Introduce a DynamoDB-backed remote config store

service/src/main/java/org/whispersystems/textsecuregcm/configuration/DynamoDbTables.java

@@ -50,17 +50,20 @@ public class DynamoDbTables {
   private final TableWithExpiration redeemedReceipts;
   private final Table subscriptions;
   private final Table profiles;
+  private final Table remoteConfig;
 
   @JsonCreator
   public DynamoDbTables(
       @JsonProperty("issuedReceipts") final IssuedReceiptsTableConfiguration issuedReceipts,
       @JsonProperty("redeemedReceipts") final TableWithExpiration redeemedReceipts,
       @JsonProperty("subscriptions") final Table subscriptions,
-      @JsonProperty("profiles") final Table profiles) {
+      @JsonProperty("profiles") final Table profiles,
+      @JsonProperty("remoteConfig") final Table remoteConfig) {
     this.issuedReceipts = issuedReceipts;
     this.redeemedReceipts = redeemedReceipts;
     this.subscriptions = subscriptions;
     this.profiles = profiles;
+    this.remoteConfig = remoteConfig;
   }
 
   @Valid
@@ -86,4 +89,10 @@ public class DynamoDbTables {
   public Table getProfiles() {
     return profiles;
   }
+
+  @Valid
+  @NotNull
+  public Table getRemoteConfig() {
+    return remoteConfig;
+  }
 }

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

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2013-2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.storage;
+
+import java.util.List;
+
+public interface RemoteConfigStore {
+
+  void set(RemoteConfig remoteConfig);
+
+  List<RemoteConfig> getAll();
+
+  void delete(String name);
+}

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

@@ -15,7 +15,7 @@ import java.util.UUID;
 import org.whispersystems.textsecuregcm.storage.mappers.RemoteConfigRowMapper;
 import org.whispersystems.textsecuregcm.util.Constants;
 
-public class RemoteConfigs {
+public class RemoteConfigs implements RemoteConfigStore {
 
   public static final String ID            = "id";
   public static final String NAME          = "name";
@@ -38,6 +38,7 @@ public class RemoteConfigs {
     this.database.getDatabase().registerArrayType(UUID.class, "uuid");
   }
 
+  @Override
   public void set(RemoteConfig remoteConfig) {
     database.use(jdbi -> jdbi.useHandle(handle -> {
       try (Timer.Context ignored = setTimer.time()) {
@@ -53,6 +54,7 @@ public class RemoteConfigs {
     }));
   }
 
+  @Override
   public List<RemoteConfig> getAll() {
     return database.with(jdbi -> jdbi.withHandle(handle -> {
       try (Timer.Context ignored = getAllTimer.time()) {
@@ -63,6 +65,7 @@ public class RemoteConfigs {
     }));
   }
 
+  @Override
   public void delete(String name) {
     database.use(jdbi -> jdbi.useHandle(handle -> {
       try (Timer.Context ignored = deleteTimer.time()) {

