How to generate openapi specification without running the app?

[iamvishalkhare]

Need help/suggestion here. Use case - I am trying to use openapi.json file during CI pipeline execution. I need to upload it somewhere for further use. openapi.json file is generated at run time and served at http://0.0.0.0:8090/docs/openapi.json I can't run the app during CI pipeline execution due to other dependencies and it seems like a security issue as well.

Can someone please help here on how can I generate openapi.json file without actually running the app? @ahopkins

[ahopkins]

Wow, I am not sure this would be easy to do. Sure, it's Python so everything should be possible. But it will take quite a bit of hacking. You would need to instantiate your Sanic app, attach all your routes and blueprints, then attach the blueprint using the blueprint factory which has some startup time methods to build the spec, setup and finalize the router, and ultimate calling:

SpecificationBuilder().build(app).serialize()

Sanic is not really meant for offline usage, and the spec builder certainly not. To do this you are probably going to be calling a lot of lower level functions that are considered private and might break on new releases.

You are probably much better off running your app in CI with something like this:

from sanic_ext.extensions.openapi.builders import SpecificationBuilder
from ujson import dumps
from pathlib import Path

@app.after_server_start
async def build_spec(app):
    spec = SpecificationBuilder().build(app).serialize()
    Path("/some/location/spec.json").write_text(dumps(spec))
    app.stop()

[iamvishalkhare]

Thanks @ahopkins.. Life saver :)