raw_socket_proxy: add simple echo tests

tests/resources/jupyter_server_config.py

@@ -127,6 +127,15 @@ def my_env():
         "rewrite_response": [cats_only, dog_to_cat],
     },
     "python-proxyto54321-no-command": {"port": 54321},
+    "python-rawsocket-tcp": {
+        "command": [sys.executable, "./tests/resources/rawsocket.py", "{port}"],
+        "raw_socket_proxy": True
+    },
+    "python-rawsocket-unix": {
+        "command": [sys.executable, "./tests/resources/rawsocket.py", "{unix_socket}"],
+        "unix_socket": True,
+        "raw_socket_proxy": True
+    },
 }
 
 c.ServerProxy.non_service_rewrite_response = hello_to_foo

tests/resources/rawsocket.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+import os
+import socket
+import sys
+
+if len(sys.argv) != 2:
+    print(f"Usage: {sys.argv[0]} TCPPORT|SOCKPATH")
+    sys.exit(1)
+where = sys.argv[1]
+try:
+    port = int(where)
+    family = socket.AF_INET
+    addr = ('localhost', port)
+except ValueError:
+    family = socket.AF_UNIX
+    addr = where
+
+with socket.create_server(addr, family=family, reuse_port=True) as serv:
+    while True:
+        # only handle a single connection at a time
+        sock, caddr = serv.accept()
+        while True:
+            s = sock.recv(1024)
+            if not s:
+                break
+            sock.send(s.swapcase())
+        sock.close()

tests/test_proxies.py

@@ -469,3 +469,25 @@ def test_callable_environment_formatting(
     PORT, TOKEN = a_server_port_and_token
     r = request_get(PORT, "/python-http-callable-env/test", TOKEN)
     assert r.code == 200
+
+
+@pytest.mark.parametrize("rawsocket_type", [
+    "tcp",
+    pytest.param(
+        "unix",
+        marks=pytest.mark.skipif(
+            sys.platform == "win32", reason="Unix socket not supported on Windows"
+        ),
+    ),
+])
+async def test_server_proxy_rawsocket(
+    rawsocket_type: str,
+    a_server_port_and_token: Tuple[int, str]
+) -> None:
+    PORT, TOKEN = a_server_port_and_token
+    url = f"ws://{LOCALHOST}:{PORT}/python-rawsocket-{rawsocket_type}/?token={TOKEN}"
+    conn = await websocket_connect(url)
+    for msg in [b"Hello,", b"world!"]:
+        await conn.write_message(msg)
+        res = await conn.read_message()
+        assert res == msg.swapcase()