Exemple #1
0
        static void Main(string[] args)
        {
            Diagnostics.CassandraTraceSwitch.Level = TraceLevel.Verbose;
            CassandraLogWriter      LogWriter = new CassandraLogWriter();
            TextWriterTraceListener twtl      = new TextWriterTraceListener(LogWriter);

            Trace.Listeners.Add(twtl);


            Console.WriteLine("Connecting, setting keyspace and creating Tables..");
            Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en-US");

            Cluster cluster = Cluster.Builder().AddContactPoint("127.0.0.1").Build();

            using (var session = cluster.Connect())
            {
                var keyspaceName = "test" + Guid.NewGuid().ToString("N");

                try
                {
                    session.ChangeKeyspace(keyspaceName);
                }
                catch (InvalidQueryException)
                {
                    session.CreateKeyspaceIfNotExists(keyspaceName);
                    session.ChangeKeyspace(keyspaceName);
                }

                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       = 50;
                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);
                        }
                    }
                }


                // 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);

                if (authorsWithPunctuationProblems.Count > 0)
                {
                    // 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();

                Console.WriteLine(separator + "Deleting keyspace: \"" + keyspaceName + "\"");
                session.DeleteKeyspaceIfExists(keyspaceName);
            }
            Console.WriteLine("Done! Press any key to exit..");
            Console.ReadKey();
        }
        static void Main(string[] args)
        {
            Diagnostics.CassandraTraceSwitch.Level = TraceLevel.Verbose;
            CassandraLogWriter LogWriter = new CassandraLogWriter();
            TextWriterTraceListener twtl = new TextWriterTraceListener(LogWriter);

            Trace.Listeners.Add(twtl);

            Console.WriteLine("Connecting, setting keyspace and creating Tables..");
            Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en-US");

            Cluster cluster = Cluster.Builder().AddContactPoint("cassi.cloudapp.net").Build();

            using(var session = cluster.Connect())
            {
                var keyspaceName = "test" + Guid.NewGuid().ToString("N");

                try
                {
                    session.ChangeKeyspace(keyspaceName);
                }
                catch (InvalidQueryException)
                {
                    session.CreateKeyspaceIfNotExists(keyspaceName);
                    session.ChangeKeyspace(keyspaceName);
                }

                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 = 50;
                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);

                // 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();

                Console.WriteLine(separator + "Deleting keyspace: \"" + keyspaceName + "\"");
                session.DeleteKeyspaceIfExists(keyspaceName);
            }
            Console.WriteLine("Done! Press any key to exit..");
            Console.ReadKey();
        }