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[Dashing-Nelson]

Hello,
I am trying to work on a project, and I am facing an issue.
The problem is that when I am requesting a resource from the server, google chrome is saying that the "Access-Control-Allow-Origin' header contains multiple values"
This is my code

@asyncio.coroutine
def handler(request):
    return web.Response(
        text="Hello!",
        headers={
            "X-Custom-Server-Header": "Custom data",
        })


app = web.Application()

cors = aiohttp_cors.setup(app)

resource = cors.add(app.router.add_resource("/"))

route = cors.add(
    resource.add_route("POST", handler), {
        "*": aiohttp_cors.ResourceOptions(allow_methods="*",
                                          allow_headers=("X-Requested-With", "Content-Type", "AUTHORIZATION"),
                                          expose_headers="*",
                                          allow_credentials=False
                                          )
    })
if __name__ == '__main__':
    web.run_app(app, port=os.getenv("PORT"), host='0.0.0.0')

i am serving aiohttp over nginx

[asvetlov]

Do you have a stack trace?