cucumber20.js

function isValidInterface (input, model) {
  return Array.isArray(input)
    ? input.every(element => isObjectValidInterface(element, model))
    : isObjectValidInterface(input, model)
}

function isObjectValidInterface (input, model) {
  return Object.keys(input).every(checkTypeWith(input, model))
}

function checkTypeWith (input, model) {
  return key => {
    const expectedType = model[key]
    return /^array$/.test(expectedType)
      ? Array.isArray(input[key])
      : typeof input[key] === model[key]
  }
}