private void OnElementElementCompleted(RssElement e)
{
ElementsChanged?.Invoke(e, EventArgs.Empty);
if (Elements.Where(r => r.Completed == false).FirstOrDefault() == null)
{
LoadCompleted?.Invoke(this, EventArgs.Empty);
}
}
private async Task Fetch(Category category)
{
var rssElement = new RssElement
{
Category = category,
EndPoint = new Uri(string.Format(ARTICLE_URI, category.Id))
};
try
{
var xmlDocument = await XmlDocument.LoadFromUriAsync(rssElement.EndPoint);
var channelNode = xmlDocument.LastChild?.SelectSingleNode("channel");
if (channelNode != null)
{
rssElement.Category.Title = channelNode.SelectSingleNode("title")?.InnerText;
rssElement.Category.Copyright = channelNode.SelectSingleNode("copyright")?.InnerText;
rssElement.Category.Language = channelNode.SelectSingleNode("language")?.InnerText;
rssElement.Category.Description = channelNode.SelectSingleNode("description")?.InnerText;
rssElement.Category.Link = new Uri(channelNode.SelectSingleNode("link")?.InnerText);
rssElement.Articles = new List <Article>();
foreach (var item in channelNode.SelectNodes("item"))
{
var article = new Article
{
Category = rssElement.Category,
Title = item.SelectSingleNode("title")?.InnerText,
Description = item.SelectSingleNode("description")?.InnerText,
Link = new Uri(item.SelectSingleNode("link")?.InnerText),
PubDate = DateTime.Parse(item.SelectSingleNode("pubDate")?.InnerText)
};
article.Id = int.Parse(article.Link.ToString().Replace(ID_PATTERN, string.Empty).Split('-').First());
rssElement.Articles.Add(article);
if (!Articles.Any(a => a.Link.Equals(article.Link)))
{
Articles.Add(article);
}
}
_elements.Add(rssElement);
}
}
catch (Exception exception)
{
Debug.WriteLine(exception.Message);
}
}
private async void Load(Uri uri, Category c)
{
RssElement e = new RssElement()
{
Category = c,
EndPoint = uri
};
Elements.Add(e);
await e.Fetch();
e.Completed = true;
OnElementElementCompleted(e);
}
public void Display(string url)
{
if (string.IsNullOrEmpty(url))
{
throw new ArgumentException("Null RssFeedUrl");
}
RssFeed feed = null;
if (HttpContext.Current.Cache.Get(RSS_CACHE_NAME) == null)
{
feed = RssFeed.Read(url);
HttpContext.Current.Cache.Add(RSS_CACHE_NAME, feed, null, DateTime.Now.AddDays(1),
TimeSpan.Zero, System.Web.Caching.CacheItemPriority.Default, null);
}
else
{
feed = HttpContext.Current.Cache.Get(RSS_CACHE_NAME) as RssFeed;
}
// Limit feed to the first 4 elements:
if ((feed.Channels != null) && (feed.Channels.Count > 0))
{
for (int i = feed.Channels.Count - 1; i > 3; --i)
{
feed.Channels.RemoveAt(i);
}
RssItemCollection items = feed.Channels[0].Items;
if ((items != null) && (items.Count > 0))
{
for (int i = items.Count - 1; i > 3; --i)
{
RssElement element = items[i];
items.RemoveAt(i);
}
}
}
listChannels.DataSource = feed.Channels;
listChannels.DataBind();
}
private static RssFeed read(string url, HttpWebRequest request, RssFeed oldFeed)
{
// ***** Marked for substantial improvement
RssFeed feed = new RssFeed();
Stream stream = null;
Uri uri = new Uri(url);
feed.url = url;
switch (uri.Scheme)
{
case "file":
feed.lastModified = File.GetLastWriteTime(url);
if ((oldFeed != null) && (feed.LastModified == oldFeed.LastModified))
{
oldFeed.cached = true;
return(oldFeed);
}
stream = new FileStream(url, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
break;
case "https":
case "http":
if (request == null)
{
request = (HttpWebRequest)WebRequest.Create(uri);
request.Proxy = WebProxy.GetDefaultProxy();
request.Proxy.Credentials = CredentialCache.DefaultCredentials;
}
if (oldFeed != null)
{
request.IfModifiedSince = oldFeed.LastModified;
request.Headers.Add("If-None-Match", oldFeed.ETag);
}
try
{
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
feed.lastModified = response.LastModified;
