CORDA-2871: Add a callback to ServicesForResolution to allow the Node to modify a LedgerTransaction object.

core/src/main/kotlin/net/corda/core/node/ServiceHub.kt

@@ -10,6 +10,7 @@ import net.corda.core.flows.ContractUpgradeFlow
 import net.corda.core.node.services.*
 import net.corda.core.serialization.SerializeAsToken
 import net.corda.core.transactions.FilteredTransaction
+import net.corda.core.transactions.LedgerTransaction
 import net.corda.core.transactions.SignedTransaction
 import net.corda.core.transactions.TransactionBuilder
 import java.security.PublicKey
@@ -71,6 +72,12 @@ interface ServicesForResolution {
      */
     @Throws(TransactionResolutionException::class, AttachmentResolutionException::class)
     fun loadContractAttachment(stateRef: StateRef): Attachment
+
+    /**
+     * Provides a callback for the Node to customise the [LedgerTransaction].
+     */
+    @JvmDefault
+    fun specialise(ltx: LedgerTransaction): LedgerTransaction = ltx
 }
 
 /**

core/src/main/kotlin/net/corda/core/transactions/TransactionBuilder.kt

@@ -70,8 +70,8 @@ open class TransactionBuilder(
         private fun defaultLockId() = (Strand.currentStrand() as? FlowStateMachine<*>)?.id?.uuid ?: UUID.randomUUID()
         private val log = contextLogger()
 
-        private val ID_PATTERN = "\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*"
+        private const val ID_PATTERN = "\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*"
-        private val FQCP = Pattern.compile("$ID_PATTERN(/$ID_PATTERN)+")
+        private val FQCP: Pattern = Pattern.compile("$ID_PATTERN(/$ID_PATTERN)+")
         private fun isValidJavaClass(identifier: String) = FQCP.matcher(identifier).matches()
     }
 

core/src/main/kotlin/net/corda/core/transactions/WireTransaction.kt

@@ -99,7 +99,8 @@ class WireTransaction(componentGroups: List<ComponentGroup>, val privacySalt: Pr
     @Throws(AttachmentResolutionException::class, TransactionResolutionException::class)
     @DeleteForDJVM
     fun toLedgerTransaction(services: ServicesForResolution): LedgerTransaction {
-        return toLedgerTransactionInternal(
+        return services.specialise(
+            toLedgerTransactionInternal(
                 resolveIdentity = { services.identityService.partyFromKey(it) },
                 resolveAttachment = { services.attachments.openAttachment(it) },
                 resolveStateRefAsSerialized = { resolveStateRefBinaryComponent(it, services) },
@@ -110,6 +111,7 @@ class WireTransaction(componentGroups: List<ComponentGroup>, val privacySalt: Pr
                 // `as?` is used due to [MockServices] not implementing [ServiceHubCoreInternal]
                 isAttachmentTrusted = { (services as? ServiceHubCoreInternal)?.attachmentTrustCalculator?.calculate(it) ?: true }
             )
+        )
     }
 
     // Helper for deprecated toLedgerTransaction
@@ -129,7 +131,7 @@ class WireTransaction(componentGroups: List<ComponentGroup>, val privacySalt: Pr
      * @throws AttachmentResolutionException if a required attachment was not found using [resolveAttachment].
      * @throws TransactionResolutionException if an input was not found not using [resolveStateRef].
      */
-    @Deprecated("Use toLedgerTransaction(ServicesForTransaction) instead")
+    @Deprecated("Use toLedgerTransaction(ServicesForResolution) instead")
     @Throws(AttachmentResolutionException::class, TransactionResolutionException::class)
     fun toLedgerTransaction(
             resolveIdentity: (PublicKey) -> Party?,

node/src/main/kotlin/net/corda/node/internal/ServicesForResolutionImpl.kt

@@ -10,6 +10,7 @@ import net.corda.core.node.services.IdentityService
 import net.corda.core.node.services.NetworkParametersService
 import net.corda.core.node.services.TransactionStorage
 import net.corda.core.transactions.ContractUpgradeWireTransaction
+import net.corda.core.transactions.LedgerTransaction
 import net.corda.core.transactions.NotaryChangeWireTransaction
 import net.corda.core.transactions.WireTransaction
 import net.corda.core.transactions.WireTransaction.Companion.resolveStateRefBinaryComponent
@@ -35,7 +36,7 @@ data class ServicesForResolutionImpl(
         return stateRefs.groupBy { it.txhash }.flatMap {
             val stx = validatedTransactions.getTransaction(it.key) ?: throw TransactionResolutionException(it.key)
             val baseTx = stx.resolveBaseTransaction(this)
-            it.value.map { StateAndRef(baseTx.outputs[it.index], it) }
+            it.value.map { ref -> StateAndRef(baseTx.outputs[ref.index], ref) }
         }.toSet()
     }
 
@@ -69,4 +70,10 @@ data class ServicesForResolutionImpl(
         }
         return inner(stateRef, null)
     }
+
+    override fun specialise(ltx: LedgerTransaction): LedgerTransaction {
+        // Specialise the LedgerTransaction here so that
+        // contracts are verified inside the DJVM!
+        return ltx
+    }
 }