): raise httpcore.UnsupportedProtocol("HTTP protocol is disabled") class AsyncProxyTransportFixed(AsyncProxyTransport): """Fix httpx_socks.AsyncProxyTransport Map python_socks exceptions to httpcore.ProxyError Map socket.gaierror to httpcore.ConnectError Note: keepalive_expiry is ignored, AsyncProxyTransport should call: * self._keepalive_sweep() * self._response_closed(self, connection) Note: AsyncProxyTransport inherit from AsyncConnectionPool Note: the API is going to change on httpx 0.18.0 see https://github.com/encode/httpx/pull/1522 """ async def arequest(self, method, url, headers=None, stream=None, ext=None): retry = 2 while retry > 0: retry -= 1 try: return await super().arequest(method, url, headers, stream, ext) except (ProxyConnectionError, ProxyTimeoutError, ProxyError) as e: raise httpcore.ProxyError(e) except OSError as e: # socket.gaierror when DNS resolution fails raise httpcore.NetworkError(e) except httpcore.RemoteProtocolError as e: # in case of httpcore.RemoteProtocolError: Server disconnected await close_connections_for_url(self, url) logger.warning('httpcore.RemoteProtocolError: retry', exc_info=e) # retry except (httpcore.NetworkError, httpcore.ProtocolError) as e: # httpcore.WriteError on HTTP/2 connection leaves a new opened stream # then each new request creates a new stream and raise the same WriteError await close_connections_for_url(self, url) raise e class AsyncHTTPTransportFixed(httpx.AsyncHTTPTransport): """Fix httpx.AsyncHTTPTransport""" async def arequest(self, method, url, headers=None, stream=None, ext=None): retry = 2 while retry > 0: retry -= 1 try: return await super().arequest(method, url, headers, stream, ext) except OSError as e: # socket.gaierror when DNS resolution fails raise httpcore.ConnectError(e) except httpcore.CloseError as e: # httpcore.CloseError: [Errno 104] Connection reset by peer # raised by _keepalive_sweep() # from https://github.com/encode/httpcore/blob/4b662b5c42378a61e54d673b4c949420102379f5/httpcore/_backends/asyncio.py#L198 # pylint: disable=line-too-long await close_connections_for_url(self._pool, url) logger.warning('httpcore.CloseError: retry', exc_info=e) # retry except httpcore.RemoteProtocolError as e: # in case of httpcore.RemoteProtocolError: Server disconnected await close_connections_for_url(self._pool, url) logger.warning('httpcore.RemoteProtocolError: retry', exc_info=e) # retry except (httpcore.ProtocolError, httpcore.NetworkError) as e: await close_connections_for_url(self._pool, url) raise e def get_transport_for_socks_proxy(verify, http2, local_address, proxy_url, limit, retries): global TRANSPORT_KWARGS # support socks5h (requests compatibility): # https://requests.readthedocs.io/en/master/user/advanced/#socks # socks5:// hostname is resolved on client side # socks5h:// hostname is resolved on proxy side rdns = False socks5h = 'socks5h://' if proxy_url.startswith(socks5h): proxy_url = 'socks5://' + proxy_url[len(socks5h):] rdns = True proxy_type, proxy_host, proxy_port, proxy_username, proxy_password = parse_proxy_url(proxy_url) verify = get_sslcontexts(proxy_url, None, True, False, http2) if verify is True else verify return AsyncProxyTransportFixed(proxy_type=proxy_type, proxy_host=proxy_host, proxy_port=proxy_port, username=proxy_username, password=proxy_password, rdns=rdns, loop=get_loop(), verify=verify, http2=http2, local_address=local_address, max_connections=limit.max_connections, max_keepalive_connections=limit.max_keepalive_connections, keepalive_expiry=limit.keepalive_expiry, retries=retries, **TRANSPORT_KWARGS) def get_transport(verify, http2, local_address, proxy_url, limit, retries): global TRANSPORT_KWARGS verify = get_sslcontexts(None, None, True, False, http2) if verify is True else verify return AsyncHTTPTransportFixed( # pylint: disable=protected-access verify=verify, http2=http2, local_address=local_address, proxy=httpx._config.Proxy(proxy_url) if proxy_url else None, limits=limit, retries=retries, **TRANSPORT_KWARGS ) def iter_proxies(proxies): # https://www.python-httpx.org/compatibility/#proxy-keys if isinstance(proxies, str): yield 'all://', proxies elif isinstance(proxies, dict): for pattern, proxy_url in proxies.items(): yield pattern, proxy_url def new_client( # pylint: disable=too-many-arguments enable_http, verify, enable_http2, max_connections, max_keepalive_connections, keepalive_expiry, proxies, local_address, retries, max_redirects ): limit = httpx.Limits(max_connections=max_connections, max_keepalive_connections=max_keepalive_connections, keepalive_expiry=keepalive_expiry) # See https://www.python-httpx.org/advanced/#routing mounts = {} for pattern, proxy_url in iter_proxies(proxies): if not enable_http and (pattern == 'http' or pattern.startswith('http://')): continue if proxy_url.startswith('socks4://') \ or proxy_url.startswith('socks5://') \ or proxy_url.startswith('socks5h://'): mounts[pattern] = get_transport_for_socks_proxy(verify, enable_http2, local_address, proxy_url, limit, retries) else: mounts[pattern] = get_transport(verify, enable_http2, local_address, proxy_url, limit, retries) if not enable_http: mounts['http://'] = AsyncHTTPTransportNoHttp() transport = get_transport(verify, enable_http2, local_address, None, limit, retries) return httpx.AsyncClient(transport=transport, mounts=mounts, max_redirects=max_redirects) def get_loop(): global LOOP return LOOP def init(): # log for logger_name in ('hpack.hpack', 'hpack.table'): logging.getLogger(logger_name).setLevel(logging.WARNING) # loop def loop_thread(): global LOOP LOOP = asyncio.new_event_loop() LOOP.run_forever() thread = threading.Thread( target=loop_thread, name='asyncio_loop', daemon=True, ) thread.start() init()