Introduce "service identifiers"

service/src/main/java/org/whispersystems/textsecuregcm/entities/AccountIdentifierResponse.java

@@ -4,7 +4,14 @@
  */
 
 package org.whispersystems.textsecuregcm.entities;
-import javax.validation.constraints.NotNull;
-import java.util.UUID;
 
-public record AccountIdentifierResponse(@NotNull UUID uuid) {}
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import javax.validation.constraints.NotNull;
+import org.whispersystems.textsecuregcm.identity.AciServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
+
+public record AccountIdentifierResponse(@NotNull
+                                        @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                        @JsonDeserialize(using = ServiceIdentifierAdapter.AciServiceIdentifierDeserializer.class)
+                                        AciServiceIdentifier uuid) {}

service/src/main/java/org/whispersystems/textsecuregcm/entities/AccountMismatchedDevices.java

@@ -5,22 +5,14 @@
 
 package org.whispersystems.textsecuregcm.entities;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
-import java.util.UUID;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
-public class AccountMismatchedDevices {
-  @JsonProperty
-  public final UUID uuid;
+public record AccountMismatchedDevices(@JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                       @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                                       ServiceIdentifier uuid,
 
-  @JsonProperty
-  public final MismatchedDevices devices;
-
-  public String toString() {
-    return "AccountMismatchedDevices(" + uuid + ", " + devices + ")";
-  }
-
-  public AccountMismatchedDevices(final UUID uuid, final MismatchedDevices devices) {
-    this.uuid = uuid;
-    this.devices = devices;
-  }
+                                       MismatchedDevices devices) {
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/AccountStaleDevices.java

@@ -5,22 +5,14 @@
 
 package org.whispersystems.textsecuregcm.entities;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
-import java.util.UUID;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
-public class AccountStaleDevices {
-  @JsonProperty
-  public final UUID uuid;
+public record AccountStaleDevices(@JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                  @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                                  ServiceIdentifier uuid,
 
-  @JsonProperty
-  public final StaleDevices devices;
-
-  public String toString() {
-    return "AccountStaleDevices(" + uuid + ", " + devices + ")";
-  }
-
-  public AccountStaleDevices(final UUID uuid, final StaleDevices devices) {
-    this.uuid = uuid;
-    this.devices = devices;
-  }
+                                  StaleDevices devices) {
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/BaseProfileResponse.java

@@ -9,11 +9,11 @@ import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import org.signal.libsignal.protocol.IdentityKey;
-import org.signal.libsignal.protocol.ecc.ECPublicKey;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 import org.whispersystems.textsecuregcm.util.IdentityKeyAdapter;
 
 import java.util.List;
-import java.util.UUID;
 
 public class BaseProfileResponse {
 
@@ -35,7 +35,9 @@ public class BaseProfileResponse {
   private List<Badge> badges;
 
   @JsonProperty
-  private UUID uuid;
+  @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+  @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+  private ServiceIdentifier uuid;
 
   public BaseProfileResponse() {
   }
@@ -45,7 +47,7 @@ public class BaseProfileResponse {
       final boolean unrestrictedUnidentifiedAccess,
       final UserCapabilities capabilities,
       final List<Badge> badges,
-      final UUID uuid) {
+      final ServiceIdentifier uuid) {
 
     this.identityKey = identityKey;
     this.unidentifiedAccess = unidentifiedAccess;
@@ -75,7 +77,7 @@ public class BaseProfileResponse {
     return badges;
   }
 
-  public UUID getUuid() {
+  public ServiceIdentifier getUuid() {
     return uuid;
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/BatchIdentityCheckRequest.java

@@ -5,13 +5,15 @@
 
 package org.whispersystems.textsecuregcm.entities;
 
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import java.util.List;
-import java.util.UUID;
-import javax.annotation.Nullable;
 import javax.validation.Valid;
 import javax.validation.constraints.NotNull;
 import javax.validation.constraints.Size;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
 import org.whispersystems.textsecuregcm.util.ExactlySize;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
 public record BatchIdentityCheckRequest(@Valid @NotNull @Size(max = 1000) List<Element> elements) {
 
