MobX store with actions

action.js

export class ContactStore {
	@observable contacts = [];
	@observable pendingRequestCount = 0;

	@computed get isLoading() {
		return this.pendingRequestCount > 0;
	}

	@action	createRandomContact() {
		this.pendingRequestCount++;
		superagent.get('https://randomuser.me/api/').end(
			action("createRandomContact-callback", (error, results) => {
				const contact = new Contact(results[0])
				this.contacts.push(contact);
				this.pendingRequestCount--;
			})
		);
	}
}