/apollo-link-queue

A link to queue GraphQL requests when offline

Primary LanguageTypeScriptMIT LicenseMIT

apollo-link-queue

An Apollo Link that acts as a gate and queues requests when the gate is closed. This can be used when there is no internet connection or when the user has explicitly set an app to offline mode.

Installation

yarn add apollo-link-queue@https://github.com/unchartedsoftware/apollo-link-queue/

Usage

import QueueLink from 'apollo-link-queue';

const queueLink = new QueueLink();

// To start queueing requests
queueLink.close();

// To let requests pass (and execute all queued requests)
queueLink.open();

Optional filtering

import QueueLink from 'apollo-link-queue';

const queueLink = new QueueLink();

// Optionally only queue mutations
QueueLink.setFilter(['mutation']);

// To start queueing requests
queueLink.close();

// To let requests pass (and execute all queued requests)
queueLink.open();

Link Queue Event Listeners

Listeners allow for a system outside to be notified when an enqueue or dequeue event occurrs. You can register a listener for a specific operation name or pass the keyword "any" to listen to all operations using the static method QueueLink.addLinkQueueEventListener().

QueueLink.addLinkQueueEventListener() takes the following parameters: - Operation name to listen to. Valid values are any or an actual operation name string from the mutation or query you want to be alerted on. - The enqueue or dequeue string to specify which event to listen to, - A callback function that takes a single parameter which will be the operation from the queue that is being acted upon.

    QueueLink.addLinkQueueEventListener("insert_myObject", "enqueue", (item: any) => {
      console.log('QueueLink listener (insert_myObject, enqueued) fired with item: ', item);
    });

    QueueLink.addLinkQueueEventListener("insert_myObject", "dequeue", (item: any) => {
      console.log('QueueLink listener (insert_myObject, dequeue) fired with item: ', item);
    });
    QueueLink.addLinkQueueEventListener("any", "enqueue", (item: any) => {
      console.log('QueueLink listener (any, enqueued) fired with item: ', item);
    });

    QueueLink.addLinkQueueEventListener("any", "dequeue", (item: any) => {
      console.log('QueueLink listener (any, dequeue) fired with item: ', item);
    });

Offline mode example with queueing and retry

import { ApolloLink } from 'apollo-link';
import { HttpLink } from 'apollo-link-http';
import { RetryLink } from 'apollo-link-retry';

import QueueLink from 'apollo-link-queue';

const offlineLink = new QueueLink();

// Note: remove these listeners when your app is shut down to avoid leaking listeners.
window.addEventListener('offline', () => offlineLink.close());
window.addEventListener('online', () => offlineLink.open());

this.link = ApolloLink.from([
    new RetryLink(),
    offlineLink,
    new HttpLink({ uri: URI_TO_YOUR_GRAPHQL_SERVER }),
]);