feat(stdlib): Handle proxy tunnels in httlib integration

sentry_sdk/integrations/stdlib.py

@@ -69,10 +69,17 @@ def _install_httplib() -> None:
     def putrequest(
         self: "HTTPConnection", method: str, url: str, *args: "Any", **kwargs: "Any"
     ) -> "Any":
-        host = self.host
-        port = self.port
         default_port = self.default_port
 
+        # proxies go through set_tunnel
+        tunnel_host = getattr(self, "_tunnel_host", None)
+        if tunnel_host:
+            host = tunnel_host
+            port = getattr(self, "_tunnel_port", default_port)
+        else:
+            host = self.host
+            port = self.port
+
         client = sentry_sdk.get_client()
         if client.get_integration(StdlibIntegration) is None or is_sentry_url(
             client, host
@@ -104,6 +111,11 @@ def putrequest(
             span.set_data(SPANDATA.HTTP_QUERY, parsed_url.query)
             span.set_data(SPANDATA.HTTP_FRAGMENT, parsed_url.fragment)
 
+        # for proxies, these point to the proxy host/port
+        if tunnel_host:
+            span.set_data(SPANDATA.NETWORK_PEER_ADDRESS, self.host)
+            span.set_data(SPANDATA.NETWORK_PEER_PORT, self.port)
+
         rv = real_putrequest(self, method, url, *args, **kwargs)
 
         if should_propagate_trace(client, real_url):

tests/integrations/stdlib/test_httplib.py

@@ -1,7 +1,10 @@
 import os
 import datetime
+import socket
 from http.client import HTTPConnection, HTTPSConnection
+from http.server import BaseHTTPRequestHandler, HTTPServer
 from socket import SocketIO
+from threading import Thread
 from urllib.error import HTTPError
 from urllib.request import urlopen
 from unittest import mock
@@ -12,11 +15,35 @@
 from sentry_sdk.consts import MATCH_ALL, SPANDATA
 from sentry_sdk.integrations.stdlib import StdlibIntegration
 
-from tests.conftest import ApproxDict, create_mock_http_server
+from tests.conftest import ApproxDict, create_mock_http_server, get_free_port
 
 PORT = create_mock_http_server()
 
 
+class MockProxyRequestHandler(BaseHTTPRequestHandler):
+    def do_CONNECT(self):
+        self.send_response(200, "Connection Established")
+        self.end_headers()
+
+        self.rfile.readline()
+
+        response = b"HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n"
+        self.wfile.write(response)
+        self.wfile.flush()
+
+
+def create_mock_proxy_server():
+    proxy_port = get_free_port()
+    proxy_server = HTTPServer(("localhost", proxy_port), MockProxyRequestHandler)
+    proxy_thread = Thread(target=proxy_server.serve_forever)
+    proxy_thread.daemon = True
+    proxy_thread.start()
+    return proxy_port
+
+
+PROXY_PORT = create_mock_proxy_server()
+
+
 def test_crumb_capture(sentry_init, capture_events):
     sentry_init(integrations=[StdlibIntegration()])
     events = capture_events()
@@ -642,3 +669,25 @@ def test_http_timeout(monkeypatch, sentry_init, capture_envelopes):
     span = transaction["spans"][0]
     assert span["op"] == "http.client"
     assert span["description"] == f"GET http://localhost:{PORT}/bla"  # noqa: E231
+
+
+@pytest.mark.parametrize("tunnel_port", [8080, None])
+def test_proxy_http_tunnel(sentry_init, capture_events, tunnel_port):
+    sentry_init(traces_sample_rate=1.0)
+    events = capture_events()
+
+    with start_transaction(name="test_transaction"):
+        conn = HTTPConnection("localhost", PROXY_PORT)
+        conn.set_tunnel("api.example.com", tunnel_port)
+        conn.request("GET", "/foo")
+        conn.getresponse()
+
+    (event,) = events
+    (span,) = event["spans"]
+
+    port_modifier = f":{tunnel_port}" if tunnel_port else ""
+    assert span["description"] == f"GET http://api.example.com{port_modifier}/foo"
+    assert span["data"]["url"] == f"http://api.example.com{port_modifier}/foo"
+    assert span["data"][SPANDATA.HTTP_METHOD] == "GET"
+    assert span["data"][SPANDATA.NETWORK_PEER_ADDRESS] == "localhost"
+    assert span["data"][SPANDATA.NETWORK_PEER_PORT] == PROXY_PORT