How to use the apify-shared/consts.ENV_VARS.LOCAL_STORAGE_DIR function in apify-shared

export const ensureTokenOrLocalStorageEnvExists = (storageName) => {
    if (!process.env[ENV_VARS.LOCAL_STORAGE_DIR] && !process.env[ENV_VARS.TOKEN]) {
        throw new Error(`Cannot use ${storageName} as neither ${ENV_VARS.LOCAL_STORAGE_DIR} nor ${ENV_VARS.TOKEN} environment variable is set. You need to set one these variables in order to enable data storage.`); // eslint-disable-line max-len
    }
};

it('should work', async () => {
            const mock = sinon.mock(utils);

            process.env[ENV_VARS.LOCAL_STORAGE_DIR] = LOCAL_STORAGE_DIR;

            mock.expects('openLocalStorage').once();
            await Apify.openKeyValueStore();

            mock.expects('openLocalStorage').once();
            Apify.openKeyValueStore('xxx');
            mock.expects('openRemoteStorage').once();
            Apify.openKeyValueStore('xxx', { forceCloud: true });

            delete process.env[ENV_VARS.LOCAL_STORAGE_DIR];
            process.env[ENV_VARS.TOKEN] = 'xxx';

            mock.expects('openRemoteStorage').once();
            await Apify.openKeyValueStore();

            delete process.env[ENV_VARS.TOKEN];

it('should work', () => {
            const mock = sinon.mock(utils);

            process.env[ENV_VARS.LOCAL_STORAGE_DIR] = LOCAL_STORAGE_DIR;

            mock.expects('openLocalStorage').once();
            Apify.openRequestQueue();

            mock.expects('openLocalStorage').once();
            Apify.openRequestQueue('xxx');
            mock.expects('openRemoteStorage').once();
            Apify.openRequestQueue('xxx', { forceCloud: true });

            delete process.env[ENV_VARS.LOCAL_STORAGE_DIR];
            process.env[ENV_VARS.TOKEN] = 'xxx';

            mock.expects('openRemoteStorage').once();
            Apify.openRequestQueue();

            delete process.env[ENV_VARS.TOKEN];

            mock.verify();
            mock.restore();
        });
    });

it('throws if APIFY_DEFAULT_KEY_VALUE_STORE_ID env var is not defined and we use cloud storage', async () => {
            delete process.env[ENV_VARS.LOCAL_STORAGE_DIR];
            delete process.env[ENV_VARS.DEFAULT_KEY_VALUE_STORE_ID];
            process.env[ENV_VARS.TOKEN] = 'xxx';

            const errMsg = 'The \'APIFY_DEFAULT_KEY_VALUE_STORE_ID\' environment variable is not defined';
            await expect(Apify.getValue('KEY')).to.be.rejectedWith(errMsg);

            delete process.env[ENV_VARS.TOKEN];
        });
    });

export const expectNotUsingLocalStorage = () => expect(process.env[ENV_VARS.LOCAL_STORAGE_DIR]).toBeUndefined();

import path from 'path';
import { promisify } from 'util';
import express from 'express';
import socketio from 'socket.io';
import log from 'apify-shared/log';
import { checkParamOrThrow } from 'apify-client/build/utils';
import { promisifyServerListen } from 'apify-shared/utilities';
import { ENV_VARS, LOCAL_ENV_VARS } from 'apify-shared/consts';
import { addTimeoutToPromise } from '../utils';
import Snapshot from './snapshot';

const writeFile = promisify(fs.writeFile);
const unlink = promisify(fs.unlink);
const ensureDir = promisify(fs.ensureDir);

const LOCAL_STORAGE_DIR = process.env[ENV_VARS.LOCAL_STORAGE_DIR] || '';
const DEFAULT_SCREENSHOT_DIR_PATH = path.resolve(LOCAL_STORAGE_DIR, 'live_view');

/**
 * `LiveViewServer` enables serving of browser snapshots via web sockets. It includes its own client
 * that provides a simple frontend to viewing the captured snapshots. A snapshot consists of three
 * pieces of information, the currently opened URL, the content of the page (HTML) and its screenshot.
 *
 * ```json
 * {
 *     "pageUrl": "https://www.example.com",
 *     "htmlContent": " ....",
 *     "screenshotIndex": 3,
 *     "createdAt": "2019-04-18T11:50:40.060Z"
 * }
 * ```
 *

const getLocalStorageDir = () => {
    const envVar = ENV_VARS.LOCAL_STORAGE_DIR;

    return process.env[envVar] || DEFAULT_LOCAL_STORAGE_DIR;
};
const getLocalKeyValueStorePath = (storeId) => {

export const openRequestQueue = (queueIdOrName, options = {}) => {
    checkParamOrThrow(queueIdOrName, 'queueIdOrName', 'Maybe String');
    checkParamOrThrow(options, 'options', 'Object');
    ensureTokenOrLocalStorageEnvExists('request queue');

    const { forceCloud = false } = options;
    checkParamOrThrow(forceCloud, 'options.forceCloud', 'Boolean');

    return process.env[ENV_VARS.LOCAL_STORAGE_DIR] && !forceCloud
        ? openLocalStorage(queueIdOrName, ENV_VARS.DEFAULT_REQUEST_QUEUE_ID, RequestQueueLocal, queuesCache)
        : openRemoteStorage(queueIdOrName, ENV_VARS.DEFAULT_REQUEST_QUEUE_ID, RequestQueue, queuesCache, getOrCreateQueue);
};

export const openKeyValueStore = (storeIdOrName, options = {}) => {
    checkParamOrThrow(storeIdOrName, 'storeIdOrName', 'Maybe String');
    checkParamOrThrow(options, 'options', 'Object');
    ensureTokenOrLocalStorageEnvExists('key value store');

    const { forceCloud = false } = options;
    checkParamOrThrow(forceCloud, 'options.forceCloud', 'Boolean');

    return process.env[ENV_VARS.LOCAL_STORAGE_DIR] && !forceCloud
        ? openLocalStorage(storeIdOrName, ENV_VARS.DEFAULT_KEY_VALUE_STORE_ID, KeyValueStoreLocal, storesCache)
        : openRemoteStorage(storeIdOrName, ENV_VARS.DEFAULT_KEY_VALUE_STORE_ID, KeyValueStore, storesCache, getOrCreateKeyValueStore);
};