fix(bench): wire request_func in bench_long_context ContextWorkloadGenerator (#23898)

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

benchmark/hicache/bench_long_context.py

@@ -13,13 +13,13 @@ from bench_multiturn import (
 from tqdm.asyncio import tqdm
 
 from sglang.benchmark.utils import get_tokenizer
+from sglang.test.kits.cache_hit_kit import async_request_sglang_generate
 
 
 class ContextWorkloadGenerator(WorkloadGenerator):
     def __init__(self, args):
-        # Construct the base URL for requests
-        self.baseurl = f"http://{args.host}:{args.port}/"
-        self.url = self.baseurl + "generate"
+        self.url = f"http://{args.host}:{args.port}/generate"
+        self.request_func = async_request_sglang_generate
 
         self.tokenizer = get_tokenizer(args.model_path)
         self.distribution = args.distribution

test/registered/unit/test_bench_long_context.py

@@ -0,0 +1,128 @@
+"""Unit test for benchmark/hicache/bench_long_context.py.
+
+Guards against the regression where ContextWorkloadGenerator.__init__ replaces
+WorkloadGenerator.__init__ entirely but forgets to set attributes the inherited
+request_sender/handle_request methods need (e.g. self.request_func).
+"""
+
+import json
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+from types import SimpleNamespace
+from unittest.mock import MagicMock, patch
+
+from sglang.test.ci.ci_register import register_cpu_ci
+from sglang.test.test_utils import CustomTestCase
+
+register_cpu_ci(est_time=5, suite="stage-a-test-cpu")
+
+REPO_ROOT = Path(__file__).resolve().parents[3]
+HICACHE_DIR = REPO_ROOT / "benchmark" / "hicache"
+if str(HICACHE_DIR) not in sys.path:
+    sys.path.insert(0, str(HICACHE_DIR))
+
+import bench_long_context  # noqa: E402
+
+from sglang.test.kits.cache_hit_kit import async_request_sglang_generate  # noqa: E402
+
+
+def _build_args(dataset_path: str) -> SimpleNamespace:
+    return SimpleNamespace(
+        host="localhost",
+        port=30000,
+        model_path="meta-llama/Llama-3.2-1B-Instruct",
+        distribution="poisson",
+        request_rate=1.0,
+        dataset_path=dataset_path,
+        num_clients=2,
+        max_parallel=2,
+        log_file="performance_metrics.jsonl",
+        tag="",
+    )
+
+
+def _fake_dataset() -> dict:
+    return {
+        "contexts": ["ctx-zero ", "ctx-one "],
+        "queries": [
+            {"context": 0, "question": "q0", "reference_answer": "a0"},
+            {"context": 1, "question": "q1", "reference_answer": "a1"},
+        ],
+    }
+
+
+class TestContextWorkloadGeneratorInit(CustomTestCase):
+    """Verify ContextWorkloadGenerator wires up everything its inherited
+    request_sender/handle_request/run methods rely on."""
+
+    def setUp(self):
+        self._tmp = tempfile.NamedTemporaryFile(mode="w", suffix=".json", delete=False)
+        json.dump(_fake_dataset(), self._tmp)
+        self._tmp.close()
+        self.dataset_path = self._tmp.name
+
+        mock_tokenizer = MagicMock()
+        mock_tokenizer.encode.return_value = [1, 2, 3, 4]
+        mock_tokenizer.return_value = {"input_ids": [5, 6]}
+
+        self._tok_patch = patch.object(
+            bench_long_context, "get_tokenizer", return_value=mock_tokenizer
+        )
+        self._tok_patch.start()
+
+    def tearDown(self):
+        self._tok_patch.stop()
+        Path(self.dataset_path).unlink(missing_ok=True)
+
+    def test_request_func_is_set(self):
+        """The bug we're guarding against: request_func not being set caused
+        AttributeError as soon as the request_sender thread fired."""
+        gen = bench_long_context.ContextWorkloadGenerator(
+            _build_args(self.dataset_path)
+        )
+        self.assertTrue(callable(getattr(gen, "request_func", None)))
+        self.assertIs(gen.request_func, async_request_sglang_generate)
+
+    def test_inherits_workload_generator_contract(self):
+        """All attributes WorkloadGenerator's run-time methods touch must exist."""
+        gen = bench_long_context.ContextWorkloadGenerator(
+            _build_args(self.dataset_path)
+        )
+
+        # handle_request (bench_multiturn.py) reads these
+        for attr in ("request_func", "url", "pbar", "response_queue", "finished_time"):
+            self.assertTrue(hasattr(gen, attr), f"missing attribute: {attr}")
+
+        # request_sender reads these
+        for attr in (
+            "sent_requests",
+            "completed_requests",
+            "max_parallel",
+            "ready_queue",
+            "distribution",
+            "request_rate",
+        ):
+            self.assertTrue(hasattr(gen, attr), f"missing attribute: {attr}")
+
+        # run() reads these
+        for attr in ("performance_metrics", "enable_round_barrier"):
+            self.assertTrue(hasattr(gen, attr), f"missing attribute: {attr}")
+
+    def test_url_targets_sglang_generate_endpoint(self):
+        gen = bench_long_context.ContextWorkloadGenerator(
+            _build_args(self.dataset_path)
+        )
+        self.assertEqual(gen.url, "http://localhost:30000/generate")
+
+    def test_ready_queue_size_matches_dataset(self):
+        gen = bench_long_context.ContextWorkloadGenerator(
+            _build_args(self.dataset_path)
+        )
+        # 2 queries in fake dataset, num_clients=2 → 2 init requests
+        self.assertEqual(len(gen.ready_queue.requests), 2)
+
+
+if __name__ == "__main__":
+    unittest.main()