fix: catch unhandled rejection from dispatcher polling loop - #204
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GiovaniGuizzo merged 1 commit intoJul 21, 2026
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start() called void this.listen() with no .catch(). listen() awaits
DB calls without a try/catch, so a transient connection error causes
the loop to exit and the rejection to surface as an unhandled rejection.
In Node >= 15 this crashes the process; in older Node it silently kills
the polling loop and jobs pile up in waiting state with no recovery.
The same file already handles this correctly for job execution:
void this.executorManager.execute(queue, job).catch((error: unknown) => {
logger("Dispatcher").error(`Unexpected error executing job ${job.id}:`, error);
});
Apply the same pattern to start().
GiovaniGuizzo
approved these changes
Jul 20, 2026
merencia
approved these changes
Jul 21, 2026
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Summary
`Dispatcher.start()` calls `void this.listen()` without a `.catch()`. The `listen()` loop awaits DB calls that can throw on a transient connection error. When that happens, the rejected promise surfaces as an unhandled rejection — crashing the process in Node ≥ 15, or silently killing the polling loop in older Node (jobs stall in waiting state with no recovery).
The same file already handles this correctly for job execution:
```ts
void this.executorManager.execute(queue, job).catch((error: unknown) => {
logger("Dispatcher").error(`Unexpected error executing job ${job.id}:`, error);
});
```
Fix
Apply the same pattern to `start()`:
```ts
void this.listen().catch((error: unknown) => {
logger("Dispatcher").error("Dispatcher polling loop crashed unexpectedly:", error);
});
```
A follow-up could wrap the `while` body in try/catch to recover from transient errors without restarting the whole loop, but this `.catch()` prevents the process crash in the meantime.