Skip to content

ApeWorX/eth-pydantic-types

Repository files navigation

eth-pydantic-types

The types in this package are pydantic types for Ethereum inspired from eth-typing.

Hash

HashBytes{n} and HashStr{n} are good types to use when your hex values are sized. Both types serialize to string in the JSON schema. Use HashBytes types when you want types to serialize to bytes in the Pydantic core schema and HashStr types when you want to serialize to str in the core Pydantic schema.

from pydantic import BaseModel

from eth_pydantic_types import HashBytes32, HashStr20

# When serializing to JSON, both types are hex strings.
class Transaction(BaseModel):
    tx_hash: HashBytes32  # Will be bytes
    address: HashStr20  # Will be str


# NOTE: I am able to pass an int-hash as the value and it will
#  get validated and type-coerced.
tx = Transaction(
    tx_hash=0x1031f0c9ac54dcb64b4f121a27957c14263c5cb49ed316d568e41e19c34d7b28,
    address=0x1031f0c9ac54dcb64b4f121a27957c14263c5cb4,
)

HexBytes

A thin-wrapper around an already thin-wrapper hexbytes.HexBytes. The difference here is that this HexBytes properly serializes. Use HexBytes any place where you would actually use hexbytes.HexBytes. HexBytes serializes to bytes in the Pydantic core schema and string in the JSON schema with a binary format.

from pydantic import BaseModel
from eth_pydantic_types import HexBytes

class MyStorage(BaseModel):
    cid: HexBytes

# NOTE: We are able to pass a hex-str for a HexBytes value.
storage = MyStorage(cid="0x123")

Address

Use the Address class for working with checksummed-addresses. Addresses get validated and checksummed in model construction. Addresses serialize to str in the Pydantic core schema and string in the JSON schema with a binary format.

from pydantic import BaseModel
from eth_pydantic_types import Address

class Account(BaseModel):
    address: Address

# NOTE: The address ends up checksummed
#   ("0x0837207e343277CBd6c114a45EC0e9Ec56a1AD84")
account = Account(address="0x837207e343277cbd6c114a45ec0e9ec56a1ad84")

HexStr

Use hex str when you only care about un-sized hex strings. The HexStr type serializes to str in the Pydantic core schema and a string in the JSON schema with a binary format.

from eth_pydantic_types import HexStr
from pydantic import BaseModel

class Tx(BaseModel):
    data: HexStr

tx = Tx(data="0x0123")

Bip122Uri

Use BIP-122 URIs in your models by annotating with the Bip122Uri type. This type serializes to a str in the Pydantic core schema as well as a string in the JSON schema, however the individual hashes are validated.

from eth_pydantic_types import Bip122Uri
from pydantic import BaseModel

class Message(BaseModel):
    path: Bip122Uri

message = Message(
    path=(
        "blockchain://d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3"
        "/block/752820c0ad7abc1200f9ad42c4adc6fbb4bd44b5bed4667990e64565102c1ba6"
    )
)