sgl-router: experimental Rust HTTP router for SGLang worker pools (#25851)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

experimental/sgl-router/tests/e2e/test_chat_smoke.py

@@ -0,0 +1,64 @@
+"""
+Smoke tests for /v1/models and /v1/chat/completions (streaming + non-streaming).
+"""
+
+from __future__ import annotations
+
+import httpx
+import pytest
+
+MODEL = "Qwen/Qwen3-0.6B"
+
+
+def test_models(router: str) -> None:
+    """GET /v1/models must list the configured model."""
+    resp = httpx.get(f"{router}/v1/models", timeout=30)
+    assert resp.status_code == 200, resp.text
+    data = resp.json()
+    ids = [m["id"] for m in data.get("data", [])]
+    assert any(
+        MODEL in mid for mid in ids
+    ), f"Model {MODEL!r} not found in /v1/models response: {ids}"
+
+
+def test_chat_non_streaming(router: str) -> None:
+    """POST /v1/chat/completions (stream=False) returns an assistant message."""
+    payload = {
+        "model": MODEL,
+        "messages": [{"role": "user", "content": "Say hi."}],
+        "max_tokens": 10,
+        "stream": False,
+    }
+    resp = httpx.post(f"{router}/v1/chat/completions", json=payload, timeout=60)
+    assert resp.status_code == 200, resp.text
+    body = resp.json()
+    choice = body["choices"][0]
+    assert choice["message"]["role"] == "assistant"
+    assert choice["message"]["content"], "Expected non-empty assistant content"
+
+
+def test_chat_streaming(router: str) -> None:
+    """POST /v1/chat/completions (stream=True) returns >=2 SSE chunks incl. [DONE]."""
+    payload = {
+        "model": MODEL,
+        "messages": [{"role": "user", "content": "Say hi."}],
+        "max_tokens": 10,
+        "stream": True,
+    }
+    chunks: list[str] = []
+    with httpx.stream(
+        "POST",
+        f"{router}/v1/chat/completions",
+        json=payload,
+        timeout=60,
+    ) as resp:
+        assert resp.status_code == 200, resp.read().decode()
+        for line in resp.iter_lines():
+            line = line.strip()
+            if line.startswith("data:"):
+                chunks.append(line)
+
+    assert len(chunks) >= 2, f"Expected >=2 SSE chunks, got {len(chunks)}: {chunks}"
+    assert any(
+        "[DONE]" in c for c in chunks
+    ), f"No [DONE] chunk found in SSE stream: {chunks}"