TBD: Define toLedgerTx and fromLedgerTx using ShelleyTx

The cardano-api Tx type is just a wrapper around the ledger and we
should be using that data constructor to do this "conversion".

This also drops a test for "self-healing" auxiliary data hashes, but we
did not require that in the first place: if you modify a transaction
using the ledger-api, make sure to re-compute the auxDataHashTxBodyL.

hydra-cardano-api/src/Hydra/Cardano/Api/Tx.hs

@@ -2,13 +2,6 @@ module Hydra.Cardano.Api.Tx where
 
 import Hydra.Cardano.Api.Prelude
 
-import Hydra.Cardano.Api.KeyWitness (
-  fromLedgerTxWitness,
-  toLedgerBootstrapWitness,
-  toLedgerKeyWitness,
- )
-import Hydra.Cardano.Api.TxScriptValidity (toLedgerScriptValidity)
-
 import Cardano.Api.UTxO qualified as UTxO
 import Cardano.Ledger.Allegra.Scripts (translateTimelock)
 import Cardano.Ledger.Alonzo qualified as Ledger
@@ -31,8 +24,6 @@ import Cardano.Ledger.Api (
   dataTxOutL,
   datsTxWitsL,
   feeTxBodyL,
-  hashScriptTxWitsL,
-  hashTxAuxData,
   inputsTxBodyL,
   isValidTxL,
   mintTxBodyL,
@@ -55,9 +46,8 @@ import Cardano.Ledger.Api (
  )
 import Cardano.Ledger.Api qualified as Ledger
 import Cardano.Ledger.Babbage qualified as Ledger
-import Cardano.Ledger.Babbage.Tx qualified as Ledger
 import Cardano.Ledger.Babbage.TxWits (upgradeTxDats)
-import Cardano.Ledger.BaseTypes (StrictMaybe (..), maybeToStrictMaybe, strictMaybeToMaybe)
+import Cardano.Ledger.BaseTypes (maybeToStrictMaybe)
 import Cardano.Ledger.Coin (Coin (..))
 import Cardano.Ledger.Conway.Scripts (PlutusScript (..))
 import Cardano.Ledger.Conway.Scripts qualified as Conway
@@ -207,55 +197,14 @@ txFee' (getTxBody -> TxBody body) =
 
 -- | Convert a cardano-api 'Tx' into a matching cardano-ledger 'Tx'.
 toLedgerTx ::
-  forall era.
-  ( Ledger.EraCrypto (ShelleyLedgerEra era) ~ StandardCrypto
-  , Ledger.AlonzoEraTx (ShelleyLedgerEra era)
-  ) =>
   Tx era ->
   Ledger.Tx (ShelleyLedgerEra era)
-toLedgerTx = \case
-  Tx (ShelleyTxBody _era body scripts scriptsData auxData validity) vkWits ->
-    let (datums, redeemers) =
-          case scriptsData of
-            TxBodyScriptData _ ds rs -> (ds, rs)
-            TxBodyNoScriptData -> (mempty, Ledger.Redeemers mempty)
-        wits =
-          mkBasicTxWits
-            & addrTxWitsL .~ toLedgerKeyWitness vkWits
-            & bootAddrTxWitsL .~ toLedgerBootstrapWitness vkWits
-            & hashScriptTxWitsL .~ scripts
-            & datsTxWitsL .~ datums
-            & rdmrsTxWitsL .~ redeemers
-     in mkBasicTx
-          (body & auxDataHashTxBodyL .~ maybe SNothing (SJust . hashTxAuxData) auxData)
-          & isValidTxL .~ toLedgerScriptValidity validity
-          & auxDataTxL .~ maybeToStrictMaybe auxData
-          & witsTxL .~ wits
+toLedgerTx (ShelleyTx _era tx) = tx
 
 -- | Convert a cardano-ledger's 'Tx' in the Babbage era into a cardano-api 'Tx'.
-fromLedgerTx :: Ledger.Tx (ShelleyLedgerEra Era) -> Tx Era
-fromLedgerTx ledgerTx =
-  Tx
-    (ShelleyTxBody shelleyBasedEra body' scripts scriptsData (strictMaybeToMaybe auxData) validity)
-    (fromLedgerTxWitness wits)
- where
-  -- XXX: The suggested way (by the ledger team) forward is to use lenses to
-  -- introspect ledger transactions.
-  Ledger.AlonzoTx body wits isValid auxData = ledgerTx
-  body' = body & auxDataHashTxBodyL .~ (hashTxAuxData <$> auxData)
-
-  scripts =
-    Map.elems $ Ledger.txscripts' wits
-
-  scriptsData :: TxBodyScriptData Era
-  scriptsData =
-    TxBodyScriptData
-      alonzoEraOnwards
-      (Ledger.txdats' wits)
-      (Ledger.txrdmrs' wits)
-
-  validity = case isValid of
-    Ledger.IsValid True ->
-      TxScriptValidity alonzoEraOnwards ScriptValid
-    Ledger.IsValid False ->
-      TxScriptValidity alonzoEraOnwards ScriptInvalid
+fromLedgerTx ::
+  IsShelleyBasedEra era =>
+  Ledger.Tx (ShelleyLedgerEra era) ->
+  Tx era
+fromLedgerTx =
+  ShelleyTx shelleyBasedEra

hydra-node/test/Hydra/Ledger/CardanoSpec.hs

@@ -8,11 +8,9 @@ import Hydra.Prelude
 import Test.Hydra.Prelude
 
 import Cardano.Binary (decodeFull, serialize')
-import Cardano.Ledger.Api (auxDataHashTxBodyL, bodyTxL, ensureMinCoinTxOut)
-import Cardano.Ledger.BaseTypes (StrictMaybe (..))
+import Cardano.Ledger.Api (ensureMinCoinTxOut)
 import Cardano.Ledger.Core (PParams ())
 import Cardano.Ledger.Credential (Credential (..))
-import Control.Lens ((.~))
 import Data.Aeson (eitherDecode, encode)
 import Data.Aeson qualified as Aeson
 import Data.Aeson.Lens (key)
@@ -73,8 +71,6 @@ spec =
 
       prop "Roundtrip to and from Ledger" roundtripLedger
 
-      prop "Roundtrip tx metadata" roundtripTxMetadata
-
       prop "Roundtrip CBOR encoding" $ roundtripCBOR @Tx
 
       prop "JSON encoding of Tx according to schema" $
@@ -156,10 +152,6 @@ roundtripLedger :: Tx -> Property
 roundtripLedger tx =
   fromLedgerTx (toLedgerTx tx) === tx
 
-roundtripTxMetadata :: Tx -> Property
-roundtripTxMetadata tx =
-  fromLedgerTx (toLedgerTx tx & bodyTxL . auxDataHashTxBodyL .~ SNothing) === tx
-
 roundtripCBOR :: (Eq a, Show a, ToCBOR a, FromCBOR a) => a -> Property
 roundtripCBOR a =
   let encoded = serialize' a