Azure - Queues

Azure Queue Storage provides cloud messaging between application components. In designing applications for scale, application components are often decoupled, so that they can scale independently. Queue storage delivers asynchronous messaging for communication between application components, whether they are running in the cloud, on the desktop, on an on-premises server, or on a mobile device. Queue storage also supports managing asynchronous tasks and building process workflows.

It is a FIFO approach

Storage Account > Queue > Messages

Important Classes & Methods

Class: CloudStorageAccount
Method: CreateCloudBlobClient

Class: CloudQueueClient

Class:CloudQueue
Method: CreateIfNotExist
Method: PeekMessge
Method: UpdateMessge
Method: DeleteMessge

---Dequeue--
Method:GetMessage
Method:GetMessages - Read all visible messages or no. of messages you passed as parameter of the queue.

Message visibility to other clients, time is 30 sec by default. While Fetching message with GetMessage or updating with UpdateMessage you can change default visibility time and set as you wish, with passing a TimeSpan object as a parameter.

A message must be processed by one client only 




Dequeue a message
GetMessage   >  Process Message > Delete Message

GetMessage: Fetch message and block that message to other clients that means it will not visible to other clients for visibility time.
You need to process and delete this message before visible time finishes. Because after that, the message will be visible to other clients and another client may block that.

PeekMessage: It returns first available message of queue and do not block that message like GetMessage method.
It means parallel other clients may also read the same message. 

Class: CloudQueueMessage
Method: SetMessageContent
Property: Id
Property: PopupReceipt