eip712

0.3.3 verified Fri May 01 auth: no python

Message classes for typed structured data hashing and signing in Ethereum, based on EIP-712. Current version 0.3.3, requires Python >=3.10, <4. Maintained actively by ApeWorX.

pip install eip712

Common errors

error ModuleNotFoundError: No module named 'eip712' ↓

cause Library not installed.

fix

Run 'pip install eip712'

error ImportError: cannot import name 'EIP712Type' from 'eip712' ↓

cause EIP712Type was removed in version 0.3.0.

fix

Use pydantic models instead; or upgrade to a version <0.3.0 if you must use EIP712Type.

error ValidationError: 1 validation error for Mail from_ field required ↓

cause Field name 'from_' is used but pydantic treats it as a field name; likely missing alias.

fix

Define the field with an alias: from_: Person = Field(alias='from')

error AttributeError: 'EIP712Message' object has no attribute 'to_message' ↓

cause Method 'to_message' may not exist in older versions.

fix

Use 'encode_712()' or 'signable_message()' depending on needs. Check docstrings.

Warnings

breaking v0.3.0 replaced dataclassy with pydantic. If you subclasses EIP712Message directly, you need to adapt to pydantic behavior (e.g., field aliases, validation). ↓

fix Ensure you use pydantic field types and aliases instead of dataclassy patterns.

breaking In v0.3.0, EIP712Type was removed as a separate class. Inner types should be plain pydantic models or Python types. ↓

fix Remove EIP712Type subclass usage; define nested types as pydantic models directly.

gotcha Field names that conflict with Python keywords (e.g., 'from') must use pydantic aliasing with Field(alias=...). ↓

fix Use from eip712 import EIP712Message, Field; then define from_: str = Field(alias='from')

deprecated String type annotations like 'uint256' are deprecated; use pydantic numeric types (e.g., int, float) or custom validators. ↓

fix Replace 'uint256' with int and add pydantic validators if needed.

Imports

EIP712Message
```
from eip712 import EIP712Message
```
Correct import for the main message class.
EIP712Type
wrong
```
from eip712.messages import EIP712Type
```
correct
```
from eip712 import EIP712Type
```
EIP712Type is exported from top-level eip712 since v0.3.0.

EIP712Domain

wrong

from eip712.domain import EIP712Domain

correct

from eip712 import EIP712Domain

EIP712Domain is now directly available from eip712.

Quickstart

Define EIP-712 message structures using pydantic-based classes and generate the structured data for signing.

from eip712 import EIP712Message, EIP712Domain

class Person(EIP712Message):
    name: str
    wallet: str

class Mail(EIP712Message):
    from_: Person = Person(name='Alice', wallet='0x...')  # field alias
    to: Person
    contents: str

message = Mail(
    from_=Person(name='Alice', wallet='0x...'),
    to=Person(name='Bob', wallet='0x...'),
    contents='Hello!'
)
print(message.to_message())
print(message.encode_712())
print(message.signable_message())