TypeError: int() argument must be a string, a bytes-like object or a number, not 'InstrumentedAttribute' about flask_accepts

[apryor6]

Not a problem, glad you got it resolved!

[ibLeDy]

Hi, do you have any info on this?
Thanks!

[apryor6]

I've not been able to replicate this. Could you provide a code snippet that reproduces the issue so that I can take a look?

[ibLeDy]

I have basically the same structure as flask_api_example has, but i changed fields.Number in schema to fields.Integer, at first i thought that could be the issue but can't replicate doing the same in your example. It could be possible that it is my fault, but couldn't find the issue. Excuse me if that's the case, i don't have much experience at programming and i don't fully understand how the abstractions and interactions between the layers are.

I don't know which parts do you need to take a look at, sorry for the long comment.

• app/barbota/ranks/schema.py

from marshmallow import fields, Schema

class RanksSchema(Schema):
    """Barbota Ranks schema"""

    rankId = fields.Integer(attribute="rank_id")
    rankName = fields.String(attribute="rank_name")
    skinName = fields.String(attribute="skin_name")
    levelNeeded = fields.Integer(attribute="level_needed")
    hpGain = fields.Integer(attribute="hp_gain")
    dmgGain = fields.Integer(attribute="dmg_gain")
    curationGain = fields.Integer(attribute="curation_gain")
    armorGain = fields.Integer(attribute="armor_gain")
    price = fields.Integer(attribute="price")
    userCount = fields.Integer(attribute="user_count")

• app/barbota/ranks/model.py

from sqlalchemy import Integer, Column, String
from app import db  # noqa
from .interface import RanksInterface
from typing import Any

class Ranks(db.Model):  # type: ignore
    """A Rank"""

    __tablename__ = "ranks"

    rank_id = Column(Integer(), primary_key=True)
    rank_name = Column(String(255))
    skin_name = Column(String(255))
    level_needed = Column(Integer())
    hp_gain = Column(Integer())
    dmg_gain = Column(Integer())
    curation_gain = Column(Integer())
    armor_gain = Column(Integer())
    price = Column(Integer())
    user_count = Column(Integer())

    def update(self, changes: RanksInterface):
        for key, val in changes.items():
            setattr(self, key, val)
        return self

• app/barbota/ranks/interface.py

from mypy_extensions import TypedDict

class RanksInterface(TypedDict, total=False):
    rank_id: int
    rank_name: str
    skin_name: str
    level_needed: int
    hp_gain: int
    dmg_gain: int
    curation_gain: int
    armor_gain: int
    price: int
    user_count: int

• app/barbota/ranks/controller.py

    @accepts(schema=RanksSchema, api=api)
    @responds(schema=RanksSchema)
    def put(self, rankId: int) -> Ranks:
        """Update Rank"""
        try:
            if request.headers["Apikey"] != API_KEY:
                api.abort(403)
        except KeyError:
            api.abort(403)

        changes: RanksInterface = request.parsed_obj
        Ranks = RanksService.get_by_id(rankId)
        return RanksService.update(Ranks, changes)

• app/barbota/ranks/service.py

    @staticmethod
    def update(ranks: Ranks, Ranks_change_updates: RanksInterface) -> Ranks:
        ranks.update(Ranks_change_updates)
        db.session.commit()
        return Ranks

• example table contents (/api/barbota/ranks/)

[
  {
    "price": 0,
    "curationGain": 0,
    "hpGain": 0,
    "rankId": 1,
    "dmgGain": 0,
    "skinName": "barbita",
    "armorGain": 0,
    "rankName": "Recluta",
    "userCount": 0,
    "levelNeeded": 0
  },
  {
    "price": 0,
    "curationGain": 0,
    "hpGain": 0,
    "rankId": 2,
    "dmgGain": 0,
    "skinName": "barbita",
    "armorGain": 0,
    "rankName": "Ayudante",
    "userCount": 0,
    "levelNeeded": 5
  },
  {
    "price": 10000,
    "curationGain": 0,
    "hpGain": 0,
    "rankId": 3,
    "dmgGain": 0,
    "skinName": "barbita",
    "armorGain": 0,
    "rankName": "Aspirante",
    "userCount": 0,
    "levelNeeded": 10
  }
]

