ctx is a context between a Request and a Response.
The number of the parents of the request.
Contains the Request's HTTP headers.
The Unique identifier of the request.
The HTTP method of the request
The proxy address that handles the request
The character encoding of the response body. Leave it blank to allow automatic character encoding of the response body. It is empty by default and it can be set in onRequest callback.
URL of the HTTP request.
The representation of a HTTP request