apollo-offline

Apollo 2.0 Implementation allowing for offline mutations.

Installation

To get started with ApolloOfflineClient, install using your favorite package manager (yarn or npm):

$ yarn add @wellth/apollo-offline
$ npm install @wellth/apollo-offline

Usage

Apollo offline client is intended to be used as a drop-in replacement for existing apollo 2.0 infrastructure:

/// Configure your cache as usual
const cache = new InMemoryCache({ ... });

const apiClient = new ApolloOfflineClient({
   middleware,
   offlineLinks: [
     /// Links to be executed whether or not the request hits the network.
     /// Usually side-effects and logging.
     new LoggerLink(),
     new ErrorLink(),
  ],
  onlineLinks: [
    /// Links to be executed only if the request is meant for the network.
    /// This includes any header modifications,
    /// splitting based on context, etc.
    new AuthenticationLink({
      getAuthToken: () => selectAuthToken(store.getState()),
      setAuthToken: token => store.dispatch(setAuthToken(token))
    }),
    new HttpLink({
      uri,
    }),
  ],
  persistCallback: () => {
    store.dispatch({ type: REHYDRATE_STORE });
  }
}, { cache })

/// Use as you would any other `ApolloClient`.

The ApolloOfflineClient creates a "fractured" network-stack. That is, it configures an "offline" link for handling offline requests.

Offline Behavior

If the client determines that the network is offline, it will execute all links in offlineLinks, but it will "dead-end" at the offline link.

To skip the offline link on a per-request basis (i.e. "authentication calls can only be made online") add requireOnline: true to the context of the request.

Queries

Queries executed while offline will read and return the optimistic response from the cache, or null.

Mutations

All mutations will be queued, persisted, and executed via redux-offline.

Executed mutations will be "processed" (queued to redux-offline) and will return the optimisticResponse.

Online Behavior

If the client determines that the network is online, it will execute all links in offlineLinks and onlineLinks.

The @redux-offline implementation will push any queued mutations through the client like client.mutate(options)

Queries

Queries executed while offline will not be processed by the offline reducer, and will be forwarded along the link chain.

Mutations

See offline behavior for mutations.

Mutations executed while online will be "processed" like offline mutations to ensure data consistency, and executed the same way.

This means that after executing a mutation, it will respond twice. It will return the optimistic response if any (processing), and then it will respond with the network data.

Coming Soon

• [] Fetching items from the queued, offline-cache
• [] Flagging optimistic responses