## What does this PR do?
This PR prepares for removing `httpx`, and reverts back to `requests`.
## Why is this change important?
`httpx` hasn't proven itself to be faster or better than `requests`. On the other
hand it has caused issues on Windows.
=============================================
Please update your environment to use requests instead of httpx.
=============================================
settings.yml:
* outgoing.networks:
* can contains network definition
* propertiers: enable_http, verify, http2, max_connections, max_keepalive_connections,
keepalive_expiry, local_addresses, support_ipv4, support_ipv6, proxies, max_redirects, retries
* retries: 0 by default, number of times searx retries to send the HTTP request (using different IP & proxy each time)
* local_addresses can be "192.168.0.1/24" (it supports IPv6)
* support_ipv4 & support_ipv6: both True by default
see https://github.com/searx/searx/pull/1034
* each engine can define a "network" section:
* either a full network description
* either reference an existing network
* all HTTP requests of engine use the same HTTP configuration (it was not the case before, see proxy configuration in master)
The duckduckgo engine requires an additional request after the results have been sent.
This commit makes sure that the second request uses the same HTTPAdapter
= the same IP address, and the same proxy.
check HTTP response:
* detect some comme CAPTCHA challenge (no solving). In this case the engine is suspended for long a time.
* otherwise raise HTTPError as before
the check is done in poolrequests.py (was before in search.py).
update qwant, wikipedia, wikidata to use raise_for_httperror instead of raise_for_status
requests 2.24.0 uses the ssl module except if it doesn't support SNI, in this case searx fallbacks to pyopenssl.
searx logs a critical message and exit if the ssl modules doesn't support SNI and pyOpenSSL is not installed.
searx logs a critical message and exit if the ssl version is older than 1.0.2.
in requirements.txt, pyopenssl is still required to install searx as a fallback.