@@ -20,18 +22,13 @@ public record BatchIdentityCheckRequest(@Valid @NotNull @Size(max = 1000) List<E
    * @param fingerprint most significant 4 bytes of SHA-256 of the 33-byte identity key field (32-byte curve25519 public
    *                    key prefixed with 0x05)
    */
-  public record Element(@Deprecated @Nullable UUID aci,
-                        @Nullable UUID uuid,
-                        @NotNull @ExactlySize(4) byte[] fingerprint) {
+  public record Element(@NotNull
+                        @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                        @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                        ServiceIdentifier uuid,
 
-    public Element {
-      if (aci == null && uuid == null) {
-        throw new IllegalArgumentException("aci and uuid cannot both be null");
-      }
-
-      if (aci != null && uuid != null) {
-        throw new IllegalArgumentException("aci and uuid cannot both be non-null");
-      }
-    }
+                        @NotNull
+                        @ExactlySize(4)
+                        byte[] fingerprint) {
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/BatchIdentityCheckResponse.java

@@ -6,39 +6,27 @@
 package org.whispersystems.textsecuregcm.entities;
 
 import com.fasterxml.jackson.annotation.JsonInclude;
-import java.util.List;
-import java.util.UUID;
-import javax.annotation.Nullable;
-import javax.validation.Valid;
-import javax.validation.constraints.NotNull;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import java.util.List;
+import javax.validation.Valid;
+import javax.validation.constraints.NotNull;
 import org.signal.libsignal.protocol.IdentityKey;
-import org.signal.libsignal.protocol.ecc.ECPublicKey;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
 import org.whispersystems.textsecuregcm.util.IdentityKeyAdapter;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
 public record BatchIdentityCheckResponse(@Valid List<Element> elements) {
 
-  public record Element(@Deprecated
-                        @JsonInclude(JsonInclude.Include.NON_EMPTY)
-                        @Nullable UUID aci,
-
-                        @JsonInclude(JsonInclude.Include.NON_EMPTY)
-                        @Nullable UUID uuid,
+  public record Element(@JsonInclude(JsonInclude.Include.NON_EMPTY)
+                        @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                        @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                        @NotNull
+                        ServiceIdentifier uuid,
 
                         @NotNull
                         @JsonSerialize(using = IdentityKeyAdapter.Serializer.class)
                         @JsonDeserialize(using = IdentityKeyAdapter.Deserializer.class)
                         IdentityKey identityKey) {
-
-    public Element {
-      if (aci == null && uuid == null) {
-        throw new IllegalArgumentException("aci and uuid cannot both be null");
-      }
-
-      if (aci != null && uuid != null) {
-        throw new IllegalArgumentException("aci and uuid cannot both be non-null");
-      }
-    }
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/IncomingMessage.java

@@ -6,14 +6,15 @@ package org.whispersystems.textsecuregcm.entities;
 
 import com.google.protobuf.ByteString;
 import java.util.Base64;
-import java.util.UUID;
 import javax.annotation.Nullable;
 import org.apache.commons.lang3.StringUtils;
+import org.whispersystems.textsecuregcm.identity.AciServiceIdentifier;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
 import org.whispersystems.textsecuregcm.storage.Account;
 
 public record IncomingMessage(int type, long destinationDeviceId, int destinationRegistrationId, String content) {
 
-  public MessageProtos.Envelope toEnvelope(final UUID destinationUuid,
+  public MessageProtos.Envelope toEnvelope(final ServiceIdentifier destinationIdentifier,
       @Nullable Account sourceAccount,
       @Nullable Long sourceDeviceId,
       final long timestamp,
@@ -32,13 +33,13 @@ public record IncomingMessage(int type, long destinationDeviceId, int destinatio
     envelopeBuilder.setType(envelopeType)
         .setTimestamp(timestamp)
         .setServerTimestamp(System.currentTimeMillis())
-        .setDestinationUuid(destinationUuid.toString())
+        .setDestinationUuid(destinationIdentifier.toServiceIdentifierString())
         .setStory(story)
         .setUrgent(urgent);
 
     if (sourceAccount != null && sourceDeviceId != null) {
       envelopeBuilder
-          .setSourceUuid(sourceAccount.getUuid().toString())
+          .setSourceUuid(new AciServiceIdentifier(sourceAccount.getUuid()).toServiceIdentifierString())
           .setSourceDevice(sourceDeviceId.intValue());
     }
 

service/src/main/java/org/whispersystems/textsecuregcm/entities/MismatchedDevices.java

