re-implement simple CORS middleware for blackd (#2500)

* re-implement simple CORS middleware for blackd
* remove aiohttp-cors from setup.py
* Remove aiohttp-cors from Pipfile.lock

Co-authored-by: Richard Si <63936253+ichard26@users.noreply.github.com>

diff --git a/CHANGES.md b/CHANGES.md
index 6ff488ba74e98ea0e18a4d97c5e55fc1045264de..2a9b649d25cfe0776a34e655dd85b8b36bf20781 100644 (file)
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,11 @@
 # Change Log
 
+## Unreleased
+
+### _Blackd_
+
+- Remove dependency on aiohttp-cors (#2500)
+
 ## 21.9b0
 
 ### Packaging

diff --git a/Pipfile b/Pipfile
index 824beda16ccedac93c8736cfb46a1e2705506f41..66ded8b857010019cc7e26432c6591a3993a4482 100644 (file)
--- a/Pipfile
+++ b/Pipfile
@@ -41,7 +41,6 @@ black = {editable = true, extras = ["d", "jupyter"], path = "."}
 
 [packages]
 aiohttp = ">=3.6.0"
-aiohttp-cors = ">=0.4.0"
 platformdirs= ">=2"
 click = ">=8.0.0"
 mypy_extensions = ">=0.4.3"

diff --git a/Pipfile.lock b/Pipfile.lock
index 30a4defcca35d48f82c91bbe80fd978343f6b65b..0cbe90119810eb229c3a3f4c446a9d4b48d41d63 100644 (file)
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "ebf216584cfb2c962a1792d0682f3c08b44c7ae27305a03a54eacd6f42df27db"
+            "sha256": "8b28e41c5a63f0c30361d2a0ed29dc1e3f0468223ef150ae68586839e2ccf1c9"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -57,14 +57,6 @@
             "index": "pypi",
             "version": "==3.7.4.post0"
         },
-        "aiohttp-cors": {
-            "hashes": [
-                "sha256:0451ba59fdf6909d0e2cd21e4c0a43752bc0703d33fc78ae94d9d9321710193e",
-                "sha256:4d39c6d7100fd9764ed1caf8cebf0eb01bf5e3f24e2e073fda6234bc48b19f5d"
-            ],
-            "index": "pypi",
-            "version": "==0.7.0"
-        },
         "async-timeout": {
             "hashes": [
                 "sha256:0c3c816a028d47f659d6ff5c745cb2acf1f966da1fe5c19c77a70282b25f4c5f",
@@ -188,6 +180,14 @@
             "index": "pypi",
             "version": "==0.4.3"
         },
+        "packaging": {
+            "hashes": [
+                "sha256:7dc96269f53a4ccec5c0670940a4281106dd0bb343f47b7471f779df49c2fbe7",
+                "sha256:c86254f9220d55e31cc94d69bade760f0847da8000def4dfe1c6b872fd14ff14"
+            ],
+            "markers": "python_version >= '3.6'",
+            "version": "==21.0"
+        },
         "pathspec": {
             "hashes": [
                 "sha256:7d15c4ddb0b5c802d161efc417ec1a2558ea2653c2e8ad9c19098201dc1c993a",
@@ -204,6 +204,14 @@
             "index": "pypi",
             "version": "==2.2.0"
         },
+        "pyparsing": {
+            "hashes": [
+                "sha256:c203ec8783bf771a155b207279b9bccb8dea02d8f0c9e5f8ead507bc3246ecc1",
+                "sha256:ef9d7589ef3c200abe66653d3f1ab1033c3c419ae9b9bdb1240a85b024efc88b"
+            ],
+            "markers": "python_version >= '2.6' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==2.4.7"
+        },
         "regex": {
             "hashes": [
                 "sha256:03840a07a402576b8e3a6261f17eb88abd653ad4e18ec46ef10c9a63f8c99ebd",
@@ -252,6 +260,9 @@
             "version": "==2021.8.21"
         },
         "setuptools-scm": {
+            "extras": [
+                "toml"
+            ],
             "hashes": [
                 "sha256:c3bd5f701c8def44a5c0bfe8d407bef3f80342217ef3492b951f3777bd2d915c",
                 "sha256:d1925a69cb07e9b29416a275b9fadb009a23c148ace905b2fb220649a6c18e92"
@@ -410,14 +421,6 @@
             "index": "pypi",
             "version": "==3.7.4.post0"
         },
-        "aiohttp-cors": {
-            "hashes": [
-                "sha256:0451ba59fdf6909d0e2cd21e4c0a43752bc0703d33fc78ae94d9d9321710193e",
-                "sha256:4d39c6d7100fd9764ed1caf8cebf0eb01bf5e3f24e2e073fda6234bc48b19f5d"
-            ],
-            "index": "pypi",
-            "version": "==0.7.0"
-        },
         "alabaster": {
             "hashes": [
                 "sha256:446438bdcca0e05bd45ea2de1668c1d9b032e1a9154c2c259092d77031ddd359",
@@ -769,7 +772,7 @@
                 "sha256:2480d8e07d1890056cb53c96e3de44fead9c62f2ba949b0f2e4c4345f4afa977",
                 "sha256:a65882a4d0fe5fbf702273456ba2ce74fe44892c25e42e057aca526b702a6d4b"
             ],
-            "markers": "python_version < '3.7' and python_version < '3.7'",
+            "markers": "python_version < '3.7'",
             "version": "==5.2.2"
         },
         "iniconfig": {
@@ -1336,6 +1339,9 @@
             "version": "==3.3.1"
         },
         "setuptools-scm": {
+            "extras": [
+                "toml"
+            ],
             "hashes": [
                 "sha256:c3bd5f701c8def44a5c0bfe8d407bef3f80342217ef3492b951f3777bd2d915c",
                 "sha256:d1925a69cb07e9b29416a275b9fadb009a23c148ace905b2fb220649a6c18e92"

