Add new attachmentBackfill capability

service/src/main/java/org/whispersystems/textsecuregcm/grpc/DeviceCapabilityUtil.java

@@ -19,6 +19,7 @@ public class DeviceCapabilityUtil {
       case DEVICE_CAPABILITY_TRANSFER -> DeviceCapability.TRANSFER;
       case DEVICE_CAPABILITY_DELETE_SYNC -> DeviceCapability.DELETE_SYNC;
       case DEVICE_CAPABILITY_STORAGE_SERVICE_RECORD_KEY_ROTATION -> DeviceCapability.STORAGE_SERVICE_RECORD_KEY_ROTATION;
+      case DEVICE_CAPABILITY_ATTACHMENT_BACKFILL -> DeviceCapability.ATTACHMENT_BACKFILL;
       case DEVICE_CAPABILITY_UNSPECIFIED, UNRECOGNIZED -> throw Status.INVALID_ARGUMENT.withDescription("Unrecognized device capability").asRuntimeException();
     };
   }
@@ -29,6 +30,7 @@ public class DeviceCapabilityUtil {
       case TRANSFER -> org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_TRANSFER;
       case DELETE_SYNC -> org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_DELETE_SYNC;
       case STORAGE_SERVICE_RECORD_KEY_ROTATION -> org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_STORAGE_SERVICE_RECORD_KEY_ROTATION;
+      case ATTACHMENT_BACKFILL -> org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_ATTACHMENT_BACKFILL;
     };
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/storage/DeviceCapability.java

@@ -11,11 +11,21 @@ public enum DeviceCapability {
   STORAGE("storage", AccountCapabilityMode.ANY_DEVICE, false, false),
   TRANSFER("transfer", AccountCapabilityMode.PRIMARY_DEVICE, false, false),
   DELETE_SYNC("deleteSync", AccountCapabilityMode.ALL_DEVICES, true, true),
-  STORAGE_SERVICE_RECORD_KEY_ROTATION("ssre2", AccountCapabilityMode.ALL_DEVICES, true, true);
+  STORAGE_SERVICE_RECORD_KEY_ROTATION("ssre2", AccountCapabilityMode.ALL_DEVICES, true, true),
+  ATTACHMENT_BACKFILL("attachmentBackfill", AccountCapabilityMode.PRIMARY_DEVICE, false, true);
 
   public enum AccountCapabilityMode {
+    /**
+     * The account will have the capability iff the primary device has the capability
+     */
     PRIMARY_DEVICE,
+    /**
+     * The account will have the capability iff any device on the account has the capability
+     */
     ANY_DEVICE,
+    /**
+     * The account will have the capability iff all devices on the account have the capability
+     */
     ALL_DEVICES,
   }
 
@@ -24,6 +34,18 @@ public enum DeviceCapability {
   private final boolean preventDowngrade;
   private final boolean includeInProfile;
 
+  /**
+   * Create a DeviceCapability
+   *
+   * @param name                  The name of the device capability that clients will see
+   * @param accountCapabilityMode How to combine the constituent device's capabilities in the account to an overall
+   *                              account capability
+   * @param preventDowngrade      If true, don't let linked devices join that don't have a device capability if the
+   *                              overall account has the capability. Most of the time this should only be used in
+   *                              conjunction with AccountCapabilityMode.ALL_DEVICES
+   * @param includeInProfile      Whether to return this capability on the account's profile. If false, the capability
+   *                              is only visible to the server
+   */
   DeviceCapability(final String name,
       final AccountCapabilityMode accountCapabilityMode,
       final boolean preventDowngrade,

service/src/main/proto/org/signal/chat/common.proto

@@ -100,6 +100,7 @@ enum DeviceCapability {
   DEVICE_CAPABILITY_DELETE_SYNC = 3;
   reserved 4;
   DEVICE_CAPABILITY_STORAGE_SERVICE_RECORD_KEY_ROTATION = 5;
+  DEVICE_CAPABILITY_ATTACHMENT_BACKFILL = 6;
 }
 
 message ZkCredential {

service/src/test/java/org/whispersystems/textsecuregcm/controllers/ProfileControllerTest.java

@@ -442,8 +442,10 @@ class ProfileControllerTest {
 
   @CartesianTest
   void testProfileCapabilities(
-      @CartesianTest.Values(booleans = {true, false}) final boolean isDeleteSyncSupported) {
+      @CartesianTest.Values(booleans = {true, false}) final boolean isDeleteSyncSupported,
+      @CartesianTest.Values(booleans = {true, false}) final boolean isAttachmentBackfillSupported) {
     when(capabilitiesAccount.hasCapability(DeviceCapability.DELETE_SYNC)).thenReturn(isDeleteSyncSupported);
+    when(capabilitiesAccount.hasCapability(DeviceCapability.ATTACHMENT_BACKFILL)).thenReturn(isAttachmentBackfillSupported);
     final BaseProfileResponse profile = resources.getJerseyTest()
         .target("/v1/profile/" + AuthHelper.VALID_UUID)
         .request()
@@ -451,6 +453,7 @@ class ProfileControllerTest {
         .get(BaseProfileResponse.class);
 
     assertEquals(isDeleteSyncSupported, profile.getCapabilities().get("deleteSync"));
+    assertEquals(isAttachmentBackfillSupported, profile.getCapabilities().get("attachmentBackfill"));
   }
 
   @Test

service/src/test/java/org/whispersystems/textsecuregcm/grpc/DevicesGrpcServiceTest.java

@@ -434,7 +434,8 @@ class DevicesGrpcServiceTest extends SimpleBaseGrpcTest<DevicesGrpcService, Devi
       @CartesianTest.Values(bytes = {Device.PRIMARY_ID, Device.PRIMARY_ID + 1}) final byte deviceId,
       @CartesianTest.Values(booleans = {true, false}) final boolean storage,
       @CartesianTest.Values(booleans = {true, false}) final boolean transfer,
-      @CartesianTest.Values(booleans = {true, false}) final boolean deleteSync) {
+      @CartesianTest.Values(booleans = {true, false}) final boolean deleteSync,
+      @CartesianTest.Values(booleans = {true, false}) final boolean attachmentBackfill) {
 
     mockAuthenticationInterceptor().setAuthenticatedDevice(AUTHENTICATED_ACI, deviceId);
 
@@ -455,6 +456,10 @@ class DevicesGrpcServiceTest extends SimpleBaseGrpcTest<DevicesGrpcService, Devi
       requestBuilder.addCapabilities(org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_DELETE_SYNC);
     }
 
+    if (attachmentBackfill) {
+      requestBuilder.addCapabilities(org.signal.chat.common.DeviceCapability.DEVICE_CAPABILITY_ATTACHMENT_BACKFILL);
+    }
+
     final SetCapabilitiesResponse ignored = authenticatedServiceStub().setCapabilities(requestBuilder.build());
 
     final Set<DeviceCapability> expectedCapabilities = new HashSet<>();
@@ -471,6 +476,10 @@ class DevicesGrpcServiceTest extends SimpleBaseGrpcTest<DevicesGrpcService, Devi
       expectedCapabilities.add(DeviceCapability.DELETE_SYNC);
     }
 
+    if (attachmentBackfill) {
+      expectedCapabilities.add(DeviceCapability.ATTACHMENT_BACKFILL);
+    }
+
     verify(device).setCapabilities(expectedCapabilities);
   }
 }