Create a model dynamically with create_model() specifying a subset of fields in V2 about pydantic HOT 8 OPEN

@tteguayco,

We can leave this open - it's a pretty heavily requested feature, so I think it'll be great to leave this open as a feature request. I'll work on an API design. I think this can fit into the scope of v2.9!

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@sydney-runkle

It should be a new model that doesn't include those fields at all.

I have tried something like:

exclude = [...]   ## An array with the names of those fields to exclude

for field_name in list(new_model.model_fields.keys()):
    if field_name in exclude:
        new_model.model_fields.get(field_name).exclude = True

and even:

exclude = [...]   ## An array with the names of those fields to exclude

for field_name in list(new_model.model_fields.keys()):
    if field_name in exclude:
        new_model.model_fields.pop(field_name)

but when using the newly-created model, the undesired fields are still there, and even populated.

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Yep, gotcha. This reminds me of #6699

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Thank you for your answer, @sydney-runkle.

After some back-and-forth attempts, marking the fields as exclude = True makes the new model have them also excluded.

for field_name in list(base_model.model_fields.keys()):
    if  field_name in exclude:
        base_model.model_fields.get(field_name).exclude = True

new_model = create_model('MyNewModel', __base__=base_model)

However, I'm really surprised Pydantic doesn't provide a method to exclude fields in an inherited model out of the box, instead of doing all of this handcrafting work.

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Thanks a lot, @sydney-runkle!

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Sorry for the mention, @sydney-runkle.

Do you know if there's a way of doing this? It's a little important for us.

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@tteguayco,

Do you want to exclude said fields just for serialization, or during validation as well?

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We can mark the above answer as the solution, at least for my specific problem.

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