Remove generics in Scalar (#2555)

src/kotlin/flwr/src/main/java/dev/flower/android/Serde.kt

@@ -1,13 +1,13 @@
 package dev.flower.android
 
-import java.nio.ByteBuffer
 import com.google.protobuf.ByteString
-import flwr.proto.Transport.ServerMessage
 import flwr.proto.Transport.ClientMessage
-import flwr.proto.Transport.Parameters as ProtoParameters
-import flwr.proto.Transport.Status as ProtoStatus
 import flwr.proto.Transport.Reason
+import flwr.proto.Transport.ServerMessage
+import java.nio.ByteBuffer
+import flwr.proto.Transport.Parameters as ProtoParameters
 import flwr.proto.Transport.Scalar as ProtoScalar
+import flwr.proto.Transport.Status as ProtoStatus
 
 internal fun parametersToProto(parameters: Parameters): ProtoParameters {
     val tensors: MutableList<ByteString> = ArrayList()
@@ -22,11 +22,11 @@ internal fun parametersFromProto(msg: ProtoParameters): Parameters {
 }
 
 internal fun statusToProto(status: Status): ProtoStatus {
-    return ProtoStatus.newBuilder().setCodeValue(status.code).setMessage(status.message).build()
+    return ProtoStatus.newBuilder().setCodeValue(status.code.value).setMessage(status.message).build()
 }
 
 internal fun statusFromProto(msg: ProtoStatus): Status {
-    return Status(msg.codeValue, msg.message)
+    return Status(Code.fromInt(msg.codeValue), msg.message)
 }
 
 internal fun reconnectInsToProto(ins: ReconnectIns): ServerMessage.ReconnectIns {
@@ -47,7 +47,7 @@ internal fun disconnectResToProto(res: DisconnectRes): ClientMessage.DisconnectR
         "WIFI_UNAVAILABLE" -> Reason.WIFI_UNAVAILABLE
         else -> Reason.UNKNOWN
     }
-   return ClientMessage.DisconnectRes.newBuilder().setReason(reason).build()
+    return ClientMessage.DisconnectRes.newBuilder().setReason(reason).build()
 }
 
 internal fun disconnectResFromProto(msg: ClientMessage.DisconnectRes): DisconnectRes {
@@ -173,24 +173,23 @@ internal fun metricsFromProto(proto: Map<String, ProtoScalar>): Metrics {
     return proto.mapValues { (_, value) -> scalarFromProto(value) }
 }
 
-internal inline fun<reified T> scalarToProto(scalar: Scalar<T>): ProtoScalar {
-   return when (T::class) {
-        Scalar.BoolValue::class -> ProtoScalar.newBuilder().setBool(scalar.value as Boolean).build()
-        Scalar.BytesValue::class -> ProtoScalar.newBuilder().setBytes(scalar.value as ByteString).build()
-        Scalar.DoubleValue::class -> ProtoScalar.newBuilder().setDouble(scalar.value as Double).build()
-        Scalar.SInt64Value::class -> ProtoScalar.newBuilder().setSint64(scalar.value as Long).build()
-        Scalar.StringValue::class -> ProtoScalar.newBuilder().setString(scalar.value as String).build()
-        else -> throw IllegalArgumentException("Accepted Types : Bool, Data, Float, Int, Str")
+internal fun scalarToProto(scalar: Scalar): ProtoScalar {
+    return when (scalar) {
+        is Scalar.BoolValue -> ProtoScalar.newBuilder().setBool(scalar.value).build()
+        is Scalar.BytesValue -> ProtoScalar.newBuilder().setBytes(ByteString.copyFrom(scalar.value)).build()
+        is Scalar.SInt64Value -> ProtoScalar.newBuilder().setSint64(scalar.value).build()
+        is Scalar.DoubleValue -> ProtoScalar.newBuilder().setDouble(scalar.value).build()
+        is Scalar.StringValue -> ProtoScalar.newBuilder().setString(scalar.value).build()
     }
 }
 
