{"id": 1496652622, "node_id": "I_kwDOBm6k_c5ZNRtO", "number": 1955, "title": "invoke_startup() is not run in some conditions, e.g. gunicorn/uvicorn workers, breaking lots of things", "user": {"value": 32839123, "label": "Rik-de-Kort"}, "state": "closed", "locked": 0, "assignee": null, "milestone": null, "comments": 36, "created_at": "2022-12-14T13:39:56Z", "updated_at": "2022-12-19T04:34:16Z", "closed_at": "2022-12-18T02:45:18Z", "author_association": "NONE", "pull_request": null, "body": "In the past (pre-september 14, #1809) I had a running deployment of Datasette on Azure WebApps by emulating the call in cli.py to Gunicorn: `gunicorn -w 2 -k uvicorn.workers.UvicornWorker app:app`.\r\n\r\nMy most recent deployment, however, fails loudly by shouting that `Datasette.invoke_startup()` was not called. It does not seem to be possible to call `invoke_startup` when running using a uvicorn command directly like this (I've reproduced this locally using `uvicorn`).  Two candidates that I have tried:\r\n* Uvicorn has a `--factory` option, but the app factory has to be synchronous, so no `await invoke_startup` there\r\n* `asyncio.get_event_loop().run_until_complete` is also not an option because `uvicorn` already has the event loop running.\r\n\r\nOne additional option is:\r\n* Use Gunicorn's [server hooks](https://docs.gunicorn.org/en/stable/settings.html#server-hooks) to call `invoke_startup`. These are also synchronous, but I might be able to get ahead of the event loop starting here.\r\n\r\nIn my current deployment setup, it does not appear to be possible to use `datasette serve` directly, so I'm stuck either\r\n* Trying to rework my complete deployment setup, for instance, using Azure functions as described [here](https://github.com/simonw/azure-functions-datasette))\r\n* Or dig into the ASGI spec and write a wrapper for the sole purpose of launching Datasette using a direct Uvicorn invocation.\r\n\r\nQuestions for the maintainers:\r\n* Is this intended behaviour/will not support/etc.? If so, I'd be happy to add a PR with a couple lines in the documentation.\r\n* if this is not intended behaviour, what is a good way to fix it? I could have a go at the ASGI spec thing (I think the Azure Functions thing is related) and provide a PR with the wrapper here, but I'm all ears!\r\n\r\nAlmost forgot, minimal reproducer:\r\n```python\r\nfrom datasette import Datasette\r\n\r\nds = Datasette(files=['./global-power-plants.db'])]\r\napp = ds.app()\r\n```\r\n\r\nSave as app.py in the same folder as global-power-plants.db, and then try running\r\n`uvicorn app:app`.\r\n\r\nOpening the resulting Datasette instance in the browser will show the error message.", "repo": {"value": 107914493, "label": "datasette"}, "type": "issue", "active_lock_reason": null, "performed_via_github_app": null, "reactions": "{\"url\": \"https://api.github.com/repos/simonw/datasette/issues/1955/reactions\", \"total_count\": 0, \"+1\": 0, \"-1\": 0, \"laugh\": 0, \"hooray\": 0, \"confused\": 0, \"heart\": 0, \"rocket\": 0, \"eyes\": 0}", "draft": null, "state_reason": "completed"}