ember-lifeline/dist/schedule-task.js

Ember.js addon for lifecycle aware async tasks and DOM events.

import { assert } from '@ember/debug';
import { schedule } from '@ember/runloop';
import { isDestroying } from '@ember/destroyable';
import { NULL_TIMER_ID, getTimers } from './cancel-task.js';
import getTask from './utils/get-task.js';

/**
 * Adds the provided function to the named queue for the provided object. The timer is
 * properly canceled if the object is destroyed before it is invoked.
 *
 * Example:
 *
 * ```js
 * import Component from '@glimmer/component';
 * import { scheduleTask } from 'ember-lifeline';
 *
 * export default ScheduledComponent extends Component {
 *   start() {
 *     scheduleTask(this, 'actions', () => {
 *       console.log('This runs at the end of the run loop (via the actions queue) if this component is still displayed');
 *     })
 *   },
 * });
 * ```
 *
 * @function scheduleTask
 * @param { Destroyable } destroyable the instance to register the task for
 * @param { String } queueName the queue to schedule the task into
 * @param { Function | String } taskOrName a function representing the task, or string
 *                                         specifying a property representing the task,
 *                                         which is run at the provided time specified
 *                                         by timeout
 * @param { ...* } args arguments to pass to the task
 * @public
 */

function scheduleTask(destroyable, queueName, taskOrName, ...args) {
  assert(`Called \`scheduleTask\` without a string as the first argument on ${destroyable}.`, typeof queueName === 'string');
  assert(`Called \`scheduleTask\` while trying to schedule to the \`afterRender\` queue on ${destroyable}.`, queueName !== 'afterRender');

  if (isDestroying(destroyable)) {
    return NULL_TIMER_ID;
  }

  let task = getTask(destroyable, taskOrName, 'scheduleTask');
  let timers = getTimers(destroyable);
  let cancelId;

  let taskWrapper = (...taskArgs) => {
    timers.delete(cancelId);
    task.call(destroyable, ...taskArgs);
  };

  cancelId = schedule(queueName, destroyable, taskWrapper, ...args);
  timers.add(cancelId);
  return cancelId;
}

export { scheduleTask };