feat: worker relays outbox to nats

crates/adapters/nats/src/tests/consumer.rs

@@ -0,0 +1,46 @@
+use super::*;
+use domain::value_objects::UserId;
+use event_payload::{EventMessage, EventPayload};
+use uuid::Uuid;
+
+fn payload() -> EventPayload {
+    EventPayload::from(&DomainEvent::UserUpdated {
+        user_id: UserId::from_uuid(Uuid::new_v4()),
+    })
+}
+
+fn encode(event_id: Option<&str>) -> Vec<u8> {
+    serde_json::to_vec(&EventMessage {
+        event_id: event_id.map(str::to_owned),
+        payload: payload(),
+    })
+    .unwrap()
+}
+
+#[test]
+fn decode_message_reads_the_event_id() {
+    let id = Uuid::new_v4();
+    let (decoded, event) = decode_message(&encode(Some(&id.to_string()))).unwrap();
+    assert_eq!(decoded.unwrap().value(), id);
+    assert!(matches!(event, DomainEvent::UserUpdated { .. }));
+}
+
+#[test]
+fn decode_message_accepts_a_legacy_payload_without_an_id() {
+    let legacy = serde_json::to_vec(&payload()).unwrap();
+    let (decoded, _) = decode_message(&legacy).unwrap();
+    assert!(decoded.is_none());
+    let (decoded, _) = decode_message(&encode(None)).unwrap();
+    assert!(decoded.is_none());
+}
+
+#[test]
+fn decode_message_rejects_a_malformed_id() {
+    let err = decode_message(&encode(Some("not-a-uuid"))).unwrap_err();
+    assert!(err.to_string().contains("event_id"), "{err}");
+}
+
+#[test]
+fn decode_message_rejects_garbage() {
+    assert!(decode_message(b"{not json").is_err());
+}

crates/adapters/nats/src/tests/relay.rs

@@ -0,0 +1,37 @@
+use super::*;
+use domain::value_objects::UserId;
+use uuid::Uuid;
+
+fn event() -> DomainEvent {
+    DomainEvent::UserUpdated {
+        user_id: UserId::from_uuid(Uuid::new_v4()),
+    }
+}
+
+#[test]
+fn relaying_the_same_row_twice_sets_the_same_msg_id() {
+    let id = EventId::new();
+    let event = event();
+    let first = relay_message("p", Some(&id), &event).unwrap();
+    let second = relay_message("p", Some(&id), &event).unwrap();
+    assert_eq!(first.msg_id, Some(id.value().to_string()));
+    assert_eq!(first.msg_id, second.msg_id);
+    assert_eq!(first.subject, "p.user.updated");
+}
+
+#[test]
+fn a_legacy_row_without_an_id_has_no_msg_id() {
+    let message = relay_message("p", None, &event()).unwrap();
+    assert_eq!(message.msg_id, None);
+    let decoded: serde_json::Value = serde_json::from_slice(&message.payload).unwrap();
+    assert!(decoded.get("event_id").is_none());
+}
+
+#[test]
+fn the_body_carries_the_event_id_for_the_consumer() {
+    let id = EventId::new();
+    let message = relay_message("p", Some(&id), &event()).unwrap();
+    let decoded: serde_json::Value = serde_json::from_slice(&message.payload).unwrap();
+    assert_eq!(decoded["event_id"], id.value().to_string());
+    assert_eq!(decoded["type"], "UserUpdated");
+}