Add 304 benchmark for FileResponse (#10114)

(cherry picked from commit 9456955)

tests/test_benchmarks_web_fileresponse.py

@@ -3,9 +3,10 @@
 import asyncio
 import pathlib
 
+from multidict import CIMultiDict
 from pytest_codspeed import BenchmarkFixture
 
-from aiohttp import web
+from aiohttp import ClientResponse, web
 from aiohttp.pytest_plugin import AiohttpClient
 
 
@@ -24,15 +25,15 @@ async def handler(request: web.Request) -> web.FileResponse:
     app = web.Application()
     app.router.add_route("GET", "/", handler)
 
-    async def run_file_resonse_benchmark() -> None:
+    async def run_file_response_benchmark() -> None:
         client = await aiohttp_client(app)
         for _ in range(response_count):
             await client.get("/")
         await client.close()
 
     @benchmark
     def _run() -> None:
-        loop.run_until_complete(run_file_resonse_benchmark())
+        loop.run_until_complete(run_file_response_benchmark())
 
 
 def test_simple_web_file_sendfile_fallback_response(
@@ -53,12 +54,52 @@ async def handler(request: web.Request) -> web.FileResponse:
     app = web.Application()
     app.router.add_route("GET", "/", handler)
 
-    async def run_file_resonse_benchmark() -> None:
+    async def run_file_response_benchmark() -> None:
         client = await aiohttp_client(app)
         for _ in range(response_count):
             await client.get("/")
         await client.close()
 
     @benchmark
     def _run() -> None:
-        loop.run_until_complete(run_file_resonse_benchmark())
+        loop.run_until_complete(run_file_response_benchmark())
+
+
+def test_simple_web_file_response_not_modified(
+    loop: asyncio.AbstractEventLoop,
+    aiohttp_client: AiohttpClient,
+    benchmark: BenchmarkFixture,
+) -> None:
+    """Benchmark web.FileResponse that return a 304."""
+    response_count = 100
+    filepath = pathlib.Path(__file__).parent / "sample.txt"
+
+    async def handler(request: web.Request) -> web.FileResponse:
+        return web.FileResponse(path=filepath)
+
+    app = web.Application()
+    app.router.add_route("GET", "/", handler)
+
+    async def make_last_modified_header() -> CIMultiDict[str]:
+        client = await aiohttp_client(app)
+        resp = await client.get("/")
+        last_modified = resp.headers["Last-Modified"]
+        headers = CIMultiDict({"If-Modified-Since": last_modified})
+        return headers
+
+    async def run_file_response_benchmark(
+        headers: CIMultiDict[str],
+    ) -> ClientResponse:
+        client = await aiohttp_client(app)
+        for _ in range(response_count):
+            resp = await client.get("/", headers=headers)
+
+        await client.close()
+        return resp  # type: ignore[possibly-undefined]
+
+    headers = loop.run_until_complete(make_last_modified_header())
+
+    @benchmark
+    def _run() -> None:
+        resp = loop.run_until_complete(run_file_response_benchmark(headers))
+        assert resp.status == 304