Incompatible with Sanic-21.12.0

[eric-spitler]

Sanic 21.12.0 was release on 12/26/2021 and has breaking changes.

Specifically, it makes setting of attributes on Sanic or Blueprint instances an error where it was previously a DeprecationWarning. The plugin toolkit tries to wrap Sanic._startup but setting its value, which raises an AttributeError.

Here is a sample section that will raise the AttributeError. This line is reached because in 21.12 the Sanic.__fake_slots__ became Sanic.__slots__.

sanic-plugin-toolkit/sanic_plugin_toolkit/realm.py

Lines 999 to 1001 in 646820c

	if hasattr(app, "_startup"):
	# We can wrap startup, to patch _after_ Touchup is done
	app._startup = update_wrapper(partial(self._startup, app, app._startup), app._startup)

Furthermore, Blueprint objects no longer have __fake_slots__ either, so this section also raises AttributeError

sanic-plugin-toolkit/sanic_plugin_toolkit/realm.py

Lines 927 to 932 in 646820c

	if SANIC_21_3_0 <= SANIC_VERSION:
	_slots = list(Blueprint.__fake_slots__)
	_slots.extend(["register"])
	Sanic.__fake_slots__ = tuple(_slots)
	bp.register = update_wrapper(partial(bp_register, bp, bp.register), bp.register)
	setattr(bp.ctx, APP_CONFIG_INSTANCE_KEY, self)

[damianj]

I am also experiencing issues with this when trying to use the sanic-cors extension. Minimal reproducible code below:

from sanic import Sanic
from sanic_cors import CORS

app = Sanic("test_app")
CORS(app)


@app.route('/')
async def test(request):
    return "Hello world"

if __name__ == '__main__':
    app.run()

Results in:

AttributeError: Setting variables on Sanic instances is not allowed. You should change your Sanic instance to use instance.ctx._startup instead.

Python 3.10
sanic==21.12.0
sanic-plugin-toolkit==1.2.0
sanic-routing==0.7.2
sanic-cors==1.0.1

[ashleysommer]

Hi @eric-spitler and @damianj
I want to let you know, I am aware of the issue, I know of the problem and why it exists.

Unfortunately it looks like the methods that Sanic-Plugin-Toolkit uses to hook into Sanic will no longer be supported, and a new mechanism will need to be developed to work on Sanic 21.12 and above. I am currently working on that.

In the meantime, I am going to modify popular plugins (eg, Sanic-CORS) to no longer use Sanic-Plugin-Toolkit, and use the new Sanic features including the new extension mechanism, app context, request context, directly without needing the toolkit.

[ashleysommer]

@eric-spitler and @damianj
If you simply need support for Sanic-CORS, please see I've released Sanic-CORS v2.0, which no longer uses Sanic-Plugin-Toolkit, and it now works with Sanic v21.12.0.

[notzippy]

Hi @ashleysommer appreciate your work, this issue is also in sanic-restplus as well

[ashleysommer]

Hi @notzippy
Yes, I'm aware this affects Sanic restplus too.
I am working on a new version of Sanic Plugin Toolkit that will work with Sanic 21.12, but there are some big changes, it's a difficult job.

Besides that, there are some other reasons that Sanic-Restplus will not work on Sanic 21.12 yet. Sanic Restplus has a very low install base, so it's not high on my priority like like eg. Sanic-CORS.

I suggest stay on Sanic v21.9.x if you need to use Sanic-Restplus, that's what I have running in my prod deployments.