René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Update http module to return \"408 - Request timeout\"- when closing idle TCP connections.","articleBody":"**Is your feature request related to a problem? YES**\r\n\r\nCurrently, http implementation results in random HTTP errors, as a result of race conditions when closing idle connections.\r\n\r\nNode closes idle TCP connections after 5 seconds (configurable using `server.keepAliveTimeout`),\r\nresulting in a race conditions described at: [https://nodejs.org/api/http.html#http_request_reusedsocket]()\r\n\r\nThis documentation proposes request might be retried when receiving a `ECONNRESET` error, and that's what\r\nbrowsers do. However, this is not applicable when working with API Gateways, which can't close a downstream\r\nconnection (shared by multiple services) when an upstream connection is closed.\r\nInstead, Gateways return a 503 error code when an upstream connection is closed, resulting in a HTTP error.\r\nAdditional info [here](https://medium.com/@phylake/why-idle-timeouts-matter-1b3f7d4469fe).\r\n\r\nThe solution would be to configure `server.keepAliveTimeout` to be larger than the client. But Chrome keeps idle connections open for 5 to 6 minutes (according to [link](https://bugs.chromium.org/p/chromium/issues/detail?id=27400), up to 10 minutes). Using such a long timeout in the cloud  might not be a good idea.\r\n\r\n**Proposed solution**\r\n[RFC7231#6.5.7](https://datatracker.ietf.org/doc/html/rfc7231#section-6.5.7) and [Mozilla](https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/408) specify that servers MAY/SHOULD send a `408 – Request Timeout` response when closing idle connections, _even without a previous request from the server_. This would make any further request (if any) to receive a 408 error and would be automatically retried by the browser.\r\n\r\nNotice that, when using CORS, 408 response MUST include CORS headers (`Access-Control-Allow-Origin: *`).\r\n\r\nCurrently, there's no simple way to update http module, to return a 408 error when closing idle connections.\r\n\r\nI propose updating http module, to allow handling the idle-connection close event. Eg:\r\n```\r\nserver.on('idle', socket => {\r\n  socket.write('408 - Request timeout\\r\\nConnection: close\\r\\nAccess-Control-Allow-Origin: *\\r\\n\\r\\n');\r\n  socket.close();\r\n});\r\n```\r\n\r\n**Alternative solution**\r\nThis feature could also be an option, when creating the HTTP server. Eg:\r\n```\r\nhttp.createServer({ reply408WhenClosingIdleConnections: true }, handler);\r\n```\r\n","author":{"url":"https://github.com/gpra","@type":"Person","name":"gpra"},"datePublished":"2021-06-01T15:08:40Z","url":"https://github.com/nodejs/node/issues/38890"}