fix: include actual error message in replaceable event rejection responses

.changeset/replaceable-event-error-message-empty.md

@@ -0,0 +1,11 @@
+---
+"nostream": patch
+---
+
+fix: include the actual error message in replaceable event rejection responses
+
+`ReplaceableEventStrategy.execute()` sent clients a bare `error: ` command result
+(with no message body) whenever `eventRepository.upsert()` failed for a reason other
+than a duplicate event id. The underlying `error.message` was caught but never
+included in the response, leaving clients with no actionable information about why
+the event was rejected. The command result now includes `error.message`.

src/handlers/event-strategies/replaceable-event-strategy.ts

@@ -32,7 +32,10 @@ export class ReplaceableEventStrategy implements IEventStrategy<Event, Promise<v
           return
         }
 
-        this.webSocket.emit(WebSocketAdapterEvent.Message, createEventCommandResult(event.id, false, 'error: '))
+        this.webSocket.emit(
+          WebSocketAdapterEvent.Message,
+          createEventCommandResult(event.id, false, `error: ${error.message}`),
+        )
       }
     }
   }

test/unit/handlers/event-strategies/replaceable-event-strategy.spec.ts

@@ -88,7 +88,7 @@ describe('ReplaceableEventStrategy', () => {
     })
 
     it('rejects if unable to upsert event', async () => {
-      const error = new Error()
+      const error = new Error('connection lost')
       eventRepositoryUpsertStub.rejects(error)
 
       await strategy.execute(event)
@@ -98,7 +98,7 @@ describe('ReplaceableEventStrategy', () => {
         'OK',
         'id',
         false,
-        'error: ',
+        'error: connection lost',
       ])
     })
   })