Dispatcher Task¶

namespace Dispatcher¶

Dispatcher task management and control functions.

The dispatcher is a dedicated FreeRTOS task that processes all reactive updates. All Computed nodes and Effect nodes are enqueued to the dispatcher for execution.

Since: v0.1.0

Note

Must call start() before using any reactive nodes.

Functions¶

inline Status start()¶

Start the dispatcher task and queue.

Creates the FreeRTOS dispatcher task and initializes all priority queues. Must be called before using any reactive nodes (Signal / Computed / Effect).

Since: v0.1.0

Signal<int> counter(0);
Computed<int> doubled([]() { return counter.get() * 2; });

void setup() {
  Serial.begin(115200);

  if (!Dispatcher::start()) {
    Serial.println("Failed to start dispatcher!");
    while(1) delay(1000);
  }

  // Now safe to use reactive nodes
  counter.set(1);
}

Returns:¶: Status::Ok on success, error code on failure.

inline TaskHandle_t getTaskHandle()¶

Get the task handle of the dispatcher task.

Returns the FreeRTOS task handle for the dispatcher task. Useful for monitoring or integrating with other RTOS features.

Since: v0.1.0

TaskHandle_t handle = Dispatcher::getTaskHandle();

if (handle != nullptr) {
  UBaseType_t priority = uxTaskPriorityGet(handle);
  Serial.printf("Dispatcher priority: %u\n", priority);
}

Returns:¶: TaskHandle_t of the dispatcher task, nullptr if not started.

inline Status wake(bool from_isr = false)¶

Wake the dispatcher task to process pending work.

Immediately wakes the dispatcher task to process queued reactive updates. Useful when using queueToSignal() or when manual waking is needed.

Since: v0.1.0

// From normal task context
Signal<int> signal(0);
QueueHandle_t sensor_queue = xQueueCreate(10, sizeof(int));
Helpers::Utility::queueToSignal(sensor_queue, signal);

int value = 123;
xQueueSend(sensor_queue, &value, portMAX_DELAY);
Dispatcher::wake(); // Wake up dispatcher to process the signal update

// From ISR context
void IRAM_ATTR onInterrupt() {
  int data = readSensor();
  BaseType_t task_woken = pdFALSE;
  xQueueSendFromISR(queue, &data, &task_woken);
  Dispatcher::wake(true); // Wake up dispatcher from ISR
}

Parameters:¶

bool from_isr = false¶: Set to true if calling from an ISR context.

Returns:¶

Status::Ok on success, error code on failure.

inline Status pauseReactivity()¶

Pause all reactive updates globally.

Suspends the dispatcher task, preventing all Computed and Effect nodes from executing. Signals can still be modified, but no reactive updates will occur until resumeReactivity() is called.

Since: v0.1.0

// Batch multiple signal updates without triggering reactive updates
Dispatcher::pauseReactivity();

signal1.set(10);  // No reactive updates
signal2.set(20);  // No reactive updates
signal3.set(30);  // No reactive updates

Dispatcher::resumeReactivity(); // All dependents updated now

Note

Signals remain modifiable and track changes while paused. All dependents updates execute when resumeReactivity() is called.

Warning

Pausing reactivity for extended periods may lead to missed updates if the dispatcher event queue becomes full (RXESP32_DISPATCHER_QUEUE_LENGTH).

Returns:¶: Status::Ok on success, error code on failure.

inline Status resumeReactivity()¶

Resume reactive updates after pauseReactivity().

Resumes the dispatcher task and wakes it to process any pending updates that occurred while paused.

Since: v0.1.0

Dispatcher::pauseReactivity();
// ... batch changes ...
Dispatcher::resumeReactivity(); // Process all pending updates

Returns:¶: Status::Ok on success, error code on failure.

Dispatcher Task¶

See Also¶