Use EpochSecondSerializer for UserRemoteConfigList.serverEpochTime

service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java

@@ -822,7 +822,8 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
             config.getRemoteConfigConfiguration().requiredHostedDomain(),
             config.getRemoteConfigConfiguration().audiences(),
             new GoogleIdTokenVerifier.Builder(new ApacheHttpTransport(), new GsonFactory()),
-            config.getRemoteConfigConfiguration().globalConfig()),
+            config.getRemoteConfigConfiguration().globalConfig(),
+            clock),
         new SecureStorageController(storageCredentialsGenerator),
         new SecureValueRecovery2Controller(svr2CredentialsGenerator, accountsManager),
         new StickerController(rateLimiters, config.getCdnConfiguration().accessKey().value(),

service/src/main/java/org/whispersystems/textsecuregcm/controllers/RemoteConfigController.java

@@ -61,11 +61,14 @@ public class RemoteConfigController {
 
   private final GoogleIdTokenVerifier googleIdTokenVerifier;
 
+  private final Clock clock;
+
   private static final String GLOBAL_CONFIG_PREFIX = "global.";
 
   public RemoteConfigController(RemoteConfigsManager remoteConfigsManager, AdminEventLogger adminEventLogger,
       Set<String> configAuthUsers, String requiredHostedDomain, List<String> audience,
-      final GoogleIdTokenVerifier.Builder googleIdTokenVerifierBuilder, Map<String, String> globalConfig) {
+      final GoogleIdTokenVerifier.Builder googleIdTokenVerifierBuilder, Map<String, String> globalConfig,
+      final Clock clock) {
     this.remoteConfigsManager = remoteConfigsManager;
     this.adminEventLogger = Objects.requireNonNull(adminEventLogger);
     this.configAuthUsers = configAuthUsers;
@@ -73,6 +76,8 @@ public class RemoteConfigController {
 
     this.requiredHostedDomain = requiredHostedDomain;
     this.googleIdTokenVerifier = googleIdTokenVerifierBuilder.setAudience(audience).build();
+
+    this.clock = clock;
   }
 
   @GET
@@ -90,7 +95,7 @@ public class RemoteConfigController {
             config.getUuids());
         return new UserRemoteConfig(config.getName(), inBucket,
             inBucket ? config.getValue() : config.getDefaultValue());
-      }), globalConfigStream).collect(Collectors.toList()), Clock.systemUTC().instant());
+      }), globalConfigStream).collect(Collectors.toList()), clock.instant());
     } catch (NoSuchAlgorithmException e) {
       throw new AssertionError(e);
     }

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

@@ -7,10 +7,10 @@ package org.whispersystems.textsecuregcm.entities;
 
 import com.fasterxml.jackson.annotation.JsonFormat;
 import com.fasterxml.jackson.annotation.JsonProperty;
-
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import java.time.Instant;
-import java.time.temporal.ChronoUnit;
 import java.util.List;
+import org.whispersystems.textsecuregcm.util.InstantAdapter;
 
 public class UserRemoteConfigList {
 
@@ -18,6 +18,7 @@ public class UserRemoteConfigList {
   private List<UserRemoteConfig> config;
 
   @JsonProperty
+  @JsonSerialize(using = InstantAdapter.EpochSecondSerializer.class)
   @JsonFormat(shape = JsonFormat.Shape.NUMBER_INT)
   private Instant serverEpochTime;
 
@@ -25,7 +26,7 @@ public class UserRemoteConfigList {
 
   public UserRemoteConfigList(List<UserRemoteConfig> config, Instant serverEpochTime) {
     this.config = config;
-    this.serverEpochTime = serverEpochTime != null ? serverEpochTime.truncatedTo(ChronoUnit.SECONDS) : null;
+    this.serverEpochTime = serverEpochTime;
   }
 
   public List<UserRemoteConfig> getConfig() {

service/src/main/java/org/whispersystems/textsecuregcm/util/InstantAdapter.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2023 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.util;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import java.io.IOException;
+import java.time.Instant;
+
+public class InstantAdapter {
+
+  public static class EpochSecondSerializer extends JsonSerializer<Instant> {
+
+    @Override
+    public void serialize(final Instant value, final JsonGenerator gen, final SerializerProvider serializers)
+        throws IOException {
+
+      gen.writeNumber(value.getEpochSecond());
+    }
+  }
+
+}