MetaWeblog.cs :  » RSS-RDF » RSS-Feeder » RSSBlogAPI » C# / CSharp Open Source

// Copyright  2005 by Omar Al Zabir. All rights are reserved.
// 
// If you like this code then feel free to go ahead and use it.
// The only thing I ask is that you don't remove or alter my copyright notice.
//
// Your use of this software is entirely at your own risk. I make no claims or
// warrantees about the reliability or fitness of this code for any particular purpose.
// If you make changes or additions to this code please mark your code as being yours.
// 
// website http://www.oazabir.com, email OmarAlZabir@gmail.com, msn oazabir@hotmail.com
using System;
using System.IO;
using System.Text;
using System.Xml;
using System.Web;
using System.Net;
using System.Net.Sockets;
using System.Diagnostics;
using System.Xml.XPath;
using System.Collections;
using System.Security.Cryptography;
using System.Configuration;

namespace RSSBlogAPI{
  /// <summary>
  /// Metaweblog API for WordPress and B2Evolution
  /// </summary>
  public class MetaWeblog : BlogAPIBase
  {
    private WebLog _WebLog;

    private readonly string _GetCategoriesMethodName;
    private readonly string _PostMethodName;
    private readonly string _DateTimeFieldType;

    public MetaWeblog( WebLog log )
    {
      this._WebLog = log;

      // Different blog engines have different method names
      if( log.Engine == EngineEnum.B2Evolution )
      {
        _GetCategoriesMethodName = "b2.getCategories";
        _PostMethodName = "b2.newPost";
      }
      else
      {
        _GetCategoriesMethodName = "metaWeblog.getCategories";
        _PostMethodName = "metaWeblog.newPost";
      }

      _DateTimeFieldType = "dateTime.iso8601";
    }
    public override bool HasCategories
    {
      get { return true; }
    }

    public override bool HasBlogId
    {
      get { return true; }
    }
    public override string EngineName
    {
      get { return "MetaWebLog (Movable type, dasBlog, wordpress)"; }
    }

    public override string HelpText
    {
      get { return "Movable type, dasBlog, wordpress"; }
    }

    
    public override void Test()
    {
      this.GetCategories();
    }

    /// <summary>
    /// Get categories from the blog engine.
    /// </summary>
    /// <returns></returns>
    public override Category [] GetCategories()
    {
      HttpWebRequest request = CreateRequest( "POST" );

      byte [] xml = BuildXmlRpc( this._GetCategoriesMethodName, this.BlogId, this.Username, this.Password );
      request.ContentLength = xml.Length;

      using( Stream requestStream = request.GetRequestStream())
        requestStream.Write( xml, 0, xml.Length );

      using( HttpWebResponse response = request.GetResponse() as HttpWebResponse )
      {
        if ( response.StatusCode != HttpStatusCode.OK )
          throw new ApplicationException( response.StatusDescription );

        using( Stream responseStream = response.GetResponseStream() )
          using( StreamReader reader = new StreamReader( responseStream, RSSCommon.Constants.DefaultEncoding ) )
            return DeserializeCategoriesXml( reader );
      }
    }

    /// <summary>
    /// Post to weblog
    /// </summary>
    /// <param name="post"></param>
    /// <returns></returns>
    public override string PostItem( Post post )
    {
      HttpWebRequest request = CreateRequest( "POST" );

      byte [] xml;
      if( EngineEnum.B2Evolution ==  this._WebLog.Engine )
      {
        // B2 Supports special format
        xml = BuildXmlRpc( this._PostMethodName, 
          this.BlogId, string.Empty,
          this.Username, this.Password, 
          post.Text, true, post.Title, (post.Categories.Length > 0 ? post.Categories[0].Id.ToString() : "0"), 
          post.Date.ToString( "yyyy-MM-dd hh:mm:sszzz" ) );
      }
      else
      {
        xml = BuildXmlRpc( this._PostMethodName, this.BlogId, 
          this.Username, this.Password, post, true );
      }

      request.ContentLength = xml.Length;

      using( Stream requestStream = request.GetRequestStream())
        requestStream.Write( xml, 0, xml.Length );

      using( HttpWebResponse response = request.GetResponse() as HttpWebResponse )
      {
        if ( response.StatusCode != HttpStatusCode.OK )
          throw new ApplicationException( response.StatusDescription );

        using( Stream responseStream = response.GetResponseStream() )
          using( StreamReader reader = new StreamReader( responseStream, Encoding.UTF8 ) )
            return DeserializePostXml( reader );
      }
    }

    private Category [] DeserializeCategoriesXml( StreamReader reader )
    {
      ArrayList list = new ArrayList();

      XPathDocument xDoc = new XPathDocument( reader );
      XPathNavigator navigator = xDoc.CreateNavigator();

      XPathNodeIterator fault = navigator.Select( "/methodResponse/fault/value" );

      if ( fault.Count == 0 )
      {
        XPathNodeIterator values = navigator.Select( "/methodResponse/params/param/value/array/data/value" );

        while( values.MoveNext() )
        {
          Category category = GetCategory( values.Current );

          if ( category != null )
            list.Add( category );
        }

        return list.ToArray( typeof( Category ) ) as Category [];
      }
      else
      {
        fault.MoveNext();
        throw new ApplicationException("Invalid content in XML: " + fault.Current.Value);
      }
    }

    private string DeserializePostXml( StreamReader reader )
    {
      ArrayList list = new ArrayList();

