Plutus: Pioneers Program 4th cohort - Lecture 8 - Staking

We came over Cardano's staking mechanism over and over.

At some point, a reward transaction is emitted and, like Script and Minting, there are Validators:

mkStakeValidator :: () -> ScriptContext -> Bool
mkStakeValidator () ctx = case scriptContextPurpose ctx of
    Certifying _   -> True
    Rewarding cred -> traceIfFalse "insufficient reward sharing" $ amount cred >= 1
    _              -> False
  where
    info :: TxInfo
    info = scriptContextTxInfo ctx

    amount :: StakingCredential -> Integer
    amount cred = case PlutusTx.lookup cred $ txInfoWdrl info of
        Just amt -> amt
        Nothing  -> traceError "withdrawal not found"

{-# INLINABLE mkWrappedStakeValidator #-}
mkWrappedStakeValidator :: BuiltinData -> BuiltinData -> ()
mkWrappedStakeValidator = wrapStakeValidator mkStakeValidator

stakeValidator :: StakeValidator
stakeValidator = mkStakeValidatorScript $$(PlutusTx.compile [|| mkWrappedStakeValidator ||])

If we have a closer look, all Validators are wrappers around Script:

newtype Validator = Validator Script

mkValidatorScript :: CompiledCode (BuiltinData -> BuiltinData -> BuiltinData -> ()) -> Validator

newtype MintingPolicy = MintingPolicy Script

mkMintingPolicyScript :: CompiledCode (BuiltinData -> BuiltinData -> ()) -> MintingPolicy

newtype StakeValidator = StakeValidator Script

mkStakeValidatorScript :: CompiledCode (BuiltinData -> BuiltinData -> BuiltinData -> ()) -> StakeValidator

It takes the following steps to be activated:

• Build a stake address from the script (cardano-cli stake-address build)
• Build the payment address (cardano-cli stake-address build)
• Build stake registration and delegation certificates (cardano-cli stake-address delegation-certificate and cardano-cli stake-address registration-certificate)
• Build, sign, and submit the registration transaction with certificates and the stake script (cardano-cli transaction build|sign|submit --certificate-*)
• Build, sign, and submit the withdrawal transaction with the stake script (cardano-cli transaction build|sign|submit --withdrawal-*)