general: use connection pooling and HTTP Keep-Alive (#39668)

passerelle/utils/__init__.py

@@ -23,6 +23,7 @@ from itertools import islice, chain
 import warnings
 
 from requests import Session as RequestSession, Response as RequestResponse
+from requests.adapters import HTTPAdapter
 from requests.structures import CaseInsensitiveDict
 from urllib3.exceptions import InsecureRequestWarning
 
@@ -210,10 +211,16 @@ def log_http_request(logger, request, response=None, exception=None, error_log=T
 # - use a proxy for HTTP and HTTPS if resource.http_proxy exists
 
 class Request(RequestSession):
+    ADAPTER_REGISTRY = {}  # connection pooling
+
     def __init__(self, *args, **kwargs):
         self.logger = kwargs.pop('logger')
         self.resource = kwargs.pop('resource', None)
         super(Request, self).__init__(*args, **kwargs)
+        if self.resource:
+            adapter = Request.ADAPTER_REGISTRY.setdefault(type(self.resource), HTTPAdapter())
+            self.mount('https://', adapter)
+            self.mount('http://', adapter)
 
     def request(self, method, url, **kwargs):
         cache_duration = kwargs.pop('cache_duration', None)