#if(DEBUG)
      string response = reader.ReadToEnd();
      Debug.WriteLine( response );
      XPathDocument xDoc = new XPathDocument( new StringReader( response ) );
#else
      XPathDocument xDoc = new XPathDocument( reader );
#endif
      
      XPathNavigator navigator = xDoc.CreateNavigator();

      XPathNodeIterator fault = navigator.Select( "/methodResponse/fault/value" );

      if ( fault.Count != 0 )
      {
        fault.MoveNext();
        throw new ApplicationException( GetFault( fault.Current ) );
      }
      else
      {
        XPathNodeIterator postID = navigator.Select( "/methodResponse/params/param/value/string" );
        if( postID.Count != 0 )
        {
          return postID.Current.Value;
        }
        else
        {
          return string.Empty;
        }
      }
    }

    private Category GetCategory( XPathNavigator navigator )
    {
      Category category = new Category();

      XPathNodeIterator members = navigator.Select( "struct/member" );

      while( members.MoveNext() )
      {
        string memberName = ( string )members.Current.Evaluate( "string(name/text())" );
        string memberValue = ( string )members.Current.Evaluate( "string(value/string/text())" );

        if ( memberName.ToLower() == "categoryid" )
          category.Id = memberValue;
        else if ( memberName.ToLower() == "title" || 
              memberName.ToLower() == "categoryname" )
          category.Title = memberValue;
      }

      return ( category.Title != string.Empty && category.Id != string.Empty ) ? category : null;
    }

    private string GetFault( XPathNavigator navigator )
    {
      XPathNodeIterator members = navigator.Select( "struct/member" );

      while( members.MoveNext() )
      {
        string memberName = ( string )members.Current.Evaluate( "string(name/text())" );
        string memberValue = ( string )members.Current.Evaluate( "string(value/string/text())" );
        if ( memberName.ToLower() == "faultstring" )
          return memberValue;
      }

      return string.Empty;
    }

    private byte [] BuildXmlRpc( string method, params object [] args )
    {
      using( MemoryStream mStream = new MemoryStream() )
      {
        XmlTextWriter xWriter = new XmlTextWriter( mStream, Encoding.UTF8 );

        xWriter.Indentation = 1;
        xWriter.Formatting = Formatting.Indented;
        xWriter.IndentChar = '\t';
        xWriter.QuoteChar = '"';

        xWriter.WriteStartDocument();
        xWriter.WriteStartElement( "methodCall" );
        xWriter.WriteElementString( "methodName", method );

        xWriter.WriteStartElement( "params" );

        foreach( object param in args )
        {
          xWriter.WriteStartElement( "param" );
          xWriter.WriteStartElement( "value" );

          if ( param is string )
            xWriter.WriteElementString( "string", param.ToString() );
          else if ( param is bool )
            xWriter.WriteElementString( "boolean", ( ( bool ) param ) ? "1" : "0" );
          else if( param is DateTime )
            xWriter.WriteElementString( _DateTimeFieldType, ((DateTime)param).ToString( "yyyyMMddThh:mm:sszzz" ) );
          else if ( param is Post )
          {
            xWriter.WriteStartElement( "struct" );
            WritePost( xWriter, ( Post )param );
            xWriter.WriteEndElement();
          }
                    
          xWriter.WriteEndElement();
          xWriter.WriteEndElement();
        }

        xWriter.WriteEndElement();
        xWriter.WriteEndElement();

        xWriter.Flush();

        return mStream.ToArray();
      }
    }

    private void WritePost( XmlTextWriter xWriter, Post post )
    {
      // This format is for Word Press
      string date = post.Date.ToString( "yyyyMMddThh:mm:sszzz" );
      //string date = "20050701T09:18:58Z";

      WriteMember( xWriter, _DateTimeFieldType, "dateCreated", date );
      //WriteMember( xWriter, "dateTime", "dateCreated", date );
      //WriteMember( xWriter, "dateTime.iso8601", "dateCreated", date );
      WriteMember( xWriter, "string", "description", post.Text );
      WriteMember( xWriter, "string", "title", post.Title );
      WriteCategories( xWriter, "categories", post.Categories );
      WriteMember( xWriter, "string", "link", string.Empty );
      WriteMember( xWriter, "string", "permalink", string.Empty );
      WriteMember( xWriter, "string", "postid", string.Empty );
    }

    private void WriteMember( XmlTextWriter xWriter, string type, string name, string val )
    {
      xWriter.WriteStartElement( "member" );
      xWriter.WriteElementString( "name", name );
      xWriter.WriteStartElement( "value" );
      xWriter.WriteElementString( type, val );
      xWriter.WriteEndElement();
      xWriter.WriteEndElement();
    }

    private void WriteCategories( XmlTextWriter xWriter, string name, Category [] val )
    {
      xWriter.WriteStartElement( "member" );
      xWriter.WriteElementString( "name", "categories" );
      xWriter.WriteStartElement( "value" );
      xWriter.WriteStartElement( "array" );
      xWriter.WriteStartElement( "data" );

      foreach( Category cat in val )
      {
        xWriter.WriteStartElement( "value" );
        xWriter.WriteElementString( "string", cat.Title );
        xWriter.WriteEndElement();
      }

      xWriter.WriteEndElement();
      xWriter.WriteEndElement();
      xWriter.WriteEndElement();
      xWriter.WriteEndElement();
    }
  }
}