[browser micro-lib] #JavaScript #browser #growth #frontend

lib.js

https://github.com/terkelg/facon


// in Offirmo monorepo!
function poll(predicate, options) {
  // early check to save an initial poll period
  let result = predicate();
  if (result)
    return Promise.resolve(result);

  const {periodMs, timeoutMs, debugId} = Object.assign({
    periodMs: 100, // check every 100ms
    timeoutMs: 10 * 1000, // after 10 seconds, timeout
    debugId: 'an unnamed predicate',
  }, options || {});

  return new Promise((resolve, reject) => {
    const waitForElement = setInterval(() => {
      result = predicate();
      if (!result) return;

      clearTimeout(waitForTimeout);
      clearInterval(waitForElement);
      resolve(result);
    }, periodMs);

    const waitForTimeout = setTimeout(() => {
      clearInterval(waitForElement);
      reject(new Error(`${EXPERIMENT_ID} Timed out while waiting for "${debugId}"`));
    }, timeoutMs);
  });
}

// in Offirmo monorepo!
function pollWindowVariable(varname, options) {
  options = Object.assign({}, {debugId: `window.${varname}`}, options || {});
  return poll(() => window[varname], options);
}

function pollAngularInjector(angular, options) {
  options = Object.assign({}, {debugId: `AngularJS current app $injector`}, options || {});
  // https://stackoverflow.com/a/13403660/587407
  // https://stackoverflow.com/a/15536532/587407
  return poll(() => angular.element(document.body).injector(), options);
}

function pollAngularModule(injector, name, options) {
  options = Object.assign({}, {debugId: `AngularJS module ${name}`}, options || {});
  return poll(() => injector.has(name), options)
    .then(() => injector.get(name));
}

function pollDOMSelectorPresence(selector, options) {
  options = Object.assign({}, {
    debugId: `DOM selector ${selector}`,
    container: document,
  }, options || {});
  return poll(() => options.container.querySelector(selector), options);
}

// in Offirmo monorepo!
const styleOnce = (css, id, document = window.document) => {
  const styleId = `${EXPERIMENT_ID}-${id.replace(/[./]/g, '-')}`;
  const existingElement = document.getElementById(id);
  if (existingElement)
    return existingElement;

  const style = document.createElement('style');
  style.setAttribute('id', styleId);
  style.innerHTML = css;
  document.head.appendChild(style);
  return style;
}


// XXX deprecated
  const searchParams = new URLSearchParams(window.location.search);
  const userEmail = searchParams.get('userEmail');

// https://github.com/Offirmo/simple-querystring-parser/blob/master/index.js
function lightQuerystringValueDecoder(val) {
  // A bare parameter, is likely to mean true, like ?showUsers
  // WARNING this is a voluntary departure from the standard http://w3.org/TR/2012/WD-url-20120524/#collect-url-parameters
  if (typeof val !== 'string')
    return true

  if (val.match(/^[0-9]+$/))
    return Number(val)

  if (val === 'true')
    return true

  if (val === 'false')
    return false

  return val // no inference
}

function parseQuerystring(querystring, options) {
  options = options || {}
  options.valueDecoder = options.valueDecoder || lightQuerystringValueDecoder
  // Create an object with no prototype https://github.com/sindresorhus/query-string/issues/47
  var result = Object.create(null)

  if (typeof querystring !== 'string')
    return result

  // remove possible leading char, whatever it may be
  querystring = querystring.trim().replace(/^(\?|#|&)/, '');

  if (!querystring)
    return result

  var raw_options = querystring.split('&')
  return raw_options.reduce(function (acc, raw_option) {
    if (!raw_option) return acc

    var split = raw_option.split('=')
    var key = decodeURIComponent(split[0])
    var value = decodeURIComponent(split.slice(1).join('=')) || undefined
    acc[key] = options.valueDecoder(value)
    return acc
  }, result)
}

export default parseQuerystring;

export { lightQuerystringValueDecoder, parseQuerystring };


parseQuerystring(window.location.search)