urbit/WALLET.scratch.md

btc-wallet-* Scratch Code

xpub

Mnemonic

absurd sick rose mask magnet know slide spell rent casual someone grant giant inhale toward

=xpub1 'zpub6r8dKyWJ31XF6n69KKeEwLjVC5ruqAbiJ4QCqLsrV36Mvx9WEjUaiPNPGFLHNCCqgCdy6iZC8ZgHsm6a1AUTVBMVbKGemNcWFcwBGSjJKbD'
=xpub2 'xpub6D7yaZieZEeG617UcKXDhbsDeso6bmxSAiGWkvkASoiwcjaRtrH5HeNRnDT25s7zmxYzj6MtFe32dVqcf9YcBKKgn9THHjwn2uSjkvobK4e'
=bl -build-file %/lib/btc-wallet-store/hoon

add

:btc-wallet-store|action [%add-wallet xpub ~ ~]

get address at indices

=walt1 (from-xpub:walt:bl xpub1 ~ ~)
(get-address:walt1 %0 0)

update address data

=walt1 (from-xpub:walt:bl xpub1 ~ ~)
(~(mk-address walt1 %0) 0)
::  gives bc1q0adfj7ur750hjwufzzlfj5ytqzsnd7fz9fjuzc
=walt1 (~(insert-address walt1 %0) [%bech32 'bc1q0adfj7ur750hjwufzzlfj5ytqzsnd7fz9fjuzc'] [%0 0 ~])
nixt.st.walt1
::  gives [p=1 q=0] (nixt updated since it was 0)
=walt1 (~(insert-address walt1 %0) [%bech32 'bc1qa5jcdww8u8493zttjjf6q5wu89e6knpvmsh7x4'] [%0 2 ~])
nixt.st.walt1
::  gives [p=1 q=0] (no update)
=walt1 (~(insert-address walt1 %0) [%bech32 'bc1qvqrdh8suyv63ntaa0d7hmcamavv8283sngh6e5'] [%0 1 ~])
nixt.st.walt1
::  gives [p=3 q=0]  (skips index 2, since already a used address there)

=walt1 (insert-address:walt1 [%bech32 'bc1qvqrdh8suyv63ntaa0d7hmcamavv8283sngh6e5'] [%0 4 ~])
::  gives error, because address is inserted at the wrong index

generate new address (for receiving payment)

=walt1 (from-xpub:walt:bl xpub1 ~ ~)
=res ~(gen-address walt1 %0)
p.res
nixt.st.q.res
::  gives 
::  [%bech32 'bc1q0adfj7ur750hjwufzzlfj5ytqzsnd7fz9fjuzc']
::  [p=1 q=0]

Scanning

Mnemonic

abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about

manual scanning of empty wallet

With max-gap=3

:btc-wallet-hook|action [%set-provider ~dopzod]
=btc -build-file %/lib/btc/hoon
=scan-xpub 'zpub6rFR7y4Q2AijBEqTUquhVz398htDFrtymD9xYYfG1m4wAcvPhXNfE3EfH1r1ADqtfSdVCToUG868RvUUkgDKf31mGDtKsAYz2oz2AGutZYs'
:btc-wallet-store|action [%add-wallet scan-xpub ~ [~ 3]]
:btc-wallet-store +dbug
:: shows scans with the xpub and {0 1 2} todos

::  %0 account has no used
:btc-wallet-store|action [%watch-address scan-xpub %0 1 *(set utxo:btc) used=%.n]
:btc-wallet-store|action [%watch-address scan-xpub %0 2 *(set utxo:btc) used=%.n]
:btc-wallet-store|action [%watch-address scan-xpub %0 0 *(set utxo:btc) used=%.n]
::  dbug should give empty for scans: [xpub %0]
:btc-wallet-store|action [%watch-address scan-xpub %1 2 *(set utxo:btc) used=%.n]
:btc-wallet-store|action [%watch-address scan-xpub %1 0 *(set utxo:btc) used=%.n]
:btc-wallet-store|action [%watch-address scan-xpub %1 1 *(set utxo:btc) used=%.y]
:: dbug should show re-filled scans: [xpub %1]

Algos

Scan addresses

in wallet-store

• maps:

  • scans ([xpub chyg] -> waltscan)

• start scan

  • params: xpub
  • get nixt from wallet
  • choose the next N indices WITHOUT generating
  • store their indexes in batch
  • new entry in scans for this xpub+both chyg
  • send address+ idx [xpub chyg] to wallet-hook for processing

• on :watch-address action

  • watch-address in the wallet IF used
  • delete idx from todo.batch
  • if the todos in this xpub+chyg batch are empty, check whether wallet is scanned

in wallet-hook

• types

  • req-id=@ux: hash160 of (cat xpub chyg)
  • pend/fail: (req-id -> [=idx key=[xpub chyg]])
  • timeouts: (req-id -> @da) -- store Behns for each req

• send address-watch req

  • send address to provider with req-id
  • set a Behn for 30s, put in timeouts

• on response from server

  • insert the address into the wallet

• on error

• on timeout

Monitor addresses

• nixt also stores next 50 addresses for each account.
• every update-address call also checks those

subscribe to provider

• btc: FIX and think out hook->provider data/sub flow
  • on sub: add provider, connected is false
  • negative ack: delete provider
  • positive ack: check whether it's our current provider, then set connected to true. Retry items in pend/fail
• btc: if no provider set, keep items in pend/fail

make a payment

• make payment
  • get address
  • on-agent gets return value, construct tx
  • store tx (view or other command can get it)

:: ++ send-address-update |= [xpub=tape =walt a=address:btc us=(set utxo)] ^- (quip card state) : state(walts (~(put by walts.state) xpub walt)) ~%give %fact ~[/wallets] %btc-wallet-store-update !>([%address a us]) ::