Sunday, March 13, 2016

Common Gotchas

                                                                   
                                                               Common Gotchas



1)   Extra character in Certificate Thumbprint – Go to Windows MMC, add the certificates snap-in (Ctrl M), select any certificate properties and copy-paste its thumbprint in notepad to see it.


2)     Enterprise library Semantic logging (out-of-process) service not logging anything – Restart the service.

3)     Enterprise library Semantic logging will not write anything if any one of the parameter passed is null. Example  -
this.WriteEvent(2, FirstName, LastName, EncSSN, City);
will not write if anything if just “City” is null. 

4) While configuring Quartz.NET scheduler with AdoNetJobStore (needed for clustered scenario), make sure no other instance of Quartz.NET scheduler is pointing to the same job store (database). Example - SIT Env Quartz.NET jobstore might be pointing to UAT Env. jobstore.

5) Sharing a folder in Windows will update the existing ACL list of the children folder. For example - Sharing the inetpub > "wwwroot" folder with read-only permissions for some colleagues removed "NetworkService" and "IIS_IUSRS" users from all its virtual directories physical folders. 

ReSubmitting messages from ServiceBus Deadletter queue



ReSubmitting messages from ServiceBus Deadletter queue


Resubmitting messages, which do not require any change, from deadletter queue is straightforward and can be done using Service Bus Explorer tool.

However if the messages need change (say for example – because of bug – there is a special character which needs to be stripped off from the messages), ServiceBusExplorer would not do it. This can be done by using a custom tool/program to retrieve the messages from deadletter queue, store it somewhere, do the necessary modification and push the message back to the service bus. (Note – The earlier deadletter messages should be deleted (received)).
The sample code for reading messages from deadletter queue can be taken the open source ServiceBusExplorer tool itself. Program below –


class Program
    {
        private static int MaxBufferSize = 262144; // 256 KB

        static void Main(string[] args)
        {

            Uri uri = new Uri(@"sb://" + ConfigurationManager.AppSettings["SbHost"] + "." + ConfigurationManager.AppSettings["Domain"] + "/" + ConfigurationManager.AppSettings["Namespace"]);
            TokenProvider tokenProvider = TokenProvider.CreateSharedAccessSignatureTokenProvider(ConfigurationManager.AppSettings["KeyName"], ConfigurationManager.AppSettings["SharedAccessKey"]);
            MessagingFactory factory = MessagingFactory.Create(uri, tokenProvider);

            SubscriptionClient subsClient = factory.CreateSubscriptionClient(ConfigurationManager.AppSettings["Topic"], ConfigurationManager.AppSettings["Subscription"] + "/$DeadLetterQueue");

            var listMessages = subsClient.PeekBatch(Convert.ToInt32(ConfigurationManager.AppSettings["PeekMessageCount"]));           

            foreach (var bm in listMessages)
            {
                string messageText = null;
                Stream stream = bm.GetBody<Stream>();
                var element = new BinaryMessageEncodingBindingElement
                {
                    ReaderQuotas = new XmlDictionaryReaderQuotas
                    {
                        MaxArrayLength = int.MaxValue,
                        MaxBytesPerRead = int.MaxValue,
                        MaxDepth = int.MaxValue,
                        MaxNameTableCharCount = int.MaxValue,
                        MaxStringContentLength = int.MaxValue
                    }
                };
                var encoderFactory = element.CreateMessageEncoderFactory();
                var encoder = encoderFactory.Encoder;
                var stringBuilder = new StringBuilder();
                var message = encoder.ReadMessage(stream, MaxBufferSize);
                using (var reader = message.GetReaderAtBodyContents())
                {
                    var settings = new XmlWriterSettings { Indent = true };
                    using (var writer = XmlWriter.Create(stringBuilder, settings))
                    {
                        writer.WriteNode(reader, true);
                    }
                }
                messageText = stringBuilder.ToString();
                Console.WriteLine(messageText);
                stream.Dispose();
                File.WriteAllText(ConfigurationManager.AppSettings["PathToStoreMessages"] + bm.MessageId + ".txt", messageText);
            }



        }


    }