public void DoTest() { Diagnostics.CassandraTraceSwitch.Level = TraceLevel.Verbose; CassandraLogWriter LogWriter = new CassandraLogWriter(); twtl = new TextWriterTraceListener(LogWriter); Trace.Listeners.Add(twtl); Console.WriteLine("Connecting, setting keyspace and creating Tables.."); Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en-US"); LogWriter.GetContext(new CassandraLogContext(Session)); TwitterContext twitterContext = new TwitterContext(Session); var TweetsTable = twitterContext.GetTable<Tweet>(); var AuthorsTable = twitterContext.GetTable<Author>(); var FollowedTweetsTable = twitterContext.GetTable<FollowedTweet>(); var StatisticsTable = twitterContext.GetTable<Statistics>(); Console.WriteLine("Done!"); //Adding authors and their followers to the Authors table: Console.WriteLine("Adding authors and their followers to the Authors table.."); int AuthorsNo = 10; List<Author> authorsLocal = new List<Author>(); List<Statistics> statisticsLocal = new List<Statistics>(); List<string> authorsID = new List<string>(); for (int i = 0; i < AuthorsNo; i++) { var author_ID = "Author" + i.ToString(); var authorEnt = new Author() { author_id = author_ID, followers = authorsID.Where(aut => aut != author_ID).ToList() }; AuthorsTable.AddNew(authorEnt); AuthorsTable.EnableQueryTracing(authorEnt); authorsLocal.Add(authorEnt); authorsID.Add(authorEnt.author_id); //We will also add current author to the Statistics table: var statEnt = new Statistics() { author_id = author_ID }; StatisticsTable.Attach(statEnt, EntityUpdateMode.ModifiedOnly, EntityTrackingMode.KeepAttachedAfterSave); //And increment number of followers for current author, also in Statistics table: authorEnt.followers.ForEach(folo => statEnt.followers_count += 1); statisticsLocal.Add(statEnt); } twitterContext.SaveChanges(SaveChangesMode.Batch); var traces = AuthorsTable.RetriveAllQueryTraces(); foreach (var trace in traces) { Console.WriteLine("coordinator was {0}", trace.Coordinator); } Console.WriteLine("Done!"); //Now every author will add a single tweet: Console.WriteLine("Now authors are writing their tweets.."); List<Tweet> tweetsLocal = new List<Tweet>(); List<FollowedTweet> followedTweetsLocal = new List<FollowedTweet>(); foreach (var auth in authorsID) { var tweetEnt = new Tweet() { tweet_id = Guid.NewGuid(), author_id = auth, body = "Hello world! My name is " + auth + (DateTime.Now.Second % 2 == 0 ? "." : ""), date = DateTimeOffset.Now }; TweetsTable.AddNew(tweetEnt); tweetsLocal.Add(tweetEnt); //We will update our statistics table statisticsLocal.First(stat => stat.author_id == auth).tweets_count += 1; //We also have to add this tweet to "FollowedTweet" table, so every user who follows that author, will get this tweet on his/her own wall! FollowedTweet followedTweetEnt = null; Author author = AuthorsTable.FirstOrDefault(a => a.author_id == auth).Execute(); if (author != default(Author) && author.followers != null) foreach (var follower in author.followers) { followedTweetEnt = new FollowedTweet() { user_id = follower, author_id = tweetEnt.author_id, body = tweetEnt.body, date = tweetEnt.date, tweet_id = tweetEnt.tweet_id }; FollowedTweetsTable.AddNew(followedTweetEnt); followedTweetsLocal.Add(followedTweetEnt); } } twitterContext.SaveChanges(SaveChangesMode.Batch); Console.WriteLine("Done!"); string separator = Environment.NewLine + "───────────────────────────────────────────────────────────────────────" + Environment.NewLine; Console.WriteLine(separator); //To display users that follows "Author8": Console.WriteLine("\"Author8\" is followed by:" + Environment.NewLine); try { Author Author8 = AuthorsTable.First(aut => aut.author_id == "Author8").Execute(); Author8.displayFollowers(); } catch (InvalidOperationException) { Console.WriteLine("\"Author8\" does not exist in database!"); } //To display all of user "Author15" tweets: Console.WriteLine(separator + "All tweets posted by Author15:" + Environment.NewLine); foreach (Tweet tweet in (from twt in TweetsTable where twt.author_id == "Author15" select twt).Execute()) tweet.display(); //To display all tweets from users that "Author45" follows: string author_id = "Author45"; Console.WriteLine(separator + string.Format("All tweets posted by users that \"{0}\" follows:", author_id) + Environment.NewLine); // At first we will check if specified above author_id is present in database: Author specifiedAuthor = (from aut in AuthorsTable where aut.author_id == author_id select aut).FirstOrDefault().Execute(); // it's another possible way of using First/FirstOrDefault method if (specifiedAuthor != default(Author)) { var followedTweets = (from t in FollowedTweetsTable where t.user_id == author_id select t).Execute().ToList(); if (followedTweets.Count() > 0) foreach (var foloTwt in followedTweets) foloTwt.display(); else Console.WriteLine(string.Format("There is no tweets from users that {0} follows.", author_id)); } else Console.WriteLine(string.Format("Nothing to display because specified author: \"{0}\" does not exist!", author_id)); //Let's check all of authors punctuation in their tweets, or at least, if they end their tweets with full stop, exclamation or question mark: List<string> authorsWithPunctuationProblems = new List<string>(); //To check it, we can use anonymous class because we are interested only in author_id and body of the tweet var slimmedTweets = (from twt in TweetsTable select new { twt.author_id, twt.body }).Execute(); foreach (var slimTwt in slimmedTweets) if (!(slimTwt.body.EndsWith(".") || slimTwt.body.EndsWith("!") || slimTwt.body.EndsWith("?"))) if (!authorsWithPunctuationProblems.Contains(slimTwt.author_id)) authorsWithPunctuationProblems.Add(slimTwt.author_id); if (authorsWithPunctuationProblems.Count > 0) { // Now we can check how many of all authors have this problem.. float proportion = (float)authorsWithPunctuationProblems.Count() / AuthorsTable.Count().Execute() * 100; Console.WriteLine(separator + string.Format("{0}% of all authors doesn't end tweet with punctuation mark!", proportion) + Environment.NewLine); // This time I will help them, and update these tweets with a full stop.. foreach (var tweet in TweetsTable.Where(x => authorsWithPunctuationProblems.Contains(x.author_id)).Execute()) { TweetsTable.Attach(tweet); tweetsLocal.Where(twt => twt.tweet_id == tweet.tweet_id).First().body += "."; tweet.body += "."; } twitterContext.SaveChanges(SaveChangesMode.Batch); } //Statistics before deletion of tweets: Console.WriteLine(separator + "Before deletion of all tweets our \"Statistics\" table looks like:" + Environment.NewLine); StatisticsTable.DisplayTable(); //Deleting all tweets from "Tweet" table foreach (var ent in tweetsLocal) { TweetsTable.Delete(ent); var statEnt = statisticsLocal.FirstOrDefault(auth => auth.author_id == ent.author_id); if (statEnt != default(Statistics)) statEnt.tweets_count -= 1; } twitterContext.SaveChanges(SaveChangesMode.Batch); //Statistics after deletion of tweets: Console.WriteLine("After deletion of all tweets our \"Statistics\" table looks like:"); StatisticsTable.DisplayTable(); //Logs: Console.WriteLine(separator + "Number of received logs: " + LogWriter.LogsTable.Count().Execute()); foreach (var log in LogWriter.LogsTable.Execute()) log.display(); LogWriter.StopWritingToDB(); }