• put request to: /api/barbota/ranks/1

{
    "price": 0,
    "curationGain": 0,
    "hpGain": 0,
    "rankId": 1,
    "dmgGain": 0,
    "skinName": "barbita",
    "armorGain": 0,
    "rankName": "Recluta",
    "userCount": 0,
    "levelNeeded": 0
}

• response body (500 Error: INTERNAL SERVER ERROR)

{
  "message": "Internal Server Error"
}

• response headers

connection: keep-alive
content-length: 37
content-type: application/json
date: Wed, 18 Dec 2019 17:39:41 GMT
server: gunicorn/19.9.0
vary: Origin
via: 1.1 vegur 

• traceback (heroku, cleaner in original issue comment)

2019-12-18T17:43:17.932906+00:00 app[web.1]: [2019-12-18 17:43:17,932] ERROR in app: Exception on /api/barbota/ranks/1 [PUT]
2019-12-18T17:43:17.932938+00:00 app[web.1]: Traceback (most recent call last):
2019-12-18T17:43:17.932940+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask/app.py", line 1949, in full_dispatch_request
2019-12-18T17:43:17.932941+00:00 app[web.1]: rv = self.dispatch_request()
2019-12-18T17:43:17.932943+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask/app.py", line 1935, in dispatch_request
2019-12-18T17:43:17.932945+00:00 app[web.1]: return self.view_functions[rule.endpoint](**req.view_args)
2019-12-18T17:43:17.932946+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask_restplus/api.py", line 325, in wrapper
2019-12-18T17:43:17.932948+00:00 app[web.1]: resp = resource(*args, **kwargs)
2019-12-18T17:43:17.932949+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask/views.py", line 89, in view
2019-12-18T17:43:17.932951+00:00 app[web.1]: return self.dispatch_request(*args, **kwargs)
2019-12-18T17:43:17.932953+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask_restplus/resource.py", line 44, in dispatch_request
2019-12-18T17:43:17.932954+00:00 app[web.1]: resp = meth(*args, **kwargs)
2019-12-18T17:43:17.932955+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask_accepts/decorators/decorators.py", line 100, in inner
2019-12-18T17:43:17.932956+00:00 app[web.1]: return func(*args, **kwargs)
2019-12-18T17:43:17.932958+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/flask_accepts/decorators/decorators.py", line 186, in inner
2019-12-18T17:43:17.932959+00:00 app[web.1]: serialized = schema.dump(rv)
2019-12-18T17:43:17.932960+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/marshmallow/schema.py", line 553, in dump
2019-12-18T17:43:17.932962+00:00 app[web.1]: result = self._serialize(processed_obj, many=many)
2019-12-18T17:43:17.932963+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/marshmallow/schema.py", line 517, in _serialize
2019-12-18T17:43:17.932965+00:00 app[web.1]: value = field_obj.serialize(attr_name, obj, accessor=self.get_attribute)
2019-12-18T17:43:17.932966+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/marshmallow/fields.py", line 325, in serialize
2019-12-18T17:43:17.932968+00:00 app[web.1]: return self._serialize(value, attr, obj, **kwargs)
2019-12-18T17:43:17.932969+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/marshmallow/fields.py", line 899, in _serialize
2019-12-18T17:43:17.932970+00:00 app[web.1]: ret = self._format_num(value)  # type: _T
2019-12-18T17:43:17.932971+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/marshmallow/fields.py", line 874, in _format_num
2019-12-18T17:43:17.932973+00:00 app[web.1]: return self.num_type(value)
2019-12-18T17:43:17.932979+00:00 app[web.1]: TypeError: int() argument must be a string, a bytes-like object or a number, not 'InstrumentedAttribute'

[ibLeDy]

Hey, i was able to figure out the issue, it was my mistake.
I was returning Ranks instead of ranks in service.py ...

So sorry for wasting your time and thanks.