Persistence

Device registrations are stored through IPushRepository. The default is in-memory; for production use the Shiny.DocumentDb-backed repository (or implement your own).

In-memory (default)

If you don’t configure a repository, a thread-safe in-memory store is used — ideal for tests, samples, and single-node development. Registrations are lost on restart.

Shiny.DocumentDb

Shiny.Extensions.Push.DocumentDb implements IPushRepository over Shiny.DocumentDb, so it runs on any DocumentDb backend (SQLite, PostgreSQL, SQL Server, Cosmos, MongoDB, …).

using Shiny.Extensions.Push.DocumentDb;
using Shiny.DocumentDb.Sqlite;

services.AddPushNotifications(push =>
{
    push.AddApns(o => { /* … */ });

    // registers the document store for you
    push.UseDocumentDb(o => o.DatabaseProvider = new SqliteDatabaseProvider("Data Source=push.db"));

    // …or, if you already registered IDocumentStore via services.AddDocumentStore(…):
    // push.UseDocumentDb();
});

Switch backends by changing the DatabaseProvider — e.g. new PostgreSqlDatabaseProvider("Host=…").

Behavior

• Token-keyed writes are O(1) — save, remove, and token rotation are point operations keyed on {Platform}|{DeviceToken}, the calls the manager makes constantly while pruning and rotating.
• Targeted sends stream the type and filter in-process. This keeps the repository fully AOT-safe (no JSON-path predicate translation, so no coupling to the store’s serializer naming) and provider-agnostic. For very large tables, pushing equality clauses down into the store query is a planned optimization.
• AOT-safe — the repository ships its own source-generated JSON context and passes JsonTypeInfo<T> on every store call.

Custom repository

Implement IPushRepository and register it with push.UseRepository<T>():

public sealed class MyRepository : IPushRepository
{
    public Task Save(DeviceRegistration registration, CancellationToken ct = default) { /* upsert */ }
    public Task<bool> Remove(string deviceToken, DevicePlatform platform, CancellationToken ct = default) { /* … */ }
    public Task UpdateToken(string oldToken, DevicePlatform platform, string newToken, CancellationToken ct = default) { /* … */ }
    public Task<IReadOnlyList<DeviceRegistration>> GetRegistrations(PushFilter filter, CancellationToken ct = default) { /* … */ }
    public IAsyncEnumerable<DeviceRegistration> StreamRegistrations(PushFilter filter, CancellationToken ct = default) { /* … */ }
}

services.AddPushNotifications(push => push.UseRepository<MyRepository>());

Prefer a stable DeviceId on registrations so re-registration upserts instead of creating duplicates, and implement the repository to be safe for concurrent reads/writes (the manager prunes/rotates while iterating).