/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

interface nsIRequest;

/**
 * nsIRequestObserver
 */
[scriptable, uuid(fd91e2e0-1481-11d3-9333-00104ba0fd40)]
interface nsIRequestObserver : nsISupports
{
    /**
     * Called to signify the beginning of an asynchronous request.
     *
     * @param aRequest request being observed
     * @param aContext user defined context
     *
     * An exception thrown from onStartRequest has the side-effect of
     * causing the request to be canceled.
     */
    void onStartRequest(in nsIRequest aRequest,
                        in nsISupports aContext);

    /**
     * Called to signify the end of an asynchronous request.  This
     * call is always preceded by a call to onStartRequest.
     *
     * @param aRequest request being observed
     * @param aContext user defined context
     * @param aStatusCode reason for stopping (NS_OK if completed successfully)
     *
     * An exception thrown from onStopRequest is generally ignored.
     */
    void onStopRequest(in nsIRequest aRequest,
                       in nsISupports aContext,
                       in nsresult aStatusCode);
};