@@ -6,31 +6,15 @@
 package org.whispersystems.textsecuregcm.entities;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
-import com.google.common.annotations.VisibleForTesting;
 import io.swagger.v3.oas.annotations.media.Schema;
 
 import java.util.List;
 
-public class MismatchedDevices {
-
-  @JsonProperty
-  @Schema(description = "Devices present on the account but absent in the request")
-  public List<Long> missingDevices;
-
-  @JsonProperty
-  @Schema(description = "Devices absent on the request but present in the account")
-  public List<Long> extraDevices;
-
-  @VisibleForTesting
-  public MismatchedDevices() {}
-
-  public String toString() {
-    return "MismatchedDevices(" + missingDevices + ", " + extraDevices + ")";
-  }
-
-  public MismatchedDevices(List<Long> missingDevices, List<Long> extraDevices) {
-    this.missingDevices = missingDevices;
-    this.extraDevices   = extraDevices;
-  }
+public record MismatchedDevices(@JsonProperty
+                                @Schema(description = "Devices present on the account but absent in the request")
+                                List<Long> missingDevices,
 
+                                @JsonProperty
+                                @Schema(description = "Devices absent on the request but present in the account")
+                                List<Long> extraDevices) {
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/MultiRecipientMessage.java

@@ -8,7 +8,7 @@ package org.whispersystems.textsecuregcm.entities;
 import static com.codahale.metrics.MetricRegistry.name;
 
 import java.util.Arrays;
-import java.util.UUID;
+import java.util.Objects;
 import javax.validation.Valid;
 import javax.validation.constraints.AssertTrue;
 import javax.validation.constraints.Max;
@@ -16,58 +16,33 @@ import javax.validation.constraints.Min;
 import javax.validation.constraints.NotNull;
 import javax.validation.constraints.Size;
 
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import org.whispersystems.textsecuregcm.controllers.MessageController;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
 import org.whispersystems.textsecuregcm.providers.MultiRecipientMessageProvider;
 import org.whispersystems.textsecuregcm.util.Pair;
 
 import io.micrometer.core.instrument.Counter;
 import io.micrometer.core.instrument.Metrics;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
-public class MultiRecipientMessage {
+public record MultiRecipientMessage(
+    @NotNull @Size(min = 1, max = MultiRecipientMessageProvider.MAX_RECIPIENT_COUNT) @Valid Recipient[] recipients,
+    @NotNull @Size(min = 32) byte[] commonPayload) {
 
   private static final Counter REJECT_DUPLICATE_RECIPIENT_COUNTER =
       Metrics.counter(
           name(MessageController.class, "rejectDuplicateRecipients"),
           "multiRecipient", "false");
 
-  public static class Recipient {
-
-    @NotNull
-    private final UUID uuid;
-
-    @Min(1)
-    private final long deviceId;
-
-    @Min(0)
-    @Max(65535)
-    private final int registrationId;
-
-    @Size(min = 48, max = 48)
-    @NotNull
-    private final byte[] perRecipientKeyMaterial;
-
-    public Recipient(UUID uuid, long deviceId, int registrationId, byte[] perRecipientKeyMaterial) {
-      this.uuid = uuid;
-      this.deviceId = deviceId;
-      this.registrationId = registrationId;
-      this.perRecipientKeyMaterial = perRecipientKeyMaterial;
-    }
-
-    public UUID getUuid() {
-      return uuid;
-    }
-
-    public long getDeviceId() {
-      return deviceId;
-    }
-
-    public int getRegistrationId() {
-      return registrationId;
-    }
-
-    public byte[] getPerRecipientKeyMaterial() {
-      return perRecipientKeyMaterial;
-    }
+  public record Recipient(@NotNull
+                          @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                          @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                          ServiceIdentifier uuid,
+                          @Min(1) long deviceId,
+                          @Min(0) @Max(65535) int registrationId,
+                          @Size(min = 48, max = 48) @NotNull byte[] perRecipientKeyMaterial) {
 
