Class LifeCycleObserverRegistry

packages/core/src/lifecycle-registry.ts:58–268

 * A context-based registry for life cycle observers
 */
export class LifeCycleObserverRegistry implements LifeCycleObserver {
  constructor(
    @inject.context()
    protected readonly context: Context,
    @inject.view(lifeCycleObserverFilter)
    protected readonly observersView: ContextView<LifeCycleObserver>,
    @inject(CoreBindings.LIFE_CYCLE_OBSERVER_OPTIONS, {optional: true})
    protected readonly options: LifeCycleObserverOptions = {
      parallel: true,
      orderedGroups: DEFAULT_ORDERED_GROUPS,
    },
  ) {}

  setOrderedGroups(groups: string[]) {
    this.options.orderedGroups = groups;
  }

  /**
   * Get observer groups ordered by the group
   */
  public getObserverGroupsByOrder(): LifeCycleObserverGroup[] {
    const bindings = this.observersView.bindings;
    const groups = this.sortObserverBindingsByGroup(bindings);
    if (debug.enabled) {
      debug(
        'Observer groups: %j',
        groups.map(g => ({
          group: g.group,
          bindings: g.bindings.map(b => b.key),
        })),
      );
    }
    return groups;
  }

  /**
   * Get the group for a given life cycle observer binding
   * @param binding - Life cycle observer binding
   */
  protected getObserverGroup(
    binding: Readonly<Binding<LifeCycleObserver>>,
  ): string {
    // First check if there is an explicit group name in the tag
    let group = binding.tagMap[CoreTags.LIFE_CYCLE_OBSERVER_GROUP];
    if (!group) {
      // Fall back to a tag that matches one of the groups
      group = this.options.orderedGroups.find(g => binding.tagMap[g] === g);
    }
    group = group || '';
    debug(
      'Binding %s is configured with observer group %s',
      binding.key,
      group,
    );
    return group;
  }

  /**