fix(cookbook): harden remote serve host handling (#4345)

tests/test_cookbook_remote_windows_diffusers.py

@@ -0,0 +1,57 @@
+import asyncio
+
+import pytest
+from fastapi import HTTPException
+from starlette.requests import Request
+
+import routes.cookbook_routes as cookbook_routes
+from routes.cookbook_helpers import ServeRequest
+
+
+def _route_endpoint(path: str, method: str):
+    router = cookbook_routes.setup_cookbook_routes()
+    for route in router.routes:
+        if route.path == path and method in route.methods:
+            return route.endpoint
+    raise AssertionError(f"{method} {path} route not found")
+
+
+def _admin_request() -> Request:
+    request = Request(
+        {
+            "type": "http",
+            "method": "POST",
+            "path": "/api/model/serve",
+            "headers": [],
+            "state": {},
+        }
+    )
+    request.state.current_user = "admin"
+    return request
+
+
+@pytest.mark.asyncio
+async def test_remote_windows_diffusers_is_rejected_before_runner_launch(monkeypatch):
+    monkeypatch.setattr(cookbook_routes, "require_admin", lambda request: None)
+    calls = []
+
+    async def fail_if_shell_runs(*args, **kwargs):
+        calls.append((args, kwargs))
+        raise AssertionError("remote Windows Diffusers should fail before shell launch")
+
+    monkeypatch.setattr(asyncio, "create_subprocess_shell", fail_if_shell_runs)
+
+    endpoint = _route_endpoint("/api/model/serve", "POST")
+    req = ServeRequest(
+        repo_id="diffusers/example",
+        cmd="python scripts/diffusion_server.py --model diffusers/example --port 8100",
+        remote_host="winbox",
+        platform="windows",
+    )
+
+    with pytest.raises(HTTPException) as exc:
+        await endpoint(_admin_request(), req)
+
+    assert exc.value.status_code == 400
+    assert "Remote Windows Diffusers" in str(exc.value.detail)
+    assert calls == []