@dwp/govuk-casa/lib/utils/createGetRequest.js

Framework for creating basic GOVUK Collect-And-Submit-Applications

const { DEFAULT_CONTEXT_ID } = require('../enums.js');
const { sanitiseWaypoint, sanitiseRelativeUrl, sanitiseContextId } = require('./sanitise.js');
const { validateMountUrl, validateWaypoint } = require('./validate.js');

/**
 * Create a URL for use in GET requests, or links.
 *
 * If neither a waypoint or mountUrl is provided, only the query portion of the
 * URL will be returned. This is a convenience for situation where you just want
 * to append a query to an existing URL without regenerating the query each time.
 *
 * @param {object} requestObject Request object
 * @returns {string} URL
 */
module.exports = function createGetRequest(requestObject = {}) {
  const {
    waypoint,
    editMode,
    editOrigin,
    contextId,
    skipTo,
    mountUrl,
  } = requestObject;

  // Mount URL
  let urlPath = '';
  if (mountUrl !== undefined) {
    validateMountUrl(mountUrl);
    urlPath = mountUrl;
  }

  // Waypoint
  if (waypoint !== undefined) {
    validateWaypoint(waypoint, { withOrigin: true });
    urlPath = `${urlPath}${sanitiseWaypoint(waypoint)}`;
  }
  const url = new URL(urlPath, 'https://base.test');

  // Edit mode and origin
  if (editMode === true) {
    url.searchParams.set('edit', '');
    if (editOrigin) {
      url.searchParams.set('editorigin', sanitiseRelativeUrl(editOrigin));
    }
  }

  // Context ID
  if (contextId && contextId !== DEFAULT_CONTEXT_ID) {
    url.searchParams.set('contextid', sanitiseContextId(contextId));
  }

  // Skip reference
  if (skipTo) {
    url.searchParams.set('skipto', sanitiseWaypoint(skipTo));
  }

  // Return path / querystring
  return !waypoint && !mountUrl ? url.search : `${url.pathname}${url.search}`;
};