flowable/flowable-engine · error · FlowableException

Message dispatcher is disabled, cannot dispatch

Error message

Message dispatcher is disabled, cannot dispatch ${event}

What it means

DispatchEventCommand requires an enabled event dispatcher: if the engine's FlowableEventDispatcher is null or disabled (isEnableEventDispatcher() false), the event cannot be delivered and this FlowableException is thrown instead of silently dropping the event.

Solutions

1. Enable the event dispatcher in configuration: setEnableEventDispatcher(true) (or event registry equivalent) on ProcessEngineConfiguration.
2. Verify configuration at startup — processEngineConfiguration.getEventDispatcher() != null && isEnabled().
3. If events are intentionally unused, remove or guard the dispatch calls instead of expecting silent no-ops.
4. Check the deployed config file/Spring beans for a conflicting event-dispatcher=false property.

Example fix

// before
ProcessEngineConfigurationImpl cfg = ...; // event dispatcher disabled
cfg.setEnableEventDispatcher(false);
runtimeService.dispatchEvent(event); // throws
// after
cfg.setEnableEventDispatcher(true);
runtimeService.dispatchEvent(event);

ProcessEngineConfigurationImpl cfg = ...;
if (cfg.getEventDispatcher() == null || !cfg.getEventDispatcher().isEnabled()) {
    throw new IllegalStateException("Event dispatcher must be enabled to dispatch events");
}

try { rs.dispatchEvent(event); } catch (FlowableException e) { log.warn("Dispatcher disabled, event dropped: {}", event); }

When it happens

Trigger: Calling runtimeService.dispatchEvent(event) when eventDispatcher is null or isEnabled() is false — e.g. the engine config didn't enable the event registry/dispatcher, or the deployed configuration created a dispatcher-less engine.

Common situations: Lightweight/embedded engine configs where event dispatch was disabled for performance; tests using minimal config; event listeners expected but useEventDispatcher/enableEventDispatcher never set true; Spring config missing the eventRegistry initializer.

Related errors

• event is null
• No formEngine '' defined process engine configuration
• No formEngine '' defined process engine configuration
• A channel key detection value is required for the channel…
• A datasource is required for initializing the engine

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/5977d5c10c13067f. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-engine/src/main/java/org/flowable/engine/impl/cmd/DispatchEventCommand.java:48

    protected FlowableEvent event;

    public DispatchEventCommand(FlowableEvent event) {
        this.event = event;
    }

    @Override
    public Void execute(CommandContext commandContext) {
        if (event == null) {
            throw new FlowableIllegalArgumentException("event is null");
        }

        ProcessEngineConfigurationImpl processEngineConfiguration = CommandContextUtil.getProcessEngineConfiguration(commandContext);
        FlowableEventDispatcher eventDispatcher = processEngineConfiguration.getEventDispatcher();
        if (eventDispatcher != null && eventDispatcher.isEnabled()) {
            eventDispatcher.dispatchEvent(event, processEngineConfiguration.getEngineCfgKey());
        } else {
            throw new FlowableException("Message dispatcher is disabled, cannot dispatch " + event);
        }

        return null;
    }

}

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