Ctrl + C cannot close aiohttp server if there is a stream running

[yunyuyuan]

I'm using aiohttp web server to stream my raspberrypi's camera,here is my handler:

    # ......
    def start(self):
        self.app = web.Application()
        self.app.add_routes([
            web.get('/', lambda r: self.index(r)),
            web.get('/stream', lambda r: self.gen_stream(r))
        ])
        self.app.on_shutdown.append(lambda app: self.destroy())
        web.run_app(self.app, host='0.0.0.0', port=self.port)

    async def gen_stream(self, request: web_request.Request):
        boundary = 'FRAME'
        resp = web.StreamResponse(status=200, headers={
            'Age': '0',
            'Cache-Control': 'no-cache, private',
            'Pragma': 'no-cache',
            'Content-Type': f'multipart/x-mixed-replace; boundary={boundary}'
        })
        try:
            await resp.prepare(request)
            while True:
                if request.transport.is_closing():
                    print('Server closing')
                    break
                with self.output.condition:
                    self.output.condition.wait()
                    frame = self.output.frame
                with MultipartWriter('image/jpeg', boundary=boundary) as writer:
                    writer.append(frame, headers={
                        'Content-Type': 'image/jpeg',
                        'Content-Length': str(len(frame))
                    })
                    await writer.write(resp, close_boundary=False)
                await resp.write(b"\r\n")
        except Exception as e:
            await resp.write_eof()
            return res

I found Ctrl + C cannot shutdown web server if there is a webpage is streaming, if I close that webpage, Ctrl + C will shudown the server after 5 seconds,but self.destroy() not been called.
How to close web server appropriately?