xenadmin/CFUValidator/Updates/AlternativeUrlDownloadUpdatesXmlSourceAction.cs

/* Copyright (c) Citrix Systems, Inc. 
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using System;
using System.IO;
using System.Net;
using System.Xml;
using XenAdmin.Actions;


namespace CFUValidator.Updates
{
    class AlternativeUrlDownloadUpdatesXmlSourceAction : DownloadUpdatesXmlAction, ICheckForUpdatesXMLSource
    {
        private readonly string _url;

        public AlternativeUrlDownloadUpdatesXmlSourceAction(string url)
            : base(true, true, true, "CFU", true)
        {
            _url = url ?? throw new ArgumentNullException(nameof(url));
        }

        protected override XmlDocument FetchCheckForUpdatesXml()
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                XmlReaderSettings settings = new XmlReaderSettings
                {
                    IgnoreComments = true,
                    IgnoreWhitespace = true,
                    IgnoreProcessingInstructions = true
                };

                WebRequest wr = WebRequest.Create(_url);
                using (Stream xmlStream = wr.GetResponse().GetResponseStream())
                {
                    if (xmlStream != null)
                        using (var reader = XmlReader.Create(xmlStream, settings))
                            doc.Load(reader);
                }

                return doc;
            }
            catch (Exception)
            {
                ErrorRaised = new CFUValidationException("Failed to wget the URL: " + _url);
                throw ErrorRaised;
            }
        }

        public Exception ErrorRaised { get; private set; }
    }
}