sign_seismic_tx_eip712

Sign and serialize TxSeismic using EIP-712 hashing

Sign and serialize a Seismic transaction using EIP-712 typed data hashing. This is the primary signing function for message_version == 2 transactions.

Signature

def sign_seismic_tx_eip712(
    tx: UnsignedSeismicTx,
    private_key: PrivateKey,
) -> HexBytes

Parameters

Parameter	Type	Required	Description
tx	UnsignedSeismicTx	Yes	The unsigned Seismic transaction (should have message_version == 2)
private_key	PrivateKey	Yes	32-byte secp256k1 private key

Returns

Type	Description
HexBytes	Full signed transaction bytes (0x4a prefix + RLP) ready for eth_sendRawTransaction

Steps

1. Compute eip712_signing_hash(tx)

2. Sign with eth_keys.PrivateKey.sign_msg_hash()

3. Serialize with serialize_signed(tx, sig) — same RLP as raw signing

The RLP serialization is identical to raw signing mode; only the ECDSA message hash differs. The Seismic node checks message_version to determine which verification path to use.

EIP-712 vs raw signing

Aspect	EIP-712 (message_version=2)	Raw (message_version=0)
Signing hash	Structured EIP-712 hash	RLP hash of unsigned tx
Wallet support	Better UX (structured display)	Generic message signing
RLP output	Identical	Identical
Verification	Node uses EIP-712 path	Node uses raw path

Example

from seismic_web3 import sign_seismic_tx_eip712

signed_tx = sign_seismic_tx_eip712(unsigned_tx, private_key)
tx_hash = w3.eth.send_raw_transaction(signed_tx)

Warnings

• The function does not enforce message_version == 2; callers should set it appropriately

• Ensure expires_at_block hasn't passed before broadcasting

See Also

• eip712_signing_hash — computes the signing hash

• build_seismic_typed_data — build typed data dict for external signers

• UnsignedSeismicTx — input transaction type

• PrivateKey — signing key type