Swap out requests-async for httpx (#1728)

* Begin swap of requests-async for httpx

* Finalize httpx adoption and resolve tests

Resolve linting and formatting

* Remove documentation references to requests-async in favor of httpx

tests/test_keep_alive_timeout.py

@@ -1,15 +1,9 @@
 import asyncio
-import functools
-import socket
 
 from asyncio import sleep as aio_sleep
-from http.client import _encode
 from json import JSONDecodeError
 
-import httpcore
-import requests_async as requests
-
-from httpcore import PoolTimeout
+import httpx
 
 from sanic import Sanic, server
 from sanic.response import text
@@ -21,24 +15,28 @@ CONFIG_FOR_TESTS = {"KEEP_ALIVE_TIMEOUT": 2, "KEEP_ALIVE": True}
 old_conn = None
 
 
-class ReusableSanicConnectionPool(httpcore.ConnectionPool):
-    async def acquire_connection(self, origin):
+class ReusableSanicConnectionPool(
+    httpx.dispatch.connection_pool.ConnectionPool
+):
+    async def acquire_connection(self, origin, timeout):
         global old_conn
-        connection = self.active_connections.pop_by_origin(
-            origin, http2_only=True
-        )
-        if connection is None:
-            connection = self.keepalive_connections.pop_by_origin(origin)
+        connection = self.pop_connection(origin)
 
         if connection is None:
-            await self.max_connections.acquire()
-            connection = httpcore.HTTPConnection(
+            pool_timeout = None if timeout is None else timeout.pool_timeout
+
+            await self.max_connections.acquire(timeout=pool_timeout)
+            connection = httpx.dispatch.connection.HTTPConnection(
                 origin,
-                ssl=self.ssl,
-                timeout=self.timeout,
+                verify=self.verify,
+                cert=self.cert,
+                http2=self.http2,
                 backend=self.backend,
                 release_func=self.release_connection,
+                trust_env=self.trust_env,
+                uds=self.uds,
             )
+
         self.active_connections.add(connection)
 
         if old_conn is not None:
@@ -51,17 +49,10 @@ class ReusableSanicConnectionPool(httpcore.ConnectionPool):
         return connection
 
 
-class ReusableSanicAdapter(requests.adapters.HTTPAdapter):
-    def __init__(self):
-        self.pool = ReusableSanicConnectionPool()
-
-
-class ResusableSanicSession(requests.Session):
+class ResusableSanicSession(httpx.Client):
     def __init__(self, *args, **kwargs) -> None:
-        super().__init__(*args, **kwargs)
-        adapter = ReusableSanicAdapter()
-        self.mount("http://", adapter)
-        self.mount("https://", adapter)
+        dispatch = ReusableSanicConnectionPool()
+        super().__init__(dispatch=dispatch, *args, **kwargs)
 
 
 class ReuseableSanicTestClient(SanicTestClient):
@@ -74,6 +65,9 @@ class ReuseableSanicTestClient(SanicTestClient):
         self._tcp_connector = None
         self._session = None
 
+    def get_new_session(self):
+        return ResusableSanicSession()
+
     # Copied from SanicTestClient, but with some changes to reuse the
     # same loop for the same app.
     def _sanic_endpoint_test(
@@ -167,7 +161,6 @@ class ReuseableSanicTestClient(SanicTestClient):
                 self._server.close()
                 self._loop.run_until_complete(self._server.wait_closed())
                 self._server = None
-                self.app.stop()
 
             if self._session:
                 self._loop.run_until_complete(self._session.close())
@@ -186,7 +179,7 @@ class ReuseableSanicTestClient(SanicTestClient):
             "request_keepalive", CONFIG_FOR_TESTS["KEEP_ALIVE_TIMEOUT"]
         )
         if not self._session:
-            self._session = ResusableSanicSession()
+            self._session = self.get_new_session()
         try:
             response = await getattr(self._session, method.lower())(
                 url, verify=False, timeout=request_keepalive, *args, **kwargs