feat: add SQLite and PostgreSQL event queue adapters with migrations

.env.example

@@ -38,12 +38,22 @@ SECURE_COOKIES=false
 ALLOW_REGISTRATION=false
 RATE_LIMIT=20
 POSTER_FETCH_TIMEOUT_SECONDS=30
-EVENT_CHANNEL_BUFFER=128
 
-# NATS event bus (optional — falls back to in-memory channel when unset)
+# Event bus — controls background poster sync and other async work.
+# Priority: NATS (if NATS_URL set) → DB queue (default, uses existing DB)
+# The worker binary must run alongside the presentation to process events.
+
+# Option A: DB queue (default — no extra infrastructure needed)
+# Events are stored in the same database as the app and polled by the worker.
+# EVENT_QUEUE_POLL_INTERVAL_MS=500   # polling interval (default: 500ms)
+# EVENT_QUEUE_BATCH_SIZE=10          # rows claimed per poll cycle (default: 10)
+# EVENT_QUEUE_MAX_ATTEMPTS=5         # retries before dead-lettering (default: 5)
+
+# Option B: NATS (at-least-once delivery, recommended for higher throughput)
 # NATS_URL=nats://localhost:4222
 # NATS_MODE=jetstream           # "jetstream" (default, at-least-once) or "core" (fire-and-forget)
 # NATS_SUBJECT_PREFIX=movies-diary.events
 # NATS_STREAM_NAME=MOVIES_DIARY_EVENTS
 # NATS_CONSUMER_NAME=worker
-RUST_LOG=presentation=debug,tower_http=debug
+
+RUST_LOG=presentation=debug,tower_http=debug,worker=info,application=info

Dockerfile

@@ -17,10 +17,12 @@ COPY crates/adapters/poster-fetcher/Cargo.toml    crates/adapters/poster-fetcher
 COPY crates/adapters/poster-storage/Cargo.toml    crates/adapters/poster-storage/Cargo.toml
 COPY crates/adapters/export/Cargo.toml            crates/adapters/export/Cargo.toml
 COPY crates/adapters/rss/Cargo.toml               crates/adapters/rss/Cargo.toml
-COPY crates/adapters/sqlite/Cargo.toml            crates/adapters/sqlite/Cargo.toml
-COPY crates/adapters/sqlite-federation/Cargo.toml crates/adapters/sqlite-federation/Cargo.toml
-COPY crates/adapters/postgres/Cargo.toml           crates/adapters/postgres/Cargo.toml
+COPY crates/adapters/sqlite/Cargo.toml              crates/adapters/sqlite/Cargo.toml
+COPY crates/adapters/sqlite-federation/Cargo.toml   crates/adapters/sqlite-federation/Cargo.toml
+COPY crates/adapters/sqlite-event-queue/Cargo.toml  crates/adapters/sqlite-event-queue/Cargo.toml
+COPY crates/adapters/postgres/Cargo.toml            crates/adapters/postgres/Cargo.toml
 COPY crates/adapters/postgres-federation/Cargo.toml crates/adapters/postgres-federation/Cargo.toml
+COPY crates/adapters/postgres-event-queue/Cargo.toml crates/adapters/postgres-event-queue/Cargo.toml
 COPY crates/adapters/template-askama/Cargo.toml   crates/adapters/template-askama/Cargo.toml
 COPY crates/application/Cargo.toml                crates/application/Cargo.toml
 COPY crates/domain/Cargo.toml                     crates/domain/Cargo.toml

