Implement validateaddress RPC

[teor2345]

Motivation

Some mining pools use this RPC to check addresses.

Specifications

https://zcash.github.io/rpc/validateaddress.html

Designs

We can call the zcash_address crate to validate shielded and unified addresses. (Zebra also has its own transparent address parsing, but we'd be better to just be consistent and use zcash_address for everything.)

We just need to implement these fields:

Transparent:

• p2pkh
• p2sh
• scriptPubKey (optional, only do it if it's easy)
• pubkey (optional, only do it if it's easy)
• isscript

Related Work

• Implement transparent P2PKH mining address support #5719

[mpguerra]

We should implement these, however since they are not strictly mining RPCs they don't fall within the scope of the MVP.

[teor2345]

We should implement these, however since they are not strictly mining RPCs they don't fall within the scope of the MVP.

Some mining pools won't be able to use Zebra until we implement these RPCs.

[teor2345]

I added validateaddress to this ticket, because some mining pool software needs it. The fields are almost exactly the same as z_validateaddress, just with different names.

[str4d]

Note that the type field is deprecated and will be disabled by default in zcashd 5.4.0. It is being renamed to address_type.

[teor2345]

Note that the type field is deprecated and will be disabled by default in zcashd 5.4.0. It is being renamed to address_type.

Since that change hasn't been released yet, we might use both names until miners update.

[mpguerra]

Hey team! Please add your planning poker estimate with Zenhub @arya2 @conradoplg @dconnolly @oxarbitrage @teor2345 @upbqdn

[mpguerra]

@arya can you please update the estimate here, if necessary, after splitting off the original issue