Introducing Windows Azure- P24:The cloud platform is getting more and more attractive to the computing world. Today, service-oriented architecture (SOA) and aspect-oriented programming (AOP) techniques are widely used in enterprise solutions. A question an IT management team or a software development team may ask is, what is the next trend going to be? Cloud computing seems to be the right answer. | CHAPTER 3 WORKING WITH CLOUD QUEUE AND BLOB STORAGE if DeleteEntry int index string blobName string index .Value if blobName blobName catch DataBind Listing 3-13. Command Handler Used to Interprete Which Blob Item Row Has Been Selected protected void RowCommandHandler object sender GridViewCommandEventArgs e try if DeleteEntry int index string blobName string index .Value if blobName blobName catch DataBind In addition to using ListBlobs to retrieve blob records in a C class as I demonstrated the blob record can also be retrieved using a REST query with tools or applications such as Fiddler that can generate web HTTP GET POST UPDATE requests. Figure 3-9 shows an example of the REST query results against our blob storage. The tool used to do the REST query is Fiddler 2. The example of syntax for the query string is as follows http 10000 devstoreaccount1 blobpayload caa95517-3414-4bc2-8f16-0a44a6f156e1xml The return code for a success REST query is 200. 88 CHAPTER 3 WORKING WITH CLOUD QUEUE AND BLOB STORAGE Figure 3-9. REST query results of blob data using Fiddler 2 HTTP debug tool Creating a Loosely Coupled Event-Driven System Using both queue and blob storage we can easily design loosely-coupled event-driven applications. Figure 3-10 is the case study diagram of this type of application design. The concept is very simple and straightforward as the diagram shows. The following are the highlights of the design concepts. Define an events listener to monitor a specific event. The event is fired at the time a message is delivered to the queue. A listener from the server side should be constructed with two components a dedicated queue to accept a message with a specific topic queue name and an event handler. For .
