fastapi

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import pytest
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from fastapi import FastAPI, HTTPException
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from fastapi.exceptions import RequestValidationError
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from fastapi.testclient import TestClient
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from starlette.responses import JSONResponse
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def http_exception_handler(request, exception):
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    return JSONResponse({"exception": "http-exception"})
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def request_validation_exception_handler(request, exception):
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    return JSONResponse({"exception": "request-validation"})
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def server_error_exception_handler(request, exception):
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    return JSONResponse(status_code=500, content={"exception": "server-error"})
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app = FastAPI(
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    exception_handlers={
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        HTTPException: http_exception_handler,
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        RequestValidationError: request_validation_exception_handler,
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        Exception: server_error_exception_handler,
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    }
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)
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client = TestClient(app)
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@app.get("/http-exception")
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def route_with_http_exception():
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    raise HTTPException(status_code=400)
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@app.get("/request-validation/{param}/")
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def route_with_request_validation_exception(param: int):
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    pass  # pragma: no cover
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@app.get("/server-error")
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def route_with_server_error():
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    raise RuntimeError("Oops!")
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def test_override_http_exception():
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    response = client.get("/http-exception")
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    assert response.status_code == 200
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    assert response.json() == {"exception": "http-exception"}
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def test_override_request_validation_exception():
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    response = client.get("/request-validation/invalid")
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    assert response.status_code == 200
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    assert response.json() == {"exception": "request-validation"}
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def test_override_server_error_exception_raises():
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    with pytest.raises(RuntimeError):
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        client.get("/server-error")
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def test_override_server_error_exception_response():
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    client = TestClient(app, raise_server_exceptions=False)
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    response = client.get("/server-error")
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    assert response.status_code == 500
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    assert response.json() == {"exception": "server-error"}
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