diff --git a/setup.py b/setup.py
index 929096a2098f97a6de86b2cb09b5e817a0a4ca60..19df9beb24eb8369250f8af7d2a915236e6528ea 100644 (file)
--- a/setup.py
+++ b/setup.py
@@ -86,7 +86,7 @@ setup(
         "mypy_extensions>=0.4.3",
     ],
     extras_require={
-        "d": ["aiohttp>=3.6.0", "aiohttp-cors>=0.4.0"],
+        "d": ["aiohttp>=3.6.0"],
         "colorama": ["colorama>=0.4.3"],
         "python2": ["typed-ast>=1.4.2"],
         "uvloop": ["uvloop>=0.15.2"],

diff --git a/src/blackd/__init__.py b/src/blackd/__init__.py
index d062303fd10d4f3190de861cfb5a4ddd42f2ac0a..cc966404a743a37bd2059c89732e7ad9d3b8b384 100644 (file)
--- a/src/blackd/__init__.py
+++ b/src/blackd/__init__.py
@@ -8,7 +8,7 @@ from typing import Set, Tuple
 
 try:
     from aiohttp import web
-    import aiohttp_cors
+    from .middlewares import cors
 except ImportError as ie:
     raise ImportError(
         f"aiohttp dependency is not installed: {ie}. "
@@ -67,20 +67,11 @@ def main(bind_host: str, bind_port: int) -> None:
 
 
 def make_app() -> web.Application:
-    app = web.Application()
-    executor = ProcessPoolExecutor()
-
-    cors = aiohttp_cors.setup(app)
-    resource = cors.add(app.router.add_resource("/"))
-    cors.add(
-        resource.add_route("POST", partial(handle, executor=executor)),
-        {
-            "*": aiohttp_cors.ResourceOptions(
-                allow_headers=(*BLACK_HEADERS, "Content-Type"), expose_headers="*"
-            )
-        },
+    app = web.Application(
+        middlewares=[cors(allow_headers=(*BLACK_HEADERS, "Content-Type"))]
     )
-
+    executor = ProcessPoolExecutor()
+    app.add_routes([web.post("/", partial(handle, executor=executor))])
     return app
 
 

diff --git a/src/blackd/middlewares.py b/src/blackd/middlewares.py
new file mode 100644 (file)
index 0000000..97994ec
--- /dev/null
+++ b/src/blackd/middlewares.py
@@ -0,0 +1,34 @@
+from typing import Iterable, Awaitable, Callable
+from aiohttp.web_response import StreamResponse
+from aiohttp.web_request import Request
+from aiohttp.web_middlewares import middleware
+
+Handler = Callable[[Request], Awaitable[StreamResponse]]
+Middleware = Callable[[Request, Handler], Awaitable[StreamResponse]]
+
+
+def cors(allow_headers: Iterable[str]) -> Middleware:
+    @middleware
+    async def impl(request: Request, handler: Handler) -> StreamResponse:
+        is_options = request.method == "OPTIONS"
+        is_preflight = is_options and "Access-Control-Request-Method" in request.headers
+        if is_preflight:
+            resp = StreamResponse()
+        else:
+            resp = await handler(request)
+
+        origin = request.headers.get("Origin")
+        if not origin:
+            return resp
+
+        resp.headers["Access-Control-Allow-Origin"] = "*"
+        resp.headers["Access-Control-Expose-Headers"] = "*"
+        if is_options:
+            resp.headers["Access-Control-Allow-Headers"] = ", ".join(allow_headers)
+            resp.headers["Access-Control-Allow-Methods"] = ", ".join(
+                ("OPTIONS", "POST")
+            )
+
+        return resp
+
+    return impl  # type: ignore

diff --git a/tests/test_blackd.py b/tests/test_blackd.py
index 9ca19d49dc6b79a86314100a0e37e3df23f16e58..cc750b40567d7c4c0f393a272780f41115162b4e 100644 (file)
--- a/tests/test_blackd.py
+++ b/tests/test_blackd.py
@@ -164,3 +164,24 @@ class BlackDTestCase(AioHTTPTestCase):
     async def test_blackd_response_black_version_header(self) -> None:
         response = await self.client.post("/")
         self.assertIsNotNone(response.headers.get(blackd.BLACK_VERSION_HEADER))
+
+    @unittest_run_loop
+    async def test_cors_preflight(self) -> None:
+        response = await self.client.options(
+            "/",
+            headers={
+                "Access-Control-Request-Method": "POST",
+                "Origin": "*",
+                "Access-Control-Request-Headers": "Content-Type",
+            },
+        )
+        self.assertEqual(response.status, 200)
+        self.assertIsNotNone(response.headers.get("Access-Control-Allow-Origin"))
+        self.assertIsNotNone(response.headers.get("Access-Control-Allow-Headers"))
+        self.assertIsNotNone(response.headers.get("Access-Control-Allow-Methods"))
+
+    @unittest_run_loop
+    async def test_cors_headers_present(self) -> None:
+        response = await self.client.post("/", headers={"Origin": "*"})
+        self.assertIsNotNone(response.headers.get("Access-Control-Allow-Origin"))
+        self.assertIsNotNone(response.headers.get("Access-Control-Expose-Headers"))