add test

tests/test_depends_limiter.py

@@ -0,0 +1,125 @@
+from contextlib import asynccontextmanager
+import threading
+
+from fastapi import Depends, FastAPI
+from fastapi.testclient import TestClient
+from typing_extensions import Annotated
+import anyio
+import sniffio
+
+
+def get_borrowed_tokens():
+    return {
+        lname: l.borrowed_tokens
+        for lname, l in sorted(limiters.items())
+    }
+
+def limited_dep():
+    # run this in the event loop thread:
+    tokens = anyio.from_thread.run_sync(get_borrowed_tokens)
+    yield tokens
+
+
+def init_limiters():
+    return {
+        'default': None, # should be set in Lifespan handler
+        'a': anyio.CapacityLimiter(5),
+        'b': anyio.CapacityLimiter(3),
+    }
+
+# Note:
+# initializing CapacityLimiters at module level before the event loop has started
+# needs anyio >= 4.2.0; starlette currently requires anyio >= 3.4.0
+# see https://github.com/agronholm/anyio/pull/651
+
+# The following is a temporary workaround for anyio < 4.2.0:
+try:
+    limiters = init_limiters()
+except sniffio.AsyncLibraryNotFoundError:
+    # not in an async context yet
+    async def _init_limiters():
+        return init_limiters()
+    limiters = anyio.run(_init_limiters)
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    limiters['default'] = anyio.to_thread.current_default_thread_limiter()
+    yield {
+        'limiters': limiters,
+    }
+
+app = FastAPI(lifespan=lifespan)
+
+
+@app.get("/")
+async def root(borrowed_tokens: Annotated[dict, Depends(limited_dep)]):
+    return borrowed_tokens
+
+@app.get("/a")
+async def a(borrowed_tokens: Annotated[dict, Depends(limited_dep, limiter=limiters['a'])]):
+    return borrowed_tokens
+
+@app.get("/b")
+async def b(borrowed_tokens: Annotated[dict, Depends(limited_dep, limiter=limiters['b'])]):
+    return borrowed_tokens
+
+
+
+def test_depends_limiter():
+    with TestClient(app) as client:
+        response = client.get("/")
+        assert response.status_code == 200, response.text
+        assert response.json() == {"a":0,"b":0,"default":1}
+
+        response = client.get("/a")
+        assert response.status_code == 200, response.text
+        assert response.json() == {"a":1,"b":0,"default":0}
+
+        response = client.get("/b")
+        assert response.status_code == 200, response.text
+        assert response.json() == {"a":0,"b":1,"default":0}
+
+
+def test_openapi_schema():
+    with TestClient(app) as client:
+        response = client.get("/openapi.json")
+        assert response.status_code == 200, response.text
+        assert response.json()['paths'] == {
+            '/': {
+                'get': {
+                    'summary': 'Root',
+                    'operationId': 'root__get',
+                    'responses': {
+                        '200': {
+                            'description': 'Successful Response',
+                            'content': {'application/json': {'schema': {}}}
+                        }
+                    }
+                }
+            },
+            '/a': {
+                'get': {
+                    'summary': 'A',
+                    'operationId': 'a_a_get',
+                    'responses': {
+                        '200': {
+                            'description': 'Successful Response',
+                            'content': {'application/json': {'schema': {}}}
+                        }
+                    }
+                }
+            },
+            '/b': {
+                'get': {
+                    'summary': 'B',
+                    'operationId': 'b_b_get',
+                    'responses': {
+                        '200': {
+                            'description': 'Successful Response',
+                            'content': {'application/json': {'schema': {}}}
+                        }
+                    }
+                }
+            }
+        }