Request
const request = new Request(event)
Methods:
request.parameter(key)
// Get URL path paramter, ex: /Users/{username}, request.parameter('username')
request.get(key, defaultValue)
// Get query string, ex: ?filter=hello, request.get('filter', null)
request.input(key, defaultValue)
// Get post field data, ex: name=Josh, request.input('name', 'Who')
request.inputs(keys)
// Get post mulitple fields data, ex: name=Josh&enabled=true, request.inputs(['name', 'enabled'])
request.validate(keysProvider)
// Validate input data, keysProvider is an callback, keysProvider(joi) please return a Joi rules