-internal inline fun <reified T> scalarFromProto(scalarMsg: ProtoScalar): Scalar<T> {
-  return when (scalarMsg.scalarCase) {
-      ProtoScalar.ScalarCase.BOOL -> Scalar.BoolValue(scalarMsg.bool)
-      ProtoScalar.ScalarCase.BYTES -> Scalar.BytesValue(scalarMsg.bytes)
-      ProtoScalar.ScalarCase.DOUBLE -> Scalar.DoubleValue(scalarMsg.double)
-      ProtoScalar.ScalarCase.SINT64 -> Scalar.SInt64Value(scalarMsg.sint64)
-      ProtoScalar.ScalarCase.STRING -> Scalar.StringValue(scalarMsg.string)
-      else -> throw IllegalArgumentException("Accepted Types : Bool, Data, Float, Int, Str")
-   } as Scalar<T>
+internal fun scalarFromProto(scalarMsg: ProtoScalar): Scalar {
+    return when (scalarMsg.scalarCase) {
+        ProtoScalar.ScalarCase.BOOL -> Scalar.BoolValue(scalarMsg.bool)
+        ProtoScalar.ScalarCase.BYTES -> Scalar.BytesValue(ByteBuffer.wrap(scalarMsg.bytes.toByteArray()))
+        ProtoScalar.ScalarCase.DOUBLE -> Scalar.DoubleValue(scalarMsg.double)
+        ProtoScalar.ScalarCase.SINT64 -> Scalar.SInt64Value(scalarMsg.sint64)
+        ProtoScalar.ScalarCase.STRING -> Scalar.StringValue(scalarMsg.string)
+        else -> throw IllegalArgumentException("Accepted Types : Bool, Data, Float, Int, Str")
+    }
 }

src/kotlin/flwr/src/main/java/dev/flower/android/TaskHandler.kt

@@ -38,7 +38,7 @@ internal fun wrapClientMessageInTaskRes(clientMessage: ClientMessage): TaskRes {
     return TaskRes.newBuilder()
         .setTaskId("")
         .setGroupId("")
-        .setWorkloadId("")
+        .setWorkloadId(0)
         .setTask(Task.newBuilder().addAllAncestry(emptyList()).setLegacyClientMessage(clientMessage))
         .build()
 }

src/kotlin/flwr/src/main/java/dev/flower/android/Typing.kt

@@ -1,50 +1,43 @@
 package dev.flower.android
 
-import androidx.annotation.IntDef
-import com.google.protobuf.ByteString
 import java.nio.ByteBuffer
 
 /**
  * Represents a map of metric values.
  */
-typealias Metrics = Map<String, Scalar<Any>>
+typealias Metrics = Map<String, Scalar>
 
 /**
  * Represents a map of configuration values.
  */
-typealias Config = Map<String, Scalar<Any>>
+typealias Config = Map<String, Scalar>
 
 /**
  * Represents a map of properties.
  */
-typealias Properties = Map<String, Scalar<Any>>
+typealias Properties = Map<String, Scalar>
+
 
-@IntDef(
-    Code.OK,
-    Code.GET_PROPERTIES_NOT_IMPLEMENTED,
-    Code.GET_PARAMETERS_NOT_IMPLEMENTED,
-    Code.FIT_NOT_IMPLEMENTED,
-    Code.EVALUATE_NOT_IMPLEMENTED
-)
-@Retention(AnnotationRetention.SOURCE)
-annotation class CodeAnnotation
 
 /**
  * The `Code` class defines client status codes used in the application.
  */
-object Code {
-    // Client status codes.
-    const val OK: Int = 0
-    const val GET_PROPERTIES_NOT_IMPLEMENTED: Int = 1
-    const val GET_PARAMETERS_NOT_IMPLEMENTED: Int = 2
-    const val FIT_NOT_IMPLEMENTED: Int = 3
-    const val EVALUATE_NOT_IMPLEMENTED: Int = 4
+enum class Code(val value: Int) {
+    OK(1),
+    GET_PROPERTIES_NOT_IMPLEMENTED(2),
+    GET_PARAMETERS_NOT_IMPLEMENTED(3),
+    FIT_NOT_IMPLEMENTED(4),
+    EVALUATE_NOT_IMPLEMENTED(5);
+
+    companion object {
+        fun fromInt(value: Int): Code = values().first { it.value == value }
+    }
 }
 
 /**
  * Client status.
  */
-data class Status(val code: Int, val message: String)
+data class Status(val code: Code, val message: String)
 
 /**
  * The `Scalar` class represents a scalar value that can have different data types.
@@ -54,13 +47,12 @@ data class Status(val code: Int, val message: String)
  * some of them arguably do not conform to other definitions of what a scalar is. Source:
  * https://developers.google.com/protocol-buffers/docs/overview#scalar
  */
-sealed class Scalar<T> {
-    abstract val value: T
-    data class BoolValue(override val value: Boolean): Scalar<Boolean>()
-    data class BytesValue(override val value: ByteString): Scalar<ByteString>()
-    data class SInt64Value(override val value: Long): Scalar<Long>()
-    data class DoubleValue(override val value: Double): Scalar<Double>()
-    data class StringValue(override val value: String): Scalar<String>()
+sealed class Scalar {
+    class BoolValue(val value: Boolean) : Scalar()
+    class BytesValue(val value: ByteBuffer) : Scalar()
+    class SInt64Value(val value: Long) : Scalar()
+    class DoubleValue(val value: Double) : Scalar()
+    class StringValue(val value: String) : Scalar()
 }
 
 /**