Ability to get unsigned encoded RLP transaction

[antazoey]

What feature should we add?

I am struggling to get the unsigned encoded RLP transaction, before hash and before signing.
Like

02f843827a698080808094000000000000000000000000000000000000000080a4c8c57ba6eb886a56f9f0efa64432678cebf1270e9314a758e6eb697a606202a451e3e82ec0

this level of detail is just so hidden and abstracted away it becomes nearly impossible to find a decent API to get it without having to re-do everything this library does

looking at the hash method from dynamic tx

    def hash(self) -> bytes:
        """
        Hashes this DynamicFeeTransaction to prepare it for signing.
        As per the EIP-1559 specifications, the signature is a secp256k1 signature over
        ``keccak256(0x02 || rlp([chainId, nonce, maxPriorityFeePerGas,
        maxFeePerGas, gasLimit, to, value, data, accessList]))``
        """
        # Remove signature fields.
        transaction_without_signature_fields = dissoc(self.dictionary, "v", "r", "s")
        # RPC-structured transaction to rlp-structured transaction
        rlp_structured_txn_without_sig_fields = transaction_rpc_to_rlp_structure(
            transaction_without_signature_fields
        )
        rlp_serializer = self.__class__._unsigned_transaction_serializer
        hash = pipe(
            rlp_serializer.from_dict(rlp_structured_txn_without_sig_fields),  # type: ignore  # noqa: E501
            lambda val: rlp.encode(val),  # rlp([...])
            lambda val: bytes([self.__class__.transaction_type])
            + val,  # (0x02 || rlp([...]))
            keccak,  # keccak256(0x02 || rlp([...]))
        )
        return cast(bytes, hash)

i can see the value is need is buried in there somewhere, would be nice to have access to this

[antazoey]

I got the value I needed by doing this

        # TODO: delete this
        serializer = rlp_serializer.from_dict(rlp_structured_txn_without_sig_fields)
        val = rlp.encode(serializer)
        print(f"02{val.hex()}")