[Bug] TypeError: Object of type Spec is not JSON serializable

[oalexandere]

Description
Trying to reproduce simple example with Getting Started code: https://sanic-openapi.readthedocs.io/en/latest/
When opens swager page see an error: Failed to load API definition.
With previous version sanic-openapi 0.6.0 everithing works fine.

Screenshot

To Reproduce

from sanic import Sanic
from sanic.response import json
from sanic_openapi import swagger_blueprint

app = Sanic()
app.blueprint(swagger_blueprint)


@app.route("/")
async def test(request):
    return json({"hello": "world"})

if __name__ == "__main__":
    app.run(host="0.0.0.0", port=8000)

Environment (please complete the following information):

• OS: Windows 10 x64
• Python: 3.7
• Browser: chrome 79.0.3948.88
• sanic-openapi: 0.6.1
• sanic: 19.12.2

Additional context

Traceback (most recent call last):
File "C:\Users\user.virtualenvs\bbscreener\lib\site-packages\sanic\app.py", line 974, in handle_request
response = handler(request, *args, **kwargs)
File "C:\Users\user.virtualenvs\bbscreener\lib\site-packages\sanic_openapi\swagger.py", line 263, in spec
return json(swagger_blueprint.spec)
File "C:\Users\user.virtualenvs\bbscreener\lib\site-packages\sanic\response.py", line 234, in json
dumps(body, **kwargs),
File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json_init.py", line 238, in dumps
**kw).encode(obj)
File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\encoder.py", line 199, in encode
chunks = self.iterencode(o, _one_shot=True)
File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\encoder.py", line 257, in iterencode
return _iterencode(o, 0)
File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\encoder.py", line 179, in default
raise TypeError(f'Object of type {o.class.name} '
TypeError: Object of type Spec is not JSON serializable

[AtomsForPeace]

Thanks for the good bug report. I'll take a look at this later on.

[AtomsForPeace]

I'm not able to reproduce this locally. What address are you going to?
Works for me at http://localhost:8000/swagger/#/default/test

[oalexandere]

Hello!
For reproducing I've create a new virtual env and installed only sanic-openapi (python --version 3.7.4):

Then run the app:

Goes http://127.0.0.1:8000/ and get {"hello":"world"}. But http://127.0.0.1:8000/swagger/ gets me an error:

Here is the app errors when I goes to http://127.0.0.1:8000/swagger/:

If I goes http://localhost:8000/swagger/#/default/test it also returns same errors:

[oalexandere]

If downgrade sanic-openapi version to 0.6 everything works fine:

[oalexandere]

Additional info, maybe it will be usefull.
Line 263 in swagger.py returns json(swagger_blueprint._spec), where swagger_blueprint._spec is Spec object, not dict as in version 0.6.0 sanic-openapi (rigth screen, line 289):

[chenjr0719]

It is because that ujson can dump Spec class to JSON but json can not. And your OS is windows so you can only use json. That is the reason I and @AtomsForPeace can not reproducible the bug. Let me think about how to fix it and thanks for your report. It is very helpful to improve this project. 😀

[AtomsForPeace]

@chenjr0719 Can we add CI for windows?

Maybe returning the json of the dict of the Spec class. I could try that but can't really test it... :/

[oalexandere]

Thank you for your response, I created a pull request with trying to fix it, look it please.

[chenjr0719]

@chenjr0719 Can we add CI for windows?

Maybe we can follow the same configuration from sanic to test without ujson. What do you think?

[chenjr0719]

The #157 has been merged. Close this issue.

[xnuinside]

btw, same issue 1-to-1 with 0.6.1 on MacOS 10.14.6, not only on Windows. Also solved problem with downgrade to 0.6.0 version.

[Ronserruya]

^^ Same issue on MacOs 10.15.1 , works when downgrading to 0.6.0

[garcia-0E]

I'm facing this issue on a local Ubuntu 19.04 env. Tried to downgrade to 0.6.0 but still, have any clue??

[chenjr0719]

@ray-t1 I think it is related to the new ujson release. Would you please try ujson==1.3.5 and check is this issue still exist? Somehow the new version of ujson changes its behavior and it affects the JSON serialization.

[GitHubLeoYeh]

After install ujson==1.35
Solve it!!
(Ubuntu 18.04.4 LTS )
thanks @chenjr0719

[dnutiu]

I can confirm that this bug is still happening; Downgrading to usjon==1.35 is not a solution, make silent bugs and memory leaks can occur. usjon==3.0.0 make the de-serialization stricter that's why exceptions occur, errors are no longer ignored.