@toruslabs/broadcast-channel/dist/lib.esm/method-chooser.js

A BroadcastChannel that works in New Browsers, Old Browsers, WebWorkers

import * as indexedDb from './methods/indexed-db.js';
import * as localstorage from './methods/localstorage.js';
import * as native from './methods/native.js';
import * as server from './methods/server.js';
import * as simulate from './methods/simulate.js';

// order is important
const METHODS = [native,
// fastest
indexedDb, localstorage, server];
function chooseMethod(options) {
  let chooseMethods = [].concat(options.methods || [], METHODS).filter(Boolean);

  // directly chosen
  if (options.type) {
    if (options.type === "simulate") {
      // only use simulate-method if directly chosen
      return simulate;
    }
    const ret = chooseMethods.find(m => m.type === options.type);
    if (!ret) throw new Error(`method-type ${options.type} not found`);else return ret;
  }

  /**
   * if no webworker support is needed,
   * remove idb from the list so that localstorage is been chosen
   */
  if (!options.webWorkerSupport) {
    chooseMethods = chooseMethods.filter(m => m.type !== "idb");
  }
  const useMethod = chooseMethods.find(method => method.canBeUsed(options));
  if (!useMethod) throw new Error(`No useable method found in ${JSON.stringify(METHODS.map(m => m.type))}`);else return useMethod;
}

export { chooseMethod };