feed.etag = response.Headers["ETag"];
try
{
if (response.ContentEncoding != String.Empty)
{
feed.encoding = Encoding.GetEncoding(response.ContentEncoding);
}
}
catch
{
}
stream = response.GetResponseStream();
}
catch (WebException we)
{
if (oldFeed != null)
{
oldFeed.cached = true;
return(oldFeed);
}
throw we; // bad
}
break;
}
if (stream != null)
{
RssReader reader = null;
try
{
reader = new RssReader(stream);
RssElement element = null;
do
{
element = reader.Read();
if (element is RssChannel.RssChannel)
{
feed.Channels.Add((RssChannel.RssChannel)element);
}
} while (element != null);
feed.rssVersion = reader.Version;
}
finally
{
feed.exceptions = reader.Exceptions;
reader.Close();
}
}
else
{
throw new ApplicationException("Not a valid Url");
}
return(feed);
}
/// <summary>
/// Reads the next RssElement from the stream.
/// </summary>
/// <returns> An RSS Element </returns>
/// <exception cref="InvalidOperationException">RssReader has been closed, and can not be read.</exception>
/// <exception cref="System.IO.FileNotFoundException">RSS file not found.</exception>
/// <exception cref="System.Xml.XmlException">Invalid XML syntax in RSS file.</exception>
/// <exception cref="System.IO.EndOfStreamException">Unable to read an RssElement. Reached the end of the stream.</exception>
public RssElement Read()
{
bool readData = false;
RssElement rssElement = null;
int lineNumber = -1;
int linePosition = -1;
if (this.reader == null)
{
throw new InvalidOperationException("RssReader has been closed, and can not be read.");
}
do
{
bool pushElement = true;
try
{
readData = this.reader.Read();
}
catch (EndOfStreamException e)
{
throw new EndOfStreamException("Unable to read an RssElement. Reached the end of the stream.", e);
}
catch (XmlException e)
{
if (lineNumber != -1 || linePosition != -1)
{
if (this.reader.LineNumber == lineNumber && this.reader.LinePosition == linePosition)
{
throw this.exceptions.LastException;
}
}
lineNumber = this.reader.LineNumber;
linePosition = this.reader.LinePosition;
this.exceptions.Add(e); // just add to list of exceptions and continue :)
}
if (readData)
{
string readerName = this.reader.Name.ToLower();
switch (this.reader.NodeType)
{
case XmlNodeType.Element:
{
//if (reader.IsEmptyElement)
// break;
// doesnt take empty elements into account :/
this.elementText = new StringBuilder();
switch (readerName)
{
case "item":
// is this the end of the channel element? (absence of </channel> before <item>)
if (!this.wroteChannel)
{
this.wroteChannel = true;
rssElement = this.channel; // return RssChannel
readData = false;
}
this.item = new RssItem.RssItem(); // create new RssItem
this.channel.Items.Add(this.item);
break;
case "source":
this.source = new RssSource();
this.item.Source = this.source;
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
switch (this.reader.Name.ToLower())
{
case "url":
try
{
this.source.Url = new Uri(this.reader.Value);
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
}
}
break;
case "enclosure":
this.enclosure = new RssEnclosure();
this.item.Enclosure = this.enclosure;
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
switch (this.reader.Name.ToLower())
{
case "url":
try
{
this.enclosure.Url = new Uri(this.reader.Value);
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "length":
try
{
this.enclosure.Length = int.Parse(this.reader.Value);
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "type":
this.enclosure.Type = this.reader.Value;
break;
}
}
break;
case "guid":
this.guid = new RssGuid();
this.item.Guid = this.guid;
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
switch (this.reader.Name.ToLower())
{
case "ispermalink":
try
{
this.guid.PermaLink = bool.Parse(this.reader.Value);
