How to delete empty field?

Question

I have a BaseModel like this

from pydantic import BaseModel

class TestModel(BaseModel):
    id: int
    names: str = None

While I validate some data like this

TestModel(id=123).dict()

I got result

{'id': 123, 'name': None}

But what I expect is:

{'id': 123}

Question: Is there a method to delete empty field? Thanks!

I found a solution. First, give the field a default value `None`. Then, use ```TestModel(id=123).dict(exclude_none=True)``` to exclude it. — fallthrough, May 07 '20 at 05:56

score 39 · Accepted Answer · answered May 07 '20 at 08:14

39

The correct way to do this is with

TestModel(id=123).dict(exclude_none=True)

If you need this everywhere, you can override dict() and change the default.

answered May 07 '20 at 08:14

SColvin

1

Is this supported as an option within `BaseModel.Config`? Would be nice to see this as a declarative option. – Yaakov Bressler Nov 17 '22 at 03:08

score 7 · Answer 2 · answered Jul 05 '22 at 06:10

7

You can also set it in the model's Config so you don't have to keep writing it down:

class TestModel(BaseModel):
    id: int
    names: str = None

    class Config:
        fields = {'name': {'exclude': True}}

answered Jul 05 '22 at 06:10

enchance

score 0 · Answer 3 · answered May 07 '20 at 03:19

0

if you want to delete keys from a dictionary with value "None" :

result = {k: v for k, v in result.items() if v is not None }

answered May 07 '20 at 03:19

But everywhere use the validator must have this operate, and it is not related to logical code. Is it possible to complete it in validator?Thanks! – fallthrough May 07 '20 at 03:28

score 0 · Answer 4 · answered Mar 08 '22 at 15:23

0

you can perhaps add a root_validator:

@pydantic.root_validator(pre=False)
def check(cls, values):
    if values['some_key'] is None
        del values['some_key']

answered Mar 08 '22 at 15:23

DMA2607

4 Answers4