# SPDX-License-Identifier: AGPL-3.0-or-later # lint: pylint # pylint: disable=global-statement # pylint: disable=missing-module-docstring, missing-class-docstring import atexit import asyncio import ipaddress from itertools import cycle from typing import Dict import httpx from searx import logger, searx_debug from .client import new_client, get_loop, AsyncHTTPTransportNoHttp logger = logger.getChild('network') DEFAULT_NAME = '__DEFAULT__' NETWORKS: Dict[str, 'Network'] = {} # requests compatibility when reading proxy settings from settings.yml PROXY_PATTERN_MAPPING = { 'http': 'http://', 'https': 'https://', 'socks4': 'socks4://', 'socks5': 'socks5://', 'socks5h': 'socks5h://', 'http:': 'http://', 'https:': 'https://', 'socks4:': 'socks4://', 'socks5:': 'socks5://', 'socks5h:': 'socks5h://', } ADDRESS_MAPPING = {'ipv4': '0.0.0.0', 'ipv6': '::'} class Network: __slots__ = ( 'enable_http', 'verify', 'enable_http2', 'max_connections', 'max_keepalive_connections', 'keepalive_expiry', 'local_addresses', 'proxies', 'using_tor_proxy', 'max_redirects', 'retries', 'retry_on_http_error', '_local_addresses_cycle', '_proxies_cycle', '_clients', '_logger', ) _TOR_CHECK_RESULT = {} def __init__( # pylint: disable=too-many-arguments self, enable_http=True, verify=True, enable_http2=False, max_connections=None, max_keepalive_connections=None, keepalive_expiry=None, proxies=None, using_tor_proxy=False, local_addresses=None, retries=0, retry_on_http_error=None, max_redirects=30, logger_name=None, ): self.enable_http = enable_http self.verify = verify self.enable_http2 = enable_http2 self.max_connections = max_connections self.max_keepalive_connections = max_keepalive_connections self.keepalive_expiry = keepalive_expiry self.proxies = proxies self.using_tor_proxy = using_tor_proxy self.local_addresses = local_addresses self.retries = retries self.retry_on_http_error = retry_on_http_error self.max_redirects = max_redirects self._local_addresses_cycle = self.get_ipaddress_cycle() self._proxies_cycle = self.get_proxy_cycles() self._clients = {} self._logger = logger.getChild(logger_name) if logger_name else logger self.check_parameters() def check_parameters(self): for address in self.iter_ipaddresses(): if '/' in address: ipaddress.ip_network(address, False) else: ipaddress.ip_address(address) if self.proxies is not None and not isinstance(self.proxies, (str, dict)): raise ValueError('proxies type has to be str, dict or None') def iter_ipaddresses(self): local_addresses = self.local_addresses if not local_addresses: return if isinstance(local_addresses, str): local_addresses = [local_addresses] for address in local_addresses: yield address def get_ipaddress_cycle(self): while True: count = 0 for address in self.iter_ipaddresses(): if '/' in address: for a in ipaddress.ip_network(address, False).hosts(): yield str(a) count += 1 else: a = ipaddress.ip_address(address) yield str(a) count += 1 if count == 0: yield None def iter_proxies(self): if not self.proxies: return # https://www.python-httpx.org/compatibility/#proxy-keys if isinstance(self.proxies, str): yield 'all://', [self.proxies] else: for pattern, proxy_url in self.proxies.items(): pattern = PROXY_PATTERN_MAPPING.get(pattern, pattern) if isinstance(proxy_url, str): proxy_url = [proxy_url] yield pattern, proxy_url def get_proxy_cycles(self): proxy_settings = {} for pattern, proxy_urls in self.iter_proxies(): proxy_settings[pattern] = cycle(proxy_urls) while True: # pylint: disable=stop-iteration-return yield tuple((pattern, next(proxy_url_cycle)) for pattern, proxy_url_cycle in proxy_settings.items()) async def log_response(self, response: httpx.Response): request = response.request status = f"{response.status_code} {response.reason_phrase}" response_line = f"{response.http_version} {status}" content_type = response.headers.get("Content-Type") content_type = f' ({content_type})' if content_type else '' self._logger.debug(f'HTTP Request: {request.method} {request.url} "{response_line}"{content_type}') @staticmethod