     @Override
     public boolean equals(final Object o) {
@@ -75,60 +50,48 @@ public class MultiRecipientMessage {
         return true;
       if (o == null || getClass() != o.getClass())
         return false;
-
       Recipient recipient = (Recipient) o;
-
-      if (deviceId != recipient.deviceId)
-        return false;
-      if (registrationId != recipient.registrationId)
-        return false;
-      if (!uuid.equals(recipient.uuid))
-        return false;
-      return Arrays.equals(perRecipientKeyMaterial, recipient.perRecipientKeyMaterial);
+      return deviceId == recipient.deviceId && registrationId == recipient.registrationId && uuid.equals(recipient.uuid)
+          && Arrays.equals(perRecipientKeyMaterial, recipient.perRecipientKeyMaterial);
     }
 
     @Override
     public int hashCode() {
-      int result = uuid.hashCode();
-      result = 31 * result + (int) (deviceId ^ (deviceId >>> 32));
-      result = 31 * result + registrationId;
+      int result = Objects.hash(uuid, deviceId, registrationId);
       result = 31 * result + Arrays.hashCode(perRecipientKeyMaterial);
       return result;
     }
-
-    public String toString() {
-      return "Recipient(" + uuid + ", " + deviceId + ", " + registrationId + ", " + Arrays.toString(perRecipientKeyMaterial) + ")";
-    }
   }
 
-  @NotNull
-  @Size(min = 1, max = MultiRecipientMessageProvider.MAX_RECIPIENT_COUNT)
-  @Valid
-  private final Recipient[] recipients;
-
-  @NotNull
-  @Size(min = 32)
-  private final byte[] commonPayload;
-
   public MultiRecipientMessage(Recipient[] recipients, byte[] commonPayload) {
     this.recipients = recipients;
     this.commonPayload = commonPayload;
   }
 
-  public Recipient[] getRecipients() {
-    return recipients;
-  }
-
-  public byte[] getCommonPayload() {
-    return commonPayload;
-  }
-
   @AssertTrue
   public boolean hasNoDuplicateRecipients() {
-    boolean valid = Arrays.stream(recipients).map(r -> new Pair<>(r.getUuid(), r.getDeviceId())).distinct().count() == recipients.length;
+    boolean valid =
+        Arrays.stream(recipients).map(r -> new Pair<>(r.uuid(), r.deviceId())).distinct().count() == recipients.length;
     if (!valid) {
       REJECT_DUPLICATE_RECIPIENT_COUNTER.increment();
     }
     return valid;
   }
+
+  @Override
+  public boolean equals(final Object o) {
+    if (this == o)
+      return true;
+    if (o == null || getClass() != o.getClass())
+      return false;
+    MultiRecipientMessage that = (MultiRecipientMessage) o;
+    return Arrays.equals(recipients, that.recipients) && Arrays.equals(commonPayload, that.commonPayload);
+  }
+
+  @Override
+  public int hashCode() {
+    int result = Arrays.hashCode(recipients);
+    result = 31 * result + Arrays.hashCode(commonPayload);
+    return result;
+  }
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/OutgoingMessageEntity.java

@@ -5,28 +5,50 @@
 
 package org.whispersystems.textsecuregcm.entities;
 
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import com.google.protobuf.ByteString;
 import java.util.Arrays;
 import java.util.Objects;
 import java.util.UUID;
 import javax.annotation.Nullable;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 
-public record OutgoingMessageEntity(UUID guid, int type, long timestamp, @Nullable UUID sourceUuid, int sourceDevice,
-                                    UUID destinationUuid, @Nullable UUID updatedPni, byte[] content,
-                                    long serverTimestamp, boolean urgent, boolean story, @Nullable byte[] reportSpamToken) {
+public record OutgoingMessageEntity(UUID guid,
+                                    int type,
+                                    long timestamp,
+
+                                    @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                    @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                                    @Nullable
+                                    ServiceIdentifier sourceUuid,
+
+                                    int sourceDevice,
+
+                                    @JsonSerialize(using = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                    @JsonDeserialize(using = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                                    ServiceIdentifier destinationUuid,
+
+                                    @Nullable UUID updatedPni,
+                                    byte[] content,
+                                    long serverTimestamp,
+                                    boolean urgent,
+                                    boolean story,
+                                    @Nullable byte[] reportSpamToken) {
 
