@absinthe/socket/src/unobserveOrCancel.js

Absinthe Socket

// @flow

import cancel from "./cancel";
import unobserve from "./unobserve";

import type {AbsintheSocket} from "./types";
import type {Notifier, Observer} from "./notifier/types";

const doUnobserveOrCancel = (absintheSocket, notifier, observer) =>
  notifier.activeObservers.length === 1
    ? cancel(absintheSocket, notifier)
    : unobserve(absintheSocket, notifier, observer);

/**
 * Cancels notifier if there are no more observers apart from the one given, or
 * detaches given observer from notifier otherwise
 *
 * @example
 * import * as withAbsintheSocket from "@absinthe/socket";
 *
 * withAbsintheSocket.unobserve(absintheSocket, notifier, observer);
 */
const unobserveOrCancel = <Result, Variables: void | Object>(
  absintheSocket: AbsintheSocket,
  notifier: Notifier<Result, Variables>,
  observer: Observer<Result, Variables>
) =>
  notifier.isActive
    ? doUnobserveOrCancel(absintheSocket, notifier, observer)
    : absintheSocket;

export default unobserveOrCancel;