Hello, i'm trying to use custom blocks and i got errors with my code, and finally, if i try with the example given by the documentation , i get the same error which is :

ValueError: Value not declarable with JSON Schema, field: name='aws_secret_access_key' type=Optional[SecretStr] required=False default=None

Example code (you'll see a previous error i had to fix) :

from typing import Optional

from prefect.blocks.core import Block
from pydantic import SecretStr

class AWSCredentials(Block):
    aws_access_key_id: Optional[str] = None
    aws_secret_access_key: Optional[SecretStr] = None
    aws_session_token: Optional[str] = None
    profile_name: Optional[str] = None
    region_name: Optional[str] = None
    
    # To prevent "RuntimeError: no validator found for <class 'pydantic.types.SecretStr'>, see `arbitrary_types_allowed` in Config"
    class Config:
        arbitrary_types_allowed = True

aws_credentials_block = AWSCredentials(
    aws_access_key_id="AKIAJKLJKLJKLJKLJKLJK",
    aws_secret_access_key="secret_access_key"
)

print(aws_credentials_block)

I hope someone could help me 🙂 Thank you

hi serial, i think the problem is that your snippet above is using a pydantic v2 object. (

SecretStr

) in one of our pydantic v1 only classes (

Block

) can you try updating this line in your snippet above

from pydantic import SecretStr

to

from pydantic.v1 import SecretStr

?

Hello, thank you, it works well ! Otherwise, i could force the pydantic version during pip install ?

yes! if you pin pydantic to v1 then your original snippet should work just fine

Thanks for the information