Develop C++ Support for Harmony Blockchain

[john-harmony]

Overview Support for Harmony Blockchain is to be developed

Background - Reference Material Communication

• via Telegram (Trust Wallet/Harmony)

Key Contact

• Mykola - https://github.com/kolya182

Documents

• https://trustwallet.com/
• https://developer.trustwallet.com/
• Harmony document - https://docs.google.com/document/d/1KJmCNzocnyuA53LcSzbHW5QeLMI6x7mxfSZLgFoQyIQ/edit

Related Tickets

• RPC Compatibility
• API Compatability

Sub Tasks

• [ ] C++ - https://developer.trustwallet.com/wallet-core/newblockchain (YongXia)

Acceptance Criteria

• [ ] Complete Trust Wallet Acceptance Criteria

The above steps are summarized below as a checklist:

• [x] Add the coin definition to coins.json and TWCoinType.
  • [x] Implement functionality in C++. Put it in a subfolder of src/.
  • [x] Address (if necessary).
  • [x] Transaction (if necessary).
• [ ] Signer.
  • [ ] Write unit tests. Put them in a subfolder of tests/.
  • [ ] Mnemonic phrase - > Address derivation test. Put this test in the CoinTests.cpp file.
  • [ ] Transaction signing tests, at least a mainnet transaction test.
  • [ ] Add stake, unstake, get rewards tests if the blockchain is PoS like.
• [x] Add relevant constants in TWEthereumChainID, TWCurve, etc., as necessary.
• [x] Implement address validation and derivation.
• [x] Implement validation and derivation in src/Coin.cpp.
• [x] Add tests for validation in tests/CoinAddressValidationTests.cpp and derivation in tests/CoinAddressDerivationTests.cpp.
• [x] Write interface header in include/TrustWalletCore and implement the interface in src/interface.
  • [ ] Address interface (if necessary).
  • [ ] Signing interface.
• [x] Validate generated code in Android an iOS projects. Write integration tests for each.
• [ ] Upload coin icon to trustwallet/assets if necessary.

[john-harmony]

Also the Protobuf definitons can be found here

[john-harmony]

Key Difference Harmony and Ethereum

1. The prefix of rpc is different, 'hmy' instead of 'eth'
2. Address format, sdk uses two, the default use checksum, it is recommended to use bech32. has been defined in the SDK
3. Transaction uses rlp, but adds two fields, one is shardID and the other is toShardID
4. There are some rpc Ethereum, there is no harmony, we will discuss it in detail during the process.

So for the JS project, you can directly modify the existing Ethereum library, or you can use the SDK package to see your engineering needs. The best practice is to extend the SDK's Transaction class and then add your custom part. The biggest difference is that Harmony does not use eth_sendTransaction and uses eth_sendRawTransaction to send the signed bytes. Of course, this is called hmy_sendRawTransaction Please let the engineer responsible for js communicate with me. The current test network (with RPC) is still in preparation, so please use the local node for development testing. If you need me to be a custom provider, there is no problem.

Ok Is there an open source wallet project? I haven't done it yet.

[john-harmony]

Ethereum C++ Projects

• Ethereum Aleth
• Ravecoin example also in harmony doc above

[john-harmony]

Harmony ProtoBuf definitions

[john-harmony]

Relevant testing testing frameworkis gtest

[john-harmony]

@yzhoujuly work with Charles to get the information you need. You can run sample transactions through the dapp examples - test sign and you'll need to raise a request here for the harmony public coin ID.