id,node_id,number,title,user,user_label,state,locked,assignee,assignee_label,milestone,milestone_label,comments,created_at,updated_at,closed_at,author_association,pull_request,body,repo,repo_label,type,active_lock_reason,performed_via_github_app,reactions,draft,state_reason
1496652622,I_kwDOBm6k_c5ZNRtO,1955,"invoke_startup() is not run in some conditions, e.g. gunicorn/uvicorn workers, breaking lots of things",32839123,Rik-de-Kort,closed,0,,,,,36,2022-12-14T13:39:56Z,2022-12-19T04:34:16Z,2022-12-18T02:45:18Z,NONE,,"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`.

My 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:
* Uvicorn has a `--factory` option, but the app factory has to be synchronous, so no `await invoke_startup` there
* `asyncio.get_event_loop().run_until_complete` is also not an option because `uvicorn` already has the event loop running.

One additional option is:
* 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.

In my current deployment setup, it does not appear to be possible to use `datasette serve` directly, so I'm stuck either
* Trying to rework my complete deployment setup, for instance, using Azure functions as described [here](https://github.com/simonw/azure-functions-datasette))
* Or dig into the ASGI spec and write a wrapper for the sole purpose of launching Datasette using a direct Uvicorn invocation.

Questions for the maintainers:
* 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.
* 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!

Almost forgot, minimal reproducer:
```python
from datasette import Datasette

ds = Datasette(files=['./global-power-plants.db'])]
app = ds.app()
```

Save as app.py in the same folder as global-power-plants.db, and then try running
`uvicorn app:app`.

Opening the resulting Datasette instance in the browser will show the error message.",107914493,datasette,issue,,,"{""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}",,completed