Off-Chain code with Lucid #plutus #cardano #haskell
Employ Lucid to interact with off-chain code.
Employ blockfrost to connect to Cardano blockchain.
Here we start with Number guess game and the Cardano plutus onChain script is written in Plutarch.
Below is snippet of onCHain code for :
data POurDatum (s :: S) = POurDatum (Term s (PDataRecord '[ "password" ':= PInteger ]))
deriving stock (Generic)
deriving anyclass (PlutusType, PIsData, PDataFields)
instance DerivePlutusType POurDatum where
type DPTStrat _ = PlutusTypeData
instance PTryFrom PData POurDatum
data POurRedeemer (s :: S) = POurRedeemer (Term s (PDataRecord '[ "password" ':= PInteger ]))
deriving stock (Generic)
deriving anyclass (PlutusType, PIsData, PDataFields)
instance DerivePlutusType POurRedeemer where
type DPTStrat _ = PlutusTypeData
instance PTryFrom PData POurRedeemer This is a simple validator where it matches the existing Datum number with Redeemer number, and if its equal then it unlocks the funds. Again this is a trivial example as we inline the Datum so its actually visible but ideally it should be hashed.
pvalidateSmallChecks :: Term s (POurDatum :--> POurRedeemer :--> PScriptContext :--> PUnit)
pvalidateSmallChecks = phoistAcyclic $ plam $ \datum redeemer _ctx -> unTermCont $ do
-- ctxF <- pletFieldsC @'["txInfo"] ctx
-- infoF <- pletFieldsC @'["signatories"] ctxF.txInfo
datumF <- pletFieldsC @'["password"] datum
redeemF <- pletFieldsC @'["password"] redeemer
pure $
pif ( (redeemF.password) #== datumF.password )
(pconstant ())
perror
pvalidateSmallChecksW :: Term s PValidator
pvalidateSmallChecksW = phoistAcyclic $ plam $ \datum redeemer ctx ->
let ourDatum :: Term _ POurDatum
ourDatum = punsafeCoerce datum
ourRedeemer :: Term _ POurRedeemer
ourRedeemer = punsafeCoerce redeemer
in popaque $ pvalidateSmallChecks # ourDatum # ourRedeemer # ctx