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
}
}
break;
case "category":
this.category = new RssCategory();
if ((string)this.xmlNodeStack.Peek() == "channel")
{
this.channel.Categories.Add(this.category);
}
else
{
this.item.Categories.Add(this.category);
}
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
switch (this.reader.Name.ToLower())
{
case "url":
goto case "domain";
case "domain":
this.category.Domain = this.reader.Value;
break;
}
}
break;
case "channel":
this.channel = new RssChannel.RssChannel();
this.textInput = null;
this.image = null;
this.cloud = null;
this.source = null;
this.enclosure = null;
this.category = null;
this.item = null;
break;
case "image":
this.image = new RssImage();
this.channel.Image = this.image;
break;
case "textinput":
this.textInput = new RssTextInput();
this.channel.TextInput = this.textInput;
break;
case "cloud":
pushElement = false;
this.cloud = new RssCloud();
this.channel.Cloud = this.cloud;
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
switch (this.reader.Name.ToLower())
{
case "domain":
this.cloud.Domain = this.reader.Value;
break;
case "port":
try
{
this.cloud.Port = ushort.Parse(this.reader.Value);
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "path":
this.cloud.Path = this.reader.Value;
break;
case "registerprocedure":
this.cloud.RegisterProcedure = this.reader.Value;
break;
case "protocol":
switch (this.reader.Value.ToLower())
{
case "xml-rpc":
this.cloud.Protocol = RssCloudProtocol.XmlRpc;
break;
case "soap":
this.cloud.Protocol = RssCloudProtocol.Soap;
break;
case "http-post":
this.cloud.Protocol = RssCloudProtocol.HttpPost;
break;
default:
this.cloud.Protocol = RssCloudProtocol.Empty;
break;
}
break;
}
}
break;
case "rss":
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
if (this.reader.Name.ToLower() == "version")
{
switch (this.reader.Value)
{
case "0.91":
this.rssVersion = RssVersion.RSS091;
break;
case "0.92":
this.rssVersion = RssVersion.RSS092;
break;
case "2.0":
this.rssVersion = RssVersion.RSS20;
break;
default:
this.rssVersion = RssVersion.NotSupported;
break;
}
}
}
break;
case "rdf":
for (int i = 0; i < this.reader.AttributeCount; i++)
{
this.reader.MoveToAttribute(i);
if (this.reader.Name.ToLower() == "version")
{
switch (this.reader.Value)
{
case "0.90":
this.rssVersion = RssVersion.RSS090;
break;
case "1.0":
this.rssVersion = RssVersion.RSS10;
break;
default:
this.rssVersion = RssVersion.NotSupported;
break;
}
}
}
break;
}
if (pushElement)
{
this.xmlNodeStack.Push(readerName);
}
break;
}
case XmlNodeType.EndElement:
{
if (this.xmlNodeStack.Count == 1)
{
break;
}
string childElementName = (string)this.xmlNodeStack.Pop();
string parentElementName = (string)this.xmlNodeStack.Peek();
switch (childElementName) // current element
{
// item classes
case "item":
rssElement = this.item;
readData = false;
break;
case "source":
this.source.Name = this.elementText.ToString();
rssElement = this.source;
readData = false;
break;
case "enclosure":
rssElement = this.enclosure;
readData = false;
break;
case "guid":
this.guid.Name = this.elementText.ToString();
rssElement = this.guid;
readData = false;
break;
case "category": // parent is either item or channel
this.category.Name = this.elementText.ToString();
rssElement = this.category;
readData = false;
break;
// channel classes
case "channel":
if (this.wroteChannel)
{
this.wroteChannel = false;
}
else
{
this.wroteChannel = true;
rssElement = this.channel;
readData = false;
}
break;
case "textinput":
rssElement = this.textInput;
readData = false;
break;
case "image":
rssElement = this.image;
readData = false;
break;
case "cloud":
rssElement = this.cloud;
readData = false;
break;
}
switch (parentElementName) // parent element
{
case "item":
switch (childElementName)
