Add support Ethermint

[vincentysc]

Hi!

I added the Ethermint support to cosmjs locally with the following functions:

• generate EVM / Bech32 address from public key type /ethermint.crypto.v1.ethsecp256k1.PubKey
• sign the transaction with public key type /ethermint.crypto.v1.ethsecp256k1.PubKey

Is it ok to add a public key type flag to identify different decode/signing method in the following files? Any suggestions?

Generate address

In directsecp256k1hdwallet.js: getAccountsWithPrivkeys(), getKeyPair()
In account.js: accountFromAny()

Sign transaction

In pubkey.js: decodePubkey(), decodeSinglePubkey(), encodePubkey()
In signingstargateclient.js: signDirect()

[webmaster128]

👋 I'm not convinced we should add chain-specific types into any core component of the library. But let's see, maybe we can help here and there …

In account.js: accountFromAny()

Do you need support for your own account type? This was recently implemented in #1102

[vincentysc]

No problem~~

For generating the address, it's all good. I can do it outside the library and keep the core component library clean.

But for adding a new transaction signing method, Im wondering if I need to copy a set for code to do it because the signing method is shared across the code. Or is there any customize module for implementing it?

[webmaster128]

Could you commit your local changed and create a draft PR with what you have? Maybe that helps understanding what you are doing and how to best collaborate. I worked on Ethereum client tech before but have no clue about Ethermint.

[vincentysc]

Sure~

[vincentysc]

Hi, I just created a draft PR #1107. This is a quick draft from me and probably I will re-write and enhance it with pubkey type instead of coin type. Just let me know if there are any improvement or suggestions. Thank you!

[webmaster128]

Thank you @vincentysc. I looked at your diff last week. That's very helpful. However, I don't think we want to integrate chain-specific functionality at that level. Sign Mode Direct is a Cosmos sign mode with Cosmos pubkeys and not made to add arbitrary secp256k1 signing. I think you can add Ethermint messages and queries in your client code. But if you need Ethereum signing tooling, you better use Ethereum libs for that.

[vincentysc]

Fully understand. I'll give it a try.

Thank you @webmaster128.

[vincentysc]

Thank you @vincentysc. I looked at your diff last week. That's very helpful. However, I don't think we want to integrate chain-specific functionality at that level. Sign Mode Direct is a Cosmos sign mode with Cosmos pubkeys and not made to add arbitrary secp256k1 signing. I think you can add Ethermint messages and queries in your client code. But if you need Ethereum signing tooling, you better use Ethereum libs for that.

Hi @webmaster128. Actually my project is running a in-app relayer(ts-relayer) to relay its own packets only. When it is Cosmos chains, use CosmJS at it is right now; On Ethermint based chain, switch to use another library. However, this would require quite some refactoring to the (ts-relayer) as it is highly dependant of CosmJs.

So, is the previous approach is good enough for this project? Do you have any other suggestions in your mind?

[garrettparris]

bringing this back, having the same issue with cosmjs signing client on an ethermint based chain. IMO, it stops being a chain-specific problem when multiple chains start trying to do this. would support for this to be re-opened so that ethermint developers dont have to maintain their own forks. I know its more of an ethos shift, @webmaster128 thoughts?

[webmaster128]

See #1351