async def check_tor_proxy(client: httpx.AsyncClient, proxies) -> bool: if proxies in Network._TOR_CHECK_RESULT: return Network._TOR_CHECK_RESULT[proxies] result = True # ignore client._transport because it is not used with all:// for transport in client._mounts.values(): # pylint: disable=protected-access if isinstance(transport, AsyncHTTPTransportNoHttp): continue if not getattr(transport, '_rdns', False): result = False break else: response = await client.get('https://check.torproject.org/api/ip') if not response.json()['IsTor']: result = False Network._TOR_CHECK_RESULT[proxies] = result return result async def get_client(self, verify=None, max_redirects=None): verify = self.verify if verify is None else verify max_redirects = self.max_redirects if max_redirects is None else max_redirects local_address = next(self._local_addresses_cycle) proxies = next(self._proxies_cycle) # is a tuple so it can be part of the key key = (verify, max_redirects, local_address, proxies) hook_log_response = self.log_response if searx_debug else None if key not in self._clients or self._clients[key].is_closed: client = new_client( self.enable_http, verify, self.enable_http2, self.max_connections, self.max_keepalive_connections, self.keepalive_expiry, dict(proxies), local_address, 0, max_redirects, hook_log_response, ) if self.using_tor_proxy and not await self.check_tor_proxy(client, proxies): await client.aclose() raise httpx.ProxyError('Network configuration problem: not using Tor') self._clients[key] = client return self._clients[key] async def aclose(self): async def close_client(client): try: await client.aclose() except httpx.HTTPError: pass await asyncio.gather(*[close_client(client) for client in self._clients.values()], return_exceptions=False) @staticmethod def extract_kwargs_clients(kwargs): kwargs_clients = {} if 'verify' in kwargs: kwargs_clients['verify'] = kwargs.pop('verify') if 'max_redirects' in kwargs: kwargs_clients['max_redirects'] = kwargs.pop('max_redirects') if 'allow_redirects' in kwargs: # see https://github.com/encode/httpx/pull/1808 kwargs['follow_redirects'] = kwargs.pop('allow_redirects') return kwargs_clients def is_valid_response(self, response): # pylint: disable=too-many-boolean-expressions if ( (self.retry_on_http_error is True and 400 <= response.status_code <= 599) or (isinstance(self.retry_on_http_error, list) and response.status_code in self.retry_on_http_error) or (isinstance(self.retry_on_http_error, int) and response.status_code == self.retry_on_http_error) ): return False return True async def call_client(self, stream, method, url, **kwargs): retries = self.retries was_disconnected = False kwargs_clients = Network.extract_kwargs_clients(kwargs) while retries >= 0: # pragma: no cover client = await self.get_client(**kwargs_clients) try: if stream: response = client.stream(method, url, **kwargs) else: response = await client.request(method, url, **kwargs) if self.is_valid_response(response) or retries <= 0: return response except httpx.RemoteProtocolError as e: if not was_disconnected: # the server has closed the connection: # try again without decreasing the retries variable & with a new HTTP client was_disconnected = True await client.aclose() self._logger.warning('httpx.RemoteProtocolError: the server has disconnected, retrying') continue if retries <= 0: raise e except (httpx.RequestError, httpx.HTTPStatusError) as e: if retries <= 0: raise e retries -= 1 async def request(self, method, url, **kwargs): return await self.call_client(False, method, url, **kwargs) async def stream(self, method, url, **kwargs): return await self.call_client(True, method, url, **kwargs) @classmethod async def aclose_all(cls): await asyncio.gather(*[network.aclose() for network in NETWORKS.values()], return_exceptions=False) def get_network(name=None): return NETWORKS.get(name or DEFAULT_NAME) def check_network_configuration(): async def check(): exception_count = 0 for network in NETWORKS.values(): if network.using_tor_proxy: try: await