Provider

::: {.module} Cardano.Node.Client.Provider :::

Protocol-agnostic interface for querying the Cardano blockchain.

data Provider m = Provider
    { queryUTxOs         :: Addr -> m [(TxIn, TxOut ConwayEra)]
    , queryProtocolParams :: m (PParams ConwayEra)
    , evaluateTx         :: Tx ConwayEra -> m (EvaluateTxResult ConwayEra)
    }

Fields

Field	Description
queryUTxOs	Look up UTxOs at an address
queryProtocolParams	Fetch current protocol parameters
evaluateTx	Evaluate script execution units for a transaction

evaluateTx

Evaluates Plutus script execution units for a fully-built transaction. The implementation resolves all transaction inputs (spending, collateral, and reference) from the node, fetches protocol parameters, system start, and the hard-fork interpreter, then calls the ledger's evalTxExUnits locally.

Returns a Map from each script purpose to either a TransactionScriptFailure or the computed ExUnits.

Constructors

Function	Module	Transport
mkN2CProvider	Cardano.Node.Client.N2C.Provider	Unix socket (N2C)

Usage

import Cardano.Node.Client.N2C.Provider (mkN2CProvider)

let provider = mkN2CProvider lsqChannel

utxos  <- queryUTxOs provider myAddress
pp     <- queryProtocolParams provider
exUnits <- evaluateTx provider mySignedTx