- Azure Service Bus is a multi-tenant cloud messaging service that provides a fully managed enterprise integration message broker. - It includes queues for point-to-point messaging and topics with subscriptions for publish-subscribe messaging patterns. - Messages in Service Bus can contain user-defined properties and a body, and subscriptions can apply filters on properties and actions like routing.

1. Azure Messaging Services #1
RIYADH 7
13 April 2019
Microsoft Riyadh

2. Amr Badawy
Technical Consultant

3. Agenda
 Introduction
 Messaging : The Journey
 Queueing : Concepts & Use cases
 Azure Messaging Family
 Azure Service Bus : Brokered Messaging
 Azure Service Bus : Advanced Features
 Event Grid & Event Hub
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4. Messaging
The Journey
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5. Mailbox
Pub/Sub
Queue!5

6. Main Office
Office #2
Office #3
Office #4
Office #10 Office #11
Messaging in our Life
• Direct Communication
• Async two-way communication
 Filtering | Chaining | Expiration
 Ordering | Forwarding | Scheduling
 Dead-lettering | Batching | Security
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8. Message Queuing
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In modern architecture, applications are decoupled into smaller, independent building blocks that are
easier to develop, deploy and maintain.
Message Queues
• Provide Async communication for distributed system (Key)
• Temporary Storage Location for messages pending delivery to a destination component.
• Buffer between producer & consumer

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Message Queuing Essentials
Regardless of the technology, most
Message Queues support three
fundamental operations:
1. Sender can post a message to the
queue.
2. Receiver can retrieve a message from
the queue (the message is removed
from the queue).
3. Receiver can examine (or peek) the
next available message in the queue
and decide whether to removes it or
leave it for another receiver to handle.

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Key Messaging Patterns (Basic)
• Client sends message
• Consumer retrieve message and process
• One-way messaging
Fire-and-Forget
• Client sends message (reply address)
• Consumer retrieve message and process and
send response
• Client retrieve response message
• Async two-way communication
Request-Response

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Key Messaging Patterns (Basic)
• Subscribers register to queue (continues)
• Publisher sends message
• Queue forward message to Subscribers
• Subscribers retrieve message and process
• Broadcast messaging
Publish-Subscribe

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Asynchronous Messaging Scenarios
• Decoupling workloads » decouple the logic that generates work from that logic that performs the work.
• Temporal decoupling » sender and receiver do not have to be running at the same time.
• Load balancing » distribute processing across servers and improve throughput
• Senders may post a large number of requests to a queue that is serviced by many receivers.
• Receivers can run on different servers to spread the load.
• Receivers can be added/removed dynamically to scale out/in (autoscaling) » Improve Scalability
• Load leveling » [Queue-Based Load Leveling pattern]
• Heavy load from senders >> increasing receivers to handle this work could overwhelm the system.
• acts as a buffer, and receivers work without stressing the system.
• minimize the impact of peaks
• Cross-platform integration » senders and receivers agree on a common format for messages and their contents.
• Deferred processing »
• Reliable messaging »
• The sender is not blocked unless it loses connectivity with the queue.
• message can wait untill a destination component is ready to process

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Implementing Asyn Messaging’s Considerations
• Message Ordering » Priority Queue pattern
• Message Grouping »
• Idempotency » https://blog.jonathanoliver.com/idempotency-patterns/
• Repeated messages » Duplicate Message Detection
• Handling Failures »
• Poison messages » it is necessary to be able to detect and discard them
• Message expiration » message might have a limited lifetime
• Retry

14. Message Queuing | Misc.
Terms
• Publisher / Sender / Producer » push / send
• Subscriber / Receiver / Consumer / Listener » pull /receive / retrieve
• MoM - Message-oriented Middleware / Message Queuing / Messaging
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Examples
• Book a ticket ( Booking Service )
1. Change state in DB
2. Notify Event Owner
3. Create an invoice a PDF
4. Send a confirmation email (invoice attached)
• Picture Resize
• Pushing a tweet :: How twitter write new tweet for followers
• Notification Service >> send many emails
• Logging service >> keep in buffer and then write to DB
• RFID Reader

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Azure Messaging Services

16. 16

17. Azure Messaging Services
• In the early days of Microsoft Azure, there were only a couple message queue service:
• Storage Queue & Service Bus
• Why do azure offer many messaging services ?
• One size doesn’t fit all
• Service Bus :: Enterprise Messaging &
• Event Hub :: Streaming platform
• Event Grid :: Event Distribution
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Azure Relay enables bi-directional, point-to-point network connection bridging.

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Azure Service Bus
Multi-tenant cloud messaging service & simple hybrid integration
Fully managed enterprise integration Message Broker

19. Azure Service Bus | Components
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 Namespace : Scoping container for all messaging entities » Application Container
 Queue >> point-to-point messaging
 Topic
 Subscription
 Managing Components
 Portal
 Custom Code
 PowerShell
 Http/Rest
 Azure Resource Manager

20. Demo #1
• Create Namespace
• Create Queue
• Create Topic & Subscription
• Managing SAS
• Creating by Code
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21. Azure Service Bus | Message
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 Header - Properties
 MessageId
 SessionId
 Label
 CorrelationId
 UserProperties <Dictionary>
• SequenceNumber : Gets the unique number assigned to a message by Service Bus.
• EnqueuedSequenceNumber : For messages that have been auto-forwarded, this property
reflects the sequence number that had first been assigned to the message at its original point of
submission. This property is read-only.
 Body
 Content (Binary) » Serialized Object
 Limitation
 Size = 256KB >> 1MB
 Header Size = 64 KB

22. Demo : Message
• Create Message
• Send & Receive
• Receive Modes
• Receive Batch
• Duplication Detection
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23. Message | Pub/Sub
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 Publish-Subscribe messaging
 Topic / Subscription » every subscription gets a copy of each message sent to a topic, which enables
a broadcast pattern.
 Subscription Rules (Filters & Actions)
 Ex : order organized by region
 Filters
 user-defined properties and system properties
 cannot evaluate the message body
 SQL Filter : SQL-like conditional expression
 NOT - AND - { = | <> | != | > | >= | < | <= }
• IS [NOT] NULL - [NOT] IN () - [NOT] LIKE
• sys.Label LIKE '%bus%'` OR `user.tag IN ('queue', 'topic', 'subscription’)
• sys.Label = 'important'
 Correlation Filter : equal only
 Actions :
 With SQL filter conditions, you can define an action for adding, removing, or replacing
properties and their values.
• Enable two further groups of patterns: partitioning and routing.

24. Demo : Correlation & Session
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• Transient

25. Azure Service Bus | Advanced features
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 Message sessions »
 Auto-forwarding »
 Dead-lettering »
 Scheduled delivery »
 Message deferral »
 Batching »
 Transactions »
 Filtering and actions »
 Auto-delete on idle »
 Duplicate detection »
 Handling Large Messages » claