nats adapter

crates/presentation/Cargo.toml

@@ -9,8 +9,18 @@ sqlite = ["dep:sqlite"]
 postgres = ["dep:postgres"]
 # Meta-feature: true when any federation adapter is active — keeps all #[cfg(feature = "federation")] gates working
 federation = []
-sqlite-federation = ["sqlite", "dep:sqlite-federation", "dep:activitypub", "federation"]
-postgres-federation = ["postgres", "dep:postgres-federation", "dep:activitypub", "federation"]
+sqlite-federation = [
+    "sqlite",
+    "dep:sqlite-federation",
+    "dep:activitypub",
+    "federation",
+]
+postgres-federation = [
+    "postgres",
+    "dep:postgres-federation",
+    "dep:activitypub",
+    "federation",
+]
 
 [dependencies]
 tower-http = { version = "0.6.8", features = ["fs", "trace", "tracing"] }
@@ -39,6 +49,7 @@ poster-fetcher = { workspace = true }
 poster-storage = { workspace = true }
 template-askama = { workspace = true }
 event-publisher = { workspace = true }
+nats = { workspace = true }
 rss = { workspace = true }
 export = { workspace = true }
 doc = { workspace = true }
@@ -46,12 +57,12 @@ sqlx = { workspace = true }
 utoipa = { version = "5.5.0", features = ["axum_extras", "uuid"] }
 
 # Optional — database backends
-sqlite              = { workspace = true, optional = true }
-postgres            = { workspace = true, optional = true }
+sqlite = { workspace = true, optional = true }
+postgres = { workspace = true, optional = true }
 
 # Optional — federation
-activitypub         = { workspace = true, optional = true }
-sqlite-federation   = { workspace = true, optional = true }
+activitypub = { workspace = true, optional = true }
+sqlite-federation = { workspace = true, optional = true }
 postgres-federation = { workspace = true, optional = true }
 
 [dev-dependencies]

crates/presentation/src/main.rs

@@ -38,9 +38,9 @@ use presentation::{openapi::ApiDoc, routes, state::AppState};
 use utoipa::OpenApi as _;
 
 use domain::ports::{
-    AuthService, DiaryExporter, DiaryRepository, MetadataClient, MovieRepository,
-    PasswordHasher, PosterFetcherClient, PosterStorage, ReviewRepository, StatsRepository,
-    UserRepository,
+    AuthService, DiaryExporter, DiaryRepository, EventHandler, EventPublisher, MetadataClient,
+    MovieRepository, PasswordHasher, PosterFetcherClient, PosterStorage, ReviewRepository,
+    StatsRepository, UserRepository,
 };
 
 #[cfg(not(any(feature = "sqlite", feature = "postgres")))]
@@ -184,26 +184,18 @@ async fn wire_dependencies() -> anyhow::Result<(AppState, axum::Router)> {
         );
         let ap_service_arc: Arc<dyn ActivityPubPort> = concrete_ap_service;
 
-        let poster_handler = Arc::new(PosterSyncHandler::new(handler_ctx, 3));
-        let (event_publisher, consumer) = create_event_channel(EventPublisherConfig::from_env());
-        let worker = WorkerService::new(
-            Arc::new(consumer),
-            vec![poster_handler, Arc::new(ap_event_handler)],
-        );
-        tokio::spawn(worker.run());
-
-        let ep: Arc<dyn domain::ports::EventPublisher> = Arc::new(event_publisher);
+        let ep = build_event_publisher(
+            handler_ctx,
+            vec![Arc::new(ap_event_handler) as Arc<dyn EventHandler>],
+        ).await?;
         (ep, ap_router, ap_service_arc, social_query_arc)
     };
 
     #[cfg(not(feature = "federation"))]
-    let (event_publisher_arc, ap_router): (Arc<dyn domain::ports::EventPublisher>, axum::Router) = {
-        let poster_handler = Arc::new(PosterSyncHandler::new(handler_ctx, 3));
-        let (event_publisher, consumer) = create_event_channel(EventPublisherConfig::from_env());
-        let worker = WorkerService::new(Arc::new(consumer), vec![poster_handler]);
-        tokio::spawn(worker.run());
-        (Arc::new(event_publisher), axum::Router::new())
-    };
+    let (event_publisher_arc, ap_router): (Arc<dyn EventPublisher>, axum::Router) = (
+        build_event_publisher(handler_ctx, vec![]).await?,
+        axum::Router::new(),
+    );
 
     let app_ctx = AppContext {
         movie_repository,
@@ -302,6 +294,23 @@ async fn wire_postgres(database_url: &str) -> anyhow::Result<(
     Ok((pool, movie_repository, review_repository, diary_repository, stats_repository, user_repository))
 }
 
+async fn build_event_publisher(
+    handler_ctx: AppContext,
+    extra_handlers: Vec<Arc<dyn EventHandler>>,
+) -> anyhow::Result<Arc<dyn EventPublisher>> {
+    if let Ok(cfg) = nats::NatsConfig::from_env() {
+        tracing::info!("event bus: NATS ({})", cfg.url);
+        return nats::create_publisher(cfg).await;
+    }
+    tracing::info!("event bus: in-memory");
+    let poster_handler = Arc::new(PosterSyncHandler::new(handler_ctx, 3));
+    let mut handlers: Vec<Arc<dyn EventHandler>> = vec![poster_handler];
+    handlers.extend(extra_handlers);
+    let (publisher, consumer) = create_event_channel(EventPublisherConfig::from_env());
+    tokio::spawn(WorkerService::new(Arc::new(consumer), handlers).run());
+    Ok(Arc::new(publisher))
+}
+
 fn init_tracing() {
     tracing_subscriber::registry()
         .with(tracing_subscriber::EnvFilter::new(