   public MessageProtos.Envelope toEnvelope() {
     final MessageProtos.Envelope.Builder builder = MessageProtos.Envelope.newBuilder()
         .setType(MessageProtos.Envelope.Type.forNumber(type()))
         .setTimestamp(timestamp())
         .setServerTimestamp(serverTimestamp())
-        .setDestinationUuid(destinationUuid().toString())
+        .setDestinationUuid(destinationUuid().toServiceIdentifierString())
         .setServerGuid(guid().toString())
         .setStory(story)
         .setUrgent(urgent);
 
     if (sourceUuid() != null) {
-      builder.setSourceUuid(sourceUuid().toString());
+      builder.setSourceUuid(sourceUuid().toServiceIdentifierString());
       builder.setSourceDevice(sourceDevice());
     }
 
@@ -51,9 +73,9 @@ public record OutgoingMessageEntity(UUID guid, int type, long timestamp, @Nullab
         UUID.fromString(envelope.getServerGuid()),
         envelope.getType().getNumber(),
         envelope.getTimestamp(),
-        envelope.hasSourceUuid() ? UUID.fromString(envelope.getSourceUuid()) : null,
+        envelope.hasSourceUuid() ? ServiceIdentifier.valueOf(envelope.getSourceUuid()) : null,
         envelope.getSourceDevice(),
-        envelope.hasDestinationUuid() ? UUID.fromString(envelope.getDestinationUuid()) : null,
+        envelope.hasDestinationUuid() ? ServiceIdentifier.valueOf(envelope.getDestinationUuid()) : null,
         envelope.hasUpdatedPni() ? UUID.fromString(envelope.getUpdatedPni()) : null,
         envelope.getContent().toByteArray(),
         envelope.getServerTimestamp(),

service/src/main/java/org/whispersystems/textsecuregcm/entities/SendMultiRecipientMessageResponse.java

@@ -6,27 +6,15 @@
 package org.whispersystems.textsecuregcm.entities;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import com.google.common.annotations.VisibleForTesting;
+import org.whispersystems.textsecuregcm.identity.ServiceIdentifier;
+import org.whispersystems.textsecuregcm.util.ServiceIdentifierAdapter;
 import java.util.List;
 import java.util.UUID;
 
-public class SendMultiRecipientMessageResponse {
-  @JsonProperty
-  private List<UUID> uuids404;
-
-  public SendMultiRecipientMessageResponse() {
-  }
-
-  public String toString() {
-    return "SendMultiRecipientMessageResponse(" + uuids404 + ")";
-  }
-
-  @VisibleForTesting
-  public List<UUID> getUUIDs404() {
-    return this.uuids404;
-  }
-
-  public SendMultiRecipientMessageResponse(final List<UUID> uuids404) {
-    this.uuids404 = uuids404;
-  }
+public record SendMultiRecipientMessageResponse(@JsonSerialize(contentUsing = ServiceIdentifierAdapter.ServiceIdentifierSerializer.class)
+                                                @JsonDeserialize(contentUsing = ServiceIdentifierAdapter.ServiceIdentifierDeserializer.class)
+                                                List<ServiceIdentifier> uuids404) {
 }

service/src/main/java/org/whispersystems/textsecuregcm/entities/StaleDevices.java

@@ -10,20 +10,7 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import java.util.List;
 
-public class StaleDevices {
-
-  @JsonProperty
-  @Schema(description = "Devices that are no longer active")
-  private List<Long> staleDevices;
-
-  public StaleDevices() {}
-
-  public String toString() {
-    return "StaleDevices(" + staleDevices + ")";
-  }
-
-  public StaleDevices(List<Long> staleDevices) {
-    this.staleDevices = staleDevices;
-  }
-
+public record StaleDevices(@JsonProperty
+                           @Schema(description = "Devices that are no longer active")
+                           List<Long> staleDevices) {
 }