Add chain_id when building transaction

[dimitarvp]

Task list

• Add chain_id to Builder
• Fix bug when decoding the chain_id -- allow it to be larger than one byte
• Add chain_id to Signer

[dimitarvp]

I started getting this error when working with Polygon Mumbai (Polygon testnet):

%{"code" => -32000, "message" => "only replay-protected (EIP-155) transactions allowed over RPC"}

I tried adding the chain_id to the builder but it seems it's not enough. @izelnakri I'll try modify the transaction signer as well. This PR is not ready for merge.

[dimitarvp]

This commit -- 5c3860f -- allows the encoded chain_id be more than 1 byte.

The previous code fails when chain_id is 80001 (Polygon Mumbai (testnet)):

<<number>> = to_buffer(data)

(data in this case is <<2, 113, 37>>, which is 2*80001 + 35 encoded as bytes; this is required by EIP-155)

But by using this:

data |> to_buffer() |> :binary.decode_unsigned()

We allow the result to be an arbitrarily long integer (as EIP-155 specifies).

[dimitarvp]

Link to EIP-155: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-155.md

[izelnakri]

The changes so far looks good to me, I’ll read your comments in depth ;)

Meanwhile Im thinking we might want to improve/refactor CI to use openethereum first, what do you think?

[dimitarvp]

I know nothing about it so far. Could read on it after this is completed.

[dimitarvp]

This is not ready for merge, no need to approve yet. I'll appreciate help on fixing the signer code -- although I am working on it myself and should be done soon.

[quangacuity]

This is not ready for merge, no need to approve yet. I'll appreciate help on fixing the signer code -- although I am working on it myself and should be done soon.

Hi @dimitarvp, any updates on this?

I'm trying to continue with your work here quangacuity@48639ba. But this doesn't seem to be enough as I get this error now when trying to send the signed transaction.

{:error, %{"code" => -32000, "message" => "invalid sender"}}

@izelnakri Do you have any suggestions on how to make this work for ETH.Transaction.Signer?

Many thanks.

Edited: Ok I manage to get it working by this commit.

[izelnakri]

Hi @quangacuity , we need to change the CI entirely, it currently uses ganache-cli but I'd much rather like to use the test environment of openethereum first. Because we had mismatches in the past. at least relying on a real implementation/production code is what we should strive for going forward.