fix(#256): PR feedback additional middelware testing

Author: captaincoordinates

pyproject.toml

@@ -63,6 +63,7 @@ dev = [
     "pytest-asyncio",
     "httpx",
     "pypgstac>=0.9.8,<=0.10",
+    "pytest-asyncio>=1.3.0,<2",
     "pytest-postgresql",
     "owslib",
     "pre-commit",

tests/test_middleware.py

@@ -0,0 +1,73 @@
+"""Test middlewares."""
+
+from typing import cast
+from unittest import mock
+from urllib.parse import quote
+
+import pytest
+from starlette.types import Receive, Scope, Send
+
+from titiler.pgstac.middleware import StripNulMiddleware
+
+
+@pytest.mark.asyncio
+async def test_strip_nul_middleware_with_nuls(app) -> None:
+    """Test nul byte stripping middleware with nul bytes."""
+    app_mock = mock.AsyncMock()
+    core_scope = {
+        "type": "http",
+    }
+    path_with_nul = "/path/with-{}/nul".format("\x00")
+    path_with_escaped_nul = "/path/with-{}/nul".format(quote("\x00"))
+    await StripNulMiddleware(app_mock)(
+        cast(
+            Scope,
+            {
+                **core_scope,
+                "path": path_with_nul,
+                "query_string": "param=query-with-{}-nul".format(quote("\x00")).encode(
+                    "utf-8"
+                ),
+                "raw_path": path_with_escaped_nul.encode("utf-8"),
+            },
+        ),
+        cast(Receive, None),
+        cast(Send, None),
+    )
+    path_without_null = "/path/with-/nul"
+    app_mock.assert_called_once_with(
+        {
+            **core_scope,
+            "path": path_without_null,
+            "query_string": "param=query-with--nul".encode("utf-8"),
+            "raw_path": path_without_null.encode("utf-8"),
+        },
+        None,
+        None,
+    )
+
+
+@pytest.mark.asyncio
+async def test_strip_nul_middleware_without_nuls(app) -> None:
+    """Test nul byte stripping middleware without any nul butes."""
+    app_mock = mock.AsyncMock()
+    path = "/path/without/nul"
+    core_scope = {
+        "type": "http",
+        "path": path,
+        "query_string": "param=query-without-nul".encode("utf-8"),
+        "raw_path": path.encode("utf-8"),
+    }
+    await StripNulMiddleware(app_mock)(
+        cast(
+            Scope,
+            core_scope,
+        ),
+        cast(Receive, None),
+        cast(Send, None),
+    )
+    app_mock.assert_called_once_with(
+        core_scope,
+        None,
+        None,
+    )

titiler/pgstac/middleware.py

@@ -33,10 +33,16 @@ async def __call__(self, scope: Scope, receive: Receive, send: Send):
             await self.app(scope, receive, send)
             return
 
-        scope["path"] = re.sub(_nul, "", scope["path"])
+        scope["path"] = re.sub(
+            _nul, "", scope["path"]
+        )  # nul in path is URL-unescaped at this point
         for property in ["query_string", "raw_path"]:
             scope[property] = re.sub(
-                quote(_nul), "", cast(bytes, scope[property]).decode(_encoding)
+                quote(_nul),
+                "",
+                cast(bytes, scope[property]).decode(
+                    _encoding
+                ),  # nul in these properties is URL-escaped
             ).encode(_encoding)
 
         await self.app(scope, receive, send)