searxng/searx/network/network.py
Markus Heiser e9157b3c1a [fix] issues when launching a local development server
A local development server can be launched by one of these command lines::

    $ flask --app searx.webapp run
    $ python -m searx.webapp

The different ways of starting the server should lead to the same result, which
is generally the case.  However, if the modules are reloaded after code
changes (reload option), it must be avoided that the application is initialized
twice at startup.  We have already discussed this in 2022 [1][2].

Further information on this topic can be found in [3][4][5].

To test a bash in the ./local environment was started and the follwing commands
had been executed::

    $ ./manage pyenv.cmd bash --norc --noprofile
    (py3) SEARXNG_DEBUG=1 flask --app searx.webapp run --reload
    (py3) SEARXNG_DEBUG=1 python -m searx.webapp

Since the generic parts of the docs also initialize the app to generate doc from
it, the build of the docs was also tested::

    $ make docs.clean docs.live

[1] https://github.com/searxng/searxng/pull/1656#issuecomment-1214198941
[2] https://github.com/searxng/searxng/pull/1616#issuecomment-1206137468
[3] https://flask.palletsprojects.com/en/stable/api/#flask.Flask.run
[4] https://github.com/pallets/flask/issues/5307#issuecomment-1774646119
[5] https://stackoverflow.com/a/25504196

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
2025-04-22 14:26:11 +02:00

432 lines
16 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
# pylint: disable=global-statement
# pylint: disable=missing-module-docstring, missing-class-docstring
from __future__ import annotations
import typing
import atexit
import asyncio
import ipaddress
from itertools import cycle
from typing import Dict
import httpx
from searx import logger, sxng_debug
from searx.extended_types import SXNG_Response
from .client import new_client, get_loop, AsyncHTTPTransportNoHttp
from .raise_for_httperror import raise_for_httperror
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]
yield from local_addresses
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 getattr(transport, "_pool") and getattr(
transport._pool, "_rdns", False # pylint: disable=protected-access
):
continue
return False
response = await client.get("https://check.torproject.org/api/ip", timeout=60)
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 sxng_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
@staticmethod
def extract_do_raise_for_httperror(kwargs):
do_raise_for_httperror = True
if 'raise_for_httperror' in kwargs:
do_raise_for_httperror = kwargs['raise_for_httperror']
del kwargs['raise_for_httperror']
return do_raise_for_httperror
def patch_response(self, response, do_raise_for_httperror) -> SXNG_Response:
if isinstance(response, httpx.Response):
response = typing.cast(SXNG_Response, response)
# requests compatibility (response is not streamed)
# see also https://www.python-httpx.org/compatibility/#checking-for-4xx5xx-responses
response.ok = not response.is_error
# raise an exception
if do_raise_for_httperror:
try:
raise_for_httperror(response)
except:
self._logger.warning(f"HTTP Request failed: {response.request.method} {response.request.url}")
raise
return response
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) -> SXNG_Response:
retries = self.retries
was_disconnected = False
do_raise_for_httperror = Network.extract_do_raise_for_httperror(kwargs)
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 self.patch_response(response, do_raise_for_httperror)
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': settings_outgoing['verify'],
'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/pull/2026
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()