Function update

final/client/src/containers/action-button.tsx:36–53

(cache, { data: { cancelTrip } })

    {
      variables: { launchId: id },
      update(cache, { data: { cancelTrip } }) {
        // Update the user's cached list of trips to remove the trip that
        // was just canceled.
        const launch = cancelTrip.launches[0];
        cache.modify({
          id: cache.identify({
            __typename: 'User',
            id: localStorage.getItem('userId'),
          }),
          fields: {
            trips(existingTrips: Reference[], { readField }) {
              return existingTrips.filter(
                tripRef => readField("id", tripRef) !== launch.id
              );
            }
          }
        });
      }
    }
  );