{
case "title":
this.item.Title = this.elementText.ToString();
break;
case "link":
this.item.Link = new Uri(this.elementText.ToString());
break;
case "description":
this.item.Description = this.elementText.ToString();
break;
case "author":
this.item.Author = this.elementText.ToString();
break;
case "comments":
this.item.Comments = this.elementText.ToString();
break;
case "pubdate":
try
{
this.item.PubDate = DateTime.Parse(this.elementText.ToString());
}
catch (Exception e)
{
try
{
string tmp = this.elementText.ToString();
tmp = tmp.Substring(0, tmp.Length - 5);
tmp += "GMT";
this.item.PubDate = DateTime.Parse(tmp);
}
catch
{
this.exceptions.Add(e);
}
}
break;
}
break;
case "channel":
switch (childElementName)
{
case "title":
this.channel.Title = this.elementText.ToString();
break;
case "link":
try
{
this.channel.Link = new Uri(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "description":
this.channel.Description = this.elementText.ToString();
break;
case "language":
this.channel.Language = this.elementText.ToString();
break;
case "copyright":
this.channel.Copyright = this.elementText.ToString();
break;
case "managingeditor":
this.channel.ManagingEditor = this.elementText.ToString();
break;
case "webmaster":
this.channel.WebMaster = this.elementText.ToString();
break;
case "rating":
this.channel.Rating = this.elementText.ToString();
break;
case "pubdate":
try
{
this.channel.PubDate = DateTime.Parse(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "lastbuilddate":
try
{
this.channel.LastBuildDate =
DateTime.Parse(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "generator":
this.channel.Generator = this.elementText.ToString();
break;
case "docs":
this.channel.Docs = this.elementText.ToString();
break;
case "ttl":
try
{
this.channel.TimeToLive = int.Parse(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
}
break;
case "image":
switch (childElementName)
{
case "url":
try
{
this.image.Url = new Uri(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "title":
this.image.Title = this.elementText.ToString();
break;
case "link":
try
{
this.image.Link = new Uri(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "description":
this.image.Description = this.elementText.ToString();
break;
case "width":
try
{
this.image.Width = Byte.Parse(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
case "height":
try
{
this.image.Height = Byte.Parse(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
}
break;
case "textinput":
switch (childElementName)
{
case "title":
this.textInput.Title = this.elementText.ToString();
break;
case "description":
this.textInput.Description = this.elementText.ToString();
break;
case "name":
this.textInput.Name = this.elementText.ToString();
break;
case "link":
try
{
this.textInput.Link = new Uri(this.elementText.ToString());
}
catch (Exception e)
{
this.exceptions.Add(e);
}
break;
}
break;
case "skipdays":
if (childElementName == "day")
{
switch (this.elementText.ToString().ToLower())
{
case "monday":
this.channel.SkipDays[0] = true;
break;
case "tuesday":
this.channel.SkipDays[1] = true;
break;
case "wednesday":
this.channel.SkipDays[2] = true;
break;
case "thursday":
this.channel.SkipDays[3] = true;
break;
case "friday":
this.channel.SkipDays[4] = true;
break;
case "saturday":
this.channel.SkipDays[5] = true;
break;
case "sunday":
this.channel.SkipDays[6] = true;
break;
}
}
break;
case "skiphours":
if (childElementName == "hour")
{
this.channel.SkipHours[Byte.Parse(this.elementText.ToString().ToLower())] =
true;
}
break;
}
break;
}
case XmlNodeType.Text:
this.elementText.Append(this.reader.Value);
break;
case XmlNodeType.CDATA:
this.elementText.Append(this.reader.Value);
break;
}
}
} while (readData);
return(rssElement);
}