network.get_client() except Exception: # pylint: disable=broad-except network._logger.exception('Error') # pylint: disable=protected-access exception_count += 1 return exception_count future = asyncio.run_coroutine_threadsafe(check(), get_loop()) exception_count = future.result() if exception_count > 0: raise RuntimeError("Invalid network configuration") def initialize(settings_engines=None, settings_outgoing=None): # pylint: disable=import-outside-toplevel) from searx.engines import engines from searx import settings # pylint: enable=import-outside-toplevel) settings_engines = settings_engines or settings['engines'] settings_outgoing = settings_outgoing or settings['outgoing'] # default parameters for AsyncHTTPTransport # see https://github.com/encode/httpx/blob/e05a5372eb6172287458b37447c30f650047e1b8/httpx/_transports/default.py#L108-L121 # pylint: disable=line-too-long default_params = { 'enable_http': False, 'verify': True, 'enable_http2': settings_outgoing['enable_http2'], 'max_connections': settings_outgoing['pool_connections'], 'max_keepalive_connections': settings_outgoing['pool_maxsize'], 'keepalive_expiry': settings_outgoing['keepalive_expiry'], 'local_addresses': settings_outgoing['source_ips'], 'using_tor_proxy': settings_outgoing['using_tor_proxy'], 'proxies': settings_outgoing['proxies'], 'max_redirects': settings_outgoing['max_redirects'], 'retries': settings_outgoing['retries'], 'retry_on_http_error': None, } def new_network(params, logger_name=None): nonlocal default_params result = {} result.update(default_params) result.update(params) if logger_name: result['logger_name'] = logger_name return Network(**result) def iter_networks(): nonlocal settings_engines for engine_spec in settings_engines: engine_name = engine_spec['name'] engine = engines.get(engine_name) if engine is None: continue network = getattr(engine, 'network', None) yield engine_name, engine, network if NETWORKS: done() NETWORKS.clear() NETWORKS[DEFAULT_NAME] = new_network({}, logger_name='default') NETWORKS['ipv4'] = new_network({'local_addresses': '0.0.0.0'}, logger_name='ipv4') NETWORKS['ipv6'] = new_network({'local_addresses': '::'}, logger_name='ipv6') # define networks from outgoing.networks for network_name, network in settings_outgoing['networks'].items(): NETWORKS[network_name] = new_network(network, logger_name=network_name) # define networks from engines.[i].network (except references) for engine_name, engine, network in iter_networks(): if network is None: network = {} for attribute_name, attribute_value in default_params.items(): if hasattr(engine, attribute_name): network[attribute_name] = getattr(engine, attribute_name) else: network[attribute_name] = attribute_value NETWORKS[engine_name] = new_network(network, logger_name=engine_name) elif isinstance(network, dict): NETWORKS[engine_name] = new_network(network, logger_name=engine_name) # define networks from engines.[i].network (references) for engine_name, engine, network in iter_networks(): if isinstance(network, str): NETWORKS[engine_name] = NETWORKS[network] # the /image_proxy endpoint has a dedicated network. # same parameters than the default network, but HTTP/2 is disabled. # It decreases the CPU load average, and the total time is more or less the same if 'image_proxy' not in NETWORKS: image_proxy_params = default_params.copy() image_proxy_params['enable_http2'] = False NETWORKS['image_proxy'] = new_network(image_proxy_params, logger_name='image_proxy') @atexit.register def done(): """Close all HTTP client Avoid a warning at exit see https://github.com/encode/httpx/blob/1a6e254f72d9fd5694a1c10a28927e193ab4f76b/httpx/_client.py#L1785 Note: since Network.aclose has to be async, it is not possible to call this method on Network.__del__ So Network.aclose is called here using atexit.register """ try: loop = get_loop() if loop: future = asyncio.run_coroutine_threadsafe(Network.aclose_all(), loop) # wait 3 seconds to close the HTTP clients future.result(3) finally: NETWORKS.clear() NETWORKS[DEFAULT_NAME] = Network()