eth_defaultAccount

[gavofyork]

Summary

At present two RPCs allow dapps clients to ascertain a default account from which to send transactions: eth_coinbase and eth_accounts. Neither are well-suited. eth_coinbase is the already defined as the preferred block author for mining/sealing and in certain setups this may collide with the account from which transactions should be signed by default.
eth_accounts returns a list of available accounts with not a single one being necessarily favourite.

This proposal is to create a new RPC for the sole duty of determining a default transaction signing account.

Spec

• defaultAccount() -> address: Returns the account that the node owner would prefer to see used. This can be contextual if the node supports multiple calling contexts. Should generally be a member of the set of accounts returned by eth_accounts().

Notes

To be as backwards compatible as possible, client authors should consider:

• implementing eth_coinbase to return the same value as defaultAccount while not mining/sealing;
• implementing eth_accounts to always have the first value of the list returned equivalent to eth_defaultAccount.

Incubation

We propose the final RPC endpoint for this be eth_defaultAccount; if an incubation period is required, we suggest arb_defaultAccount be adopted initially.