bson.errors.InvalidDocument: cannot encode object: Decimal('3.5'), of type: <class 'decimal.Decimal'>

[leonardoarbache]

I have the follow document structure:

{
 ...
  "resultado": [
    {
      "badges": [
        {
          "codigo": "123",
          "url_imagem": "https://docs.mongoengine.org/apireference.html#mongoengine.fields.URLField",
          "valor": 3,
          "nome": "123",
          "descricao": "123",
          "master": false,
          
    }
   }
  ]
}

I declared the badge document as:

from mongoengine import (
    EmbeddedDocument, fields,
    DynamicDocument
)
class Badge(EmbeddedDocument):
    codigo = fields.StringField(required=False)
    url_imagem = fields.URLField(required=True)
    valor = fields.DecimalField(
        min_value=0,
        max_value=100,
        required=True
    )
    nome = fields.StringField(required=True)
    descricao = fields.StringField(required=True)
    master = fields.BooleanField(required=True)

I made a filter to filter the DecimalField on the EmbeddedDocument Badge:

import django_mongoengine_filter as mongofilter

class RelatorioFilterSet(mongofilter.FilterSet):
        badge_valor = mongofilter.NumberFilter(
        name='resultado__badges__valor'
    )

I'm trying to do the following request:

127.0.0.1:8000/relatorios/?badge_valor=3.5

But i always receive this error:

bson.errors.InvalidDocument: cannot encode object: Decimal('3.5'), of type: <class 'decimal.Decimal'>

I've already tried and observed that:

• import Decimal128 from bson.decimal128 and save the decimalfield on the document with Decimal128('3.5') did not resolve the problem.
• On the django shell Relatorio.objects.filter(resultado__badges__valor=3.5) works fine.
• Somehow when i add some character to the filter param on the request it did not raise an error but return nothing (e.g: 127.0.0.1:8000/relatorios/?badge_valor=3.5g)

I don't know what i missing or if there's something wrong. Please, HELP!

[barseghyanartur]

@leonardoarbache:

Could you post here all the software versions/system info?

[leonardoarbache]

Do you mean my requirements ?

asgiref==3.3.1
beautifulsoup4==4.9.3
celery==5.0.5
certifi==2020.12.5
chardet==4.0.0
cycler==0.10.0
Django==3.1.3
django-filter==2.4.0
django-rest-framework-nested==0.0.1
djangorestframework==3.12.2
djangorestframework-jwt==1.11.0
django-mongoengine-filter==0.3.5
django-rest-framework-mongoengine==3.4.1
django-cors-headers==3.7.0
flake8==3.8.4
gunicorn==20.0.4
html5lib==1.1
idna==2.10
importlib-metadata==2.0.0
kiwisolver==1.3.1
lxml==4.6.2
Markdown==3.3.3
matplotlib==3.3.4
mccabe==0.6.1
mysql==0.0.2
mysqlclient==2.0.3
mongoengine==0.20.0
numpy==1.19.5
pandas==1.1.5
Pillow==8.1.0
psycopg2-binary==2.8.6
pycodestyle==2.6.0
pyflakes==2.2.0
PyJWT==1.7.1
PyMySQL==0.10.1
pyparsing==2.4.7
python-dateutil==2.8.1
python-decouple==3.4
python-pptx==0.6.18
pytz==2020.4
requests==2.25.1
redis==3.5.0
six==1.15.0
soupsieve==2.1
sqlparse==0.4.1
urllib3==1.26.3
webencodings==0.5.1
whitenoise==5.2.0
XlsxWriter==1.3.7
xlwt==1.3.0
zipp==3.4.0

[barseghyanartur]

Also version of the mongodb and Python would be handy.

[leonardoarbache]

@barseghyanartur i'm using python3.8.0 and for mongo i'm using an docker container mongo:latest.

[barseghyanartur]

Could you check which "latest" is it?

[leonardoarbache]

mongo version 4.4.5

[oussjarrousse]

I would like to work on this if it is still relevant. @leonardoarbache Still interested in a solution?

[leonardoarbache]

Yeah I'm still interested.
If you can help would be awesome, @oussjarrousse :)

[dolho]

I had a similar issue. The problem is with mongoengine not being able to handle decimals inside dicts properly, so I had to do following workaround and use float instead of decimal, which was sufficient for my use case:

import django_mongoengine_filter
from django import forms

class FloatFilter(django_mongoengine_filter.NumberFilter):
    field_class = forms.FloatField

And then than use it like this

import django_mongoengine_filter


from .helpers import FloatFilter


class MyFilter(django_mongoengine_filter.FilterSet):
    float_field = FloatFilter(name="float_field")