kvutils: Make migration to the new key and value types easier. (#8483)

* kvutils: Make migration to the new key and value types easier.

CHANGELOG_BEGIN
CHANGELOG_END

* kvutils: Extract out common implicit conversions into a trait.

ledger/ledger-on-sql/src/main/scala/com/daml/ledger/on/sql/queries/Queries.scala

@@ -65,10 +65,10 @@ object Queries {
     }
 
   implicit val columnToRawKey: Column[Raw.Key] =
-    columnToByteString.map(Raw.Key)
+    columnToByteString.map(Raw.Key.apply)
 
   implicit val columnToRawValue: Column[Raw.Value] =
-    columnToByteString.map(Raw.Value)
+    columnToByteString.map(Raw.Value.apply)
 
   def rawKey(columnName: String): RowParser[Raw.Key] =
     SqlParser.get(columnName)(columnToRawKey)

ledger/participant-state/kvutils/src/main/scala/com/daml/ledger/participant/state/kvutils/Raw.scala

@@ -5,20 +5,62 @@ package com.daml.ledger.participant.state.kvutils
 
 import com.google.protobuf.ByteString
 
+import scala.language.implicitConversions
+
 object Raw {
 
-  sealed trait Bytes {
+  trait Bytes {
     def bytes: ByteString
 
     final def size: Long = bytes.size.toLong
   }
 
+  object Bytes {
+
+    /** This implicit conversion exists to aid in migration.
+      * It will be deprecated and subsequently removed in the future.
+      */
+    implicit def `ByteString to Raw.Bytes`(bytes: ByteString): Bytes = Unknown(bytes)
+
+    /** This implicit conversion exists to aid in migration.
+      * It will be deprecated and subsequently removed in the future.
+      */
+    implicit def `Raw.Bytes to ByteString`(raw: Bytes): ByteString = raw.bytes
+  }
+
+  trait Companion[Self] {
+
+    def apply(bytes: ByteString): Self
+
+    /** This implicit conversion exists to aid in migration.
+      * It will be deprecated and subsequently removed in the future.
+      */
+    implicit def `ByteString to Self`(bytes: ByteString): Self = apply(bytes)
+
+    /** This implicit conversion exists to aid in migration.
+      * It will be deprecated and subsequently removed in the future.
+      */
+    implicit def `Raw.Bytes to Self`(rawBytes: Bytes): Self = apply(rawBytes.bytes)
+
+  }
+
+  /** This case class only exists to preserve some functionality of
+    * [[com.daml.ledger.participant.state.kvutils.Bytes]].
+    *
+    * It will be removed in the future.
+    */
+  private final case class Unknown(override val bytes: ByteString) extends Bytes
+
   final case class Key(override val bytes: ByteString) extends Bytes
 
+  object Key extends Companion[Key] {
+    implicit val `Key Ordering`: Ordering[Key] = Ordering.by(_.bytes.asReadOnlyByteBuffer)
+  }
+
   final case class Value(override val bytes: ByteString) extends Bytes
 
+  object Value extends Companion[Value]
+
   type KeyValuePair = (Key, Value)
 
-  implicit val `Key Ordering`: Ordering[Key] = Ordering.by(_.bytes.asReadOnlyByteBuffer)
-
 }

ledger/participant-state/kvutils/src/main/scala/com/daml/ledger/participant/state/kvutils/package.scala

@@ -28,6 +28,11 @@ import com.daml.metrics.MetricName
   */
 package object kvutils {
 
+  /** Alias for [[Raw.Bytes]] to aid in migration.
+    * It will be deprecated and subsequently removed in the future.
+    */
+  type Bytes = Raw.Bytes
+
   type DamlStateMap = Map[DamlStateKey, Option[DamlStateValue]]
 
   type CorrelationId = String

ledger/participant-state/kvutils/src/main/scala/com/daml/ledger/validator/LedgerStateAccess.scala

@@ -74,6 +74,20 @@ trait LedgerStateOperations[+LogResult] {
   )(implicit executionContext: ExecutionContext): Future[LogResult]
 }
 
+object LedgerStateOperations {
+
+  /** Alias for [[Raw.Key]] to aid in migration.
+    * It will be deprecated and subsequently removed in the future.
+    */
+  type Key = Raw.Key
+
+  /** Alias for [[Raw.Value]] to aid in migration.
+    * It will be deprecated and subsequently removed in the future.
+    */
+  type Value = Raw.Value
+
+}
+
 /** Convenience class for implementing read and write operations on a backing store that supports batched operations.
   */
 abstract class BatchingLedgerStateOperations[LogResult] extends LedgerStateOperations[LogResult] {