README.md

@@ -34,10 +34,14 @@ adapters/
   template-askama   — Askama HTML rendering
   rss               — RSS/Atom feed generation
   export            — CSV and JSON diary serialization
-  event-publisher   — async event channel for background poster sync
-  activitypub       — ActivityPub federation (follow, inbox/outbox, actor)
-  activitypub-base  — core ActivityPub types and repository traits
+  sqlite-event-queue   — polling event queue backed by SQLite (DB-queue mode)
+  postgres-event-queue — polling event queue backed by PostgreSQL (DB-queue mode)
+  nats                 — NATS Core / JetStream event publisher and consumer
+  event-publisher      — in-memory event channel (used in tests)
+  activitypub          — ActivityPub federation (follow, inbox/outbox, actor)
+  activitypub-base     — core ActivityPub types and repository traits
 doc                 — OpenAPI spec assembly and Swagger UI / Scalar serving
+worker              — standalone worker binary (polls the event queue, syncs posters)
 tui                 — terminal UI client (ratatui)
 ```
 
@@ -85,16 +89,28 @@ PORT=3000
 RATE_LIMIT=60           # requests per minute per IP (default: 60)
 ALLOW_REGISTRATION=true # set to false to disable new sign-ups
 SECURE_COOKIES=true     # set when serving over HTTPS
-RUST_LOG=presentation=info,tower_http=info
+RUST_LOG=presentation=info,tower_http=info,worker=info,application=info
+
+# Event bus — background poster sync runs in the worker binary.
+# Default: DB queue (uses the same database, no extra infrastructure).
+# Set NATS_URL to use NATS instead (JetStream recommended for at-least-once delivery).
+# NATS_URL=nats://localhost:4222
+```
+
+The `worker` binary must run alongside `presentation` to process events:
+
+```bash
+cargo run -p worker
 ```
 
 ## Run
 
 ```bash
-cargo run -p presentation
+cargo run -p presentation   # HTTP server (0.0.0.0:3000)
+cargo run -p worker         # event worker (poster sync, in a separate terminal)
 ```
 
-Server listens on `0.0.0.0:3000` by default.
+The worker polls the event queue and must run alongside the presentation to process background tasks like poster fetching. Both processes share the same database.
 
 ## API
 

crates/adapters/postgres-event-queue/Cargo.toml

@@ -4,7 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-sqlx        = { version = "0.8.6", features = ["runtime-tokio-rustls", "postgres", "macros", "chrono", "uuid"] }
+sqlx        = { version = "0.8.6", features = ["runtime-tokio-rustls", "postgres", "macros", "chrono"] }
 domain      = { workspace = true }
 anyhow      = { workspace = true }
 async-trait = { workspace = true }

crates/adapters/postgres-event-queue/src/migrations.rs

@@ -1,5 +1,6 @@
 pub(crate) async fn run(pool: &sqlx::PgPool) -> anyhow::Result<()> {
     sqlx::migrate!("./migrations")
+        .set_ignore_missing(true)
         .run(pool)
         .await
         .map_err(|e| anyhow::anyhow!("postgres-event-queue migration failed: {e}"))

crates/adapters/postgres/src/lib.rs

@@ -57,6 +57,7 @@ impl PostgresRepository {
 
     pub async fn migrate(&self) -> Result<(), DomainError> {
         sqlx::migrate!("./migrations")
+            .set_ignore_missing(true)
             .run(&self.pool)
             .await
             .map_err(|e| DomainError::InfrastructureError(format!("Migration failed: {}", e)))

crates/adapters/sqlite-event-queue/src/migrations.rs

@@ -1,5 +1,6 @@
 pub(crate) async fn run(pool: &sqlx::SqlitePool) -> anyhow::Result<()> {
     sqlx::migrate!("./migrations")
+        .set_ignore_missing(true)
         .run(pool)
         .await
         .map_err(|e| anyhow::anyhow!("sqlite-event-queue migration failed: {e}"))

crates/adapters/sqlite/src/migrations.rs

@@ -3,6 +3,7 @@ use sqlx::SqlitePool;
 
 pub(crate) async fn run(pool: &SqlitePool) -> Result<(), DomainError> {
     sqlx::migrate!("./migrations")
+        .set_ignore_missing(true)
         .run(pool)
         .await
         .map_err(|e| DomainError::InfrastructureError(e.to_string()))