Function normalizeHttpHeaders

core/src/core-plugins.ts:306–314

(headers: HttpHeaders = {})

 * @param headers The HttpHeaders object to normalize
 */
const normalizeHttpHeaders = (headers: HttpHeaders = {}): HttpHeaders => {
  const originalKeys = Object.keys(headers);
  const loweredKeys = Object.keys(headers).map((k) => k.toLocaleLowerCase());
  const normalized = loweredKeys.reduce<HttpHeaders>((acc, key, index) => {
    acc[key] = headers[originalKeys[index]];
    return acc;
  }, {});
  return normalized;
};

/**
 * Builds a string of url parameters that