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

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2013-2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.storage;
+
+import org.whispersystems.textsecuregcm.util.AttributeValues;
+import org.whispersystems.textsecuregcm.util.UUIDUtil;
+import software.amazon.awssdk.core.SdkBytes;
+import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
+import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
+import software.amazon.awssdk.services.dynamodb.model.DeleteItemRequest;
+import software.amazon.awssdk.services.dynamodb.model.PutItemRequest;
+import software.amazon.awssdk.services.dynamodb.model.ScanRequest;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+public class RemoteConfigsDynamoDb implements RemoteConfigStore {
+
+  private final DynamoDbClient dynamoDbClient;
+  private final String tableName;
+
+  // Config name; string
+  static final String KEY_NAME = "N";
+  // Rollout percentage; integer
+  private static final String ATTR_PERCENTAGE = "P";
+  // Enrolled UUIDs (ACIs); list of byte arrays
+  private static final String ATTR_UUIDS = "U";
+  // Default value; string
+  private static final String ATTR_DEFAULT_VALUE = "D";
+  // Value when enrolled; string
+  private static final String ATTR_VALUE = "V";
+  // Hash key; string
+  private static final String ATTR_HASH_KEY = "H";
+
+  public RemoteConfigsDynamoDb(final DynamoDbClient dynamoDbClient, final String tableName) {
+    this.dynamoDbClient = dynamoDbClient;
+    this.tableName = tableName;
+  }
+
+  @Override
+  public void set(final RemoteConfig remoteConfig) {
+    final Map<String, AttributeValue> item = new HashMap<>(Map.of(
+        KEY_NAME, AttributeValues.fromString(remoteConfig.getName()),
+        ATTR_PERCENTAGE, AttributeValues.fromInt(remoteConfig.getPercentage())));
+
+    if (remoteConfig.getUuids() != null && !remoteConfig.getUuids().isEmpty()) {
+      final List<SdkBytes> uuidByteSets = remoteConfig.getUuids().stream()
+          .map(UUIDUtil::toByteBuffer)
+          .map(SdkBytes::fromByteBuffer)
+          .collect(Collectors.toList());
+
+      item.put(ATTR_UUIDS, AttributeValue.builder().bs(uuidByteSets).build());
+    }
+
+    if (remoteConfig.getDefaultValue() != null) {
+      item.put(ATTR_DEFAULT_VALUE, AttributeValues.fromString(remoteConfig.getDefaultValue()));
+    }
+
+    if (remoteConfig.getValue() != null) {
+      item.put(ATTR_VALUE, AttributeValues.fromString(remoteConfig.getValue()));
+    }
+
+    if (remoteConfig.getHashKey() != null) {
+      item.put(ATTR_HASH_KEY, AttributeValues.fromString(remoteConfig.getHashKey()));
+    }
+
+    dynamoDbClient.putItem(PutItemRequest.builder()
+        .tableName(tableName)
+        .item(item)
+        .build());
+  }
+
+  @Override
+  public List<RemoteConfig> getAll() {
+    return dynamoDbClient.scanPaginator(ScanRequest.builder()
+            .tableName(tableName)
+            .consistentRead(true)
+            .build())
+        .items()
+        .stream()
+        .map(item -> {
+          final String name = AttributeValues.getString(item, KEY_NAME, null);
+          final int percentage = AttributeValues.getInt(item, ATTR_PERCENTAGE, 0);
+          final String defaultValue = AttributeValues.getString(item, ATTR_DEFAULT_VALUE, null);
+          final String value = AttributeValues.getString(item, ATTR_VALUE, null);
+          final String hashKey = AttributeValues.getString(item, ATTR_HASH_KEY, null);
+
+          final Set<UUID> uuids;
+
+          if (item.containsKey(ATTR_UUIDS)) {
+            uuids = item.get(ATTR_UUIDS).bs().stream()
+                .map(sdkBytes -> UUIDUtil.fromByteBuffer(sdkBytes.asByteBuffer()))
+                .collect(Collectors.toSet());
+          } else {
+            uuids = Collections.emptySet();
+          }
+
+          return new RemoteConfig(name, percentage, uuids, defaultValue, value, hashKey);
+        })
+        .collect(Collectors.toList());
+  }
+
+  @Override
+  public void delete(final String name) {
+    dynamoDbClient.deleteItem(DeleteItemRequest.builder()
+        .tableName(tableName)
+        .key(Map.of(KEY_NAME, AttributeValues.fromString(name)))
+        .build());
+  }
+}

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

@@ -12,11 +12,11 @@ import java.util.function.Supplier;
 
 public class RemoteConfigsManager {
 
-  private final RemoteConfigs remoteConfigs;
+  private final RemoteConfigStore remoteConfigs;
 
   private final Supplier<List<RemoteConfig>> remoteConfigSupplier;
 
-  public RemoteConfigsManager(RemoteConfigs remoteConfigs) {
+  public RemoteConfigsManager(RemoteConfigStore remoteConfigs) {
     this.remoteConfigs = remoteConfigs;
 
     remoteConfigSupplier =