Source Code for Blog Digest for C#: BlogDigest.cs in Java

Drawing QR-Code in Java Source Code for Blog Digest for C#: BlogDigest.cs

using using using using using using using System; System.Xml; System.Text; System.Net; System.Collections; BlogApps_05; System.Web.Mail;

namespace BlogApps_15 { public class BlogDigest { string username; string password; string to_address; string from_address; string smtp_server; IList subs = new ArrayList(); string auth_key = "http://schemas.microsoft.com /cdo/configuration/smtpauthenticate"; string username_key = "http://schemas.microsoft.com/cdo/configuration/sendusername"; string password_key = "http://schemas.microsoft.com/cdo/configuration/sendpassword";

static void Main(string[] args) { BlogDigest blogDigest = new BlogDigest(); blogDigest.InitFromXml(); blogDigest.run(); } public void run() { System.Console.WriteLine("BlogDigest for C#"); IFeedParser feedParser = new AnyFeedParser(); DateTime since = DateTime.Now.AddDays(-5.0); StringBuilder sb = new StringBuilder(); foreach (string sub in subs) {

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HttpWebRequest request = (HttpWebRequest)WebRequest.Create(sub); request.IfModifiedSince = since;

try { HttpWebResponse response = (HttpWebResponse)request.GetResponse(); IDictionary feedMap = feedParser.ParseFeed(response.GetResponseStream());

sb.Append("-----------------------------\n");

sb.Append("Blog: "); sb.Append(feedMap["title"]); sb.Append("\n\n"); IList itemsList = (IList)feedMap["items"]; foreach (IDictionary itemMap in itemsList) { DateTime pubDate = (DateTime)itemMap["pubDate"]; if (itemMap["pubDate"] == null) { pubDate = (DateTime)itemMap["dc:date"]; } if (pubDate > since) { string title = (string)itemMap["title"]; string content = (string)itemMap["description"]; if (content == null) { content = (string)itemMap["content:encoded"]; } sb.Append("Title: "); sb.Append((String)itemMap["title"]); sb.Append("\n"); sb.Append(itemMap["link"]); sb.Append("\n\n"); } }

} catch (WebException e) { HttpWebResponse res = (HttpWebResponse)e.Response; if (res != null) { if (res.StatusCode == HttpStatusCode.NotModified) { System.Console.WriteLine("Not modified: "+sub); } } else { System.Console.WriteLine( "ERROR: connecting to destination server "); System.Console.WriteLine(e.Message); System.Console.WriteLine(e.StackTrace); } }

} string text = sb.ToString(); if (text.Length > 0) { try { MailMessage Message = new MailMessage(); Message.To = to_address; Message.From = from_address; Message.Subject = "Daily Blog Digest"; Message.Body = text; Message.Fields.Add(auth_key, "1"); if (username != null && password != null) { Message.Fields.Add(username_key, username); Message.Fields.Add(password_key, password); }

The code for Blog Digest for C#

SmtpMail.SmtpServer = smtp_server; SmtpMail.Send(Message);

} catch(Exception ex) { Console.WriteLine("ERROR: " + ex.ToString() ); while( ex.InnerException != null ) { Console.WriteLine( "ERROR" + ex.InnerException.ToString() ); ex = ex.InnerException; } }

} } private void InitFromXml() { // . . . } } }

BlogDigest.cs starts with the familiar preamble of using statements. We include the BlogApps_05 namespace b so that we can use the AnyFeedParser class, and we include the System.Web.Mail namespace C so that we can use .NET s built-in support for sending mail via SMTP protocol. Just inside the BlogDigest class D, we define fields for each of the parameters we will read from the configuration file. We use a list to hold the newsfeed URL strings E. We also include keys that we ll use later for setting email connection authentication F, username G, and password H. In the main method of the class, we create an instance of the class called the InitFromXml() method to read the configuration file I and then we use the run() method to start processing. In the run() method, we first create an instance of the AnyFeedParser class J and create a DateTime object set to one day in the past 1) . Next, we create a StringBuilder, which we ll use to build the digest email message. 1! Using a foreach loop 1@ , we iterate through each of the subscriptions specified in the configuration file. In the loop, we create an HttpWebRequest to fetch the subscription s newsfeed 1# and then set the IfModifiedSince property to perform an HTTP conditional GET. Next, inside a try block, we attempt to get the response from the web server 1$. If the newsfeed has not been modified since the since date, the call to request.getResponse() will throw an exception. If that happens, we ll move on to process the next subscription. If we get a response, we hand the response stream to the feed parser 1%.

Once we have parsed a newsfeed, we add a header to the email message with the newsfeed s title 1^ and loop through the items in the newsfeed 1&. For each item in the newsfeed, we get the publication date 1* . If we don t find it under the key pubDate 1( , we look for a Dublin Core date using the key dc:date. If the item s date is more recent than the since date 2), we add the item s title 2! and link 2@ to the email message. Still inside the foreach loop, we have a catch block to catch any web exceptions that occur during the processing of one subscription. If the response status code is HTTP_NOT_MODIFIED 2# , we print out a Not Modified message and proceed to the next feed. Otherwise, we print out the exception 2$ and continue with the next subscription. Once we finish processing subscriptions and we re out of the foreach loop, we convert the StringBuilder to a string 2%. If that string is not empty, we create a mail message 2^ and set its to 2& and from 2* fields based on configuration parameters. We set the text of the message 2( using the email message we built. If the configuration specified a mail server username and password 3) , we set those fields in the message too. Finally, we send the message on its way 3! . Note that we set up and send the message in a try-catch block, and we take special care to print out any exceptions that are thrown 3@ . The .NET System. Web.Mail classes do not have the best exception handling, and sometimes the only way to debug problems with them is to examine the inner exceptions.