flowable/flowable-engine · error · FlowableObjectNotFoundException

Could not find a event subscription with id

Error message

Could not find a event subscription with id '${eventSubscriptionId}'.

What it means

Thrown by the CMMN REST API when a GET request for an event subscription by ID matches no rows in the runtime event subscription table. Flowable's EventSubscriptionResource queries runtimeService.createEventSubscriptionQuery().id(id).singleResult() and, per REST convention, maps a null result to FlowableObjectNotFoundException with EventSubscription.class as the resource type. It signals the requested ID does not exist (or no longer exists) at runtime.

Solutions

1. Verify the eventSubscriptionId exists via GET /cmmn-runtime/event-subscriptions (collection query) or query ACT_RU_EVENT_SUBSCR.
2. Re-fetch the case instance's plan items/event subscriptions right before use, since subscriptions are transient and deleted once signaled.
3. Confirm you are connected to the correct database/tenant where the case is running.
4. Handle FlowableObjectNotFoundException (404) in the client and treat it as 'subscription no longer active' rather than retrying.

Example fix

// before
EventSubscriptionResponse resp = client.get("/cmmn-runtime/event-subscriptions/" + staleId);
// after
List<EventSubscriptionResponse> subs = client.get("/cmmn-runtime/event-subscriptions?caseInstanceId=" + caseId);
if (subs.isEmpty()) { /* subscription gone; re-derive or skip */ }

// pre-check
EventSubscriptionResponse s = rest.get("/cmmn-runtime/event-subscriptions?caseInstanceId=" + caseId)
    .stream().filter(e -> e.getId().equals(subId)).findFirst().orElse(null);
if (s == null) throw new IllegalStateException("event subscription gone: " + subId);

function subscriptionExists(sub) { return sub && typeof sub.id === 'string' && sub.id.length > 0; }

try { return api.getEventSubscription(id); }
catch (FlowableObjectNotFoundException e) {
  if (e.getResourceClass() == EventSubscription.class) { refreshCaseSubscriptions(); return null; }
  throw e;
}

When it happens

Trigger: GET /cmmn-runtime/event-subscriptions/{eventSubscriptionId} with an ID that was never created, was already consumed/cancelled (event subscriptions are deleted once signaled), or belongs to a completed/deleted case instance.

Common situations: Client cached an ID from a previous run against a different database; event subscription was consumed by a signal/message receipt between listing and fetching; querying against wrong tenant/datasource; case instance ended and its subscriptions were removed; typo in the ID.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

• Could not find a event subscription with id
• Could not find a plan item instance with id
• Plan item instance ' ' does not have a variable ' ' in…
• Task '
• An assignee is required when delegating a task.

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/a1803dd91ceabaad. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-cmmn-rest/src/main/java/org/flowable/cmmn/rest/service/api/runtime/caze/EventSubscriptionResource.java:59

    protected CmmnRestResponseFactory restResponseFactory;

    @Autowired
    protected CmmnRuntimeService runtimeService;
    
    @Autowired(required=false)
    protected CmmnRestApiInterceptor restApiInterceptor;

    @ApiOperation(value = "Get a single event subscription", tags = { "Event subscriptions" })
    @ApiResponses(value = {
            @ApiResponse(code = 200, message = "Indicates the event subscription exists and is returned."),
            @ApiResponse(code = 404, message = "Indicates the requested event subscription does not exist.")
    })
    @GetMapping(value = "/cmmn-runtime/event-subscriptions/{eventSubscriptionId}", produces = "application/json")
    public EventSubscriptionResponse getEventSubscription(@ApiParam(name = "eventSubscriptionId") @PathVariable String eventSubscriptionId) {
        EventSubscription eventSubscription = runtimeService.createEventSubscriptionQuery().id(eventSubscriptionId).singleResult();

        if (eventSubscription == null) {
            throw new FlowableObjectNotFoundException("Could not find a event subscription with id '" + eventSubscriptionId + "'.", EventSubscription.class);
        }
        
        if (restApiInterceptor != null) {
            restApiInterceptor.accessEventSubscriptionById(eventSubscription);
        }

        return restResponseFactory.createEventSubscriptionResponse(eventSubscription);
    }
}

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