如何支持多个 RealmMigrations

Question

我们有多个 android 库，它们彼此独立并依赖于核心库。核心库有CoreRealmManager，负责所有领域操作。

 app
  | --- lib-module-a
  |       \-- lib-module-c
  |       \-- lib-core
  |
  | -x- lib-module-b
  |       \-- lib-core
  |
  | --- lib-module-c
  |       \-- lib-core
  |
  | --- lib-module-d
  |       \-- lib-core
  |
  | --- lib-core

这些库可以有选择地添加到应用程序中，并且应用程序也可以有 RealmClasses。初始化时每个库在调用领域之前调用 CoreRealmManager.addModule(Object additionalModule)。

如果多个库和应用程序想要迁移，则在给定时间点。如何实现？ Realm 仅支持 Single RealmMigration。

@NonNull
static RealmConfiguration.Builder getConfigBundle() {
    RealmConfiguration.Builder builder = new RealmConfiguration.Builder();
    builder.schemaVersion(DB_VERSION)
            .modules(Realm.getDefaultModule(),
                    // Add additional library modules
                    getAdditionalModules());

    if (BuildConfig.DEBUG) {
        builder.deleteRealmIfMigrationNeeded();
    } else {
        // Set migration manager
        builder.migration(new MigrationManager()); // <-- Support multiple migration manager?

        byte[] secretKey = getSecretKey();
        if (secretKey != null) {
            builder.encryptionKey(secretKey);
        }
    }
    return builder;
}

Answer 1

您可以创建一个 MigrationManager 来处理迁移列表，然后让每个子模块向其注册自己的迁移。

类似

public class MigrationManager implements RealmMigration {

    List<RealmMigration> migrations = new ArrayList<>();

    public void addMigration(RealmMigration migration) {
        migrations.add(migration);
    }

    @Override
    public void migrate(DynamicRealm realm, long oldVersion, long newVersion) {
        for (RealmMigration migration : migrations) {
            migration.migrate(realm, oldVersion, newVersion);
        }
    }
}

如何支持多个 RealmMigrations

How to support multiple RealmMigrations

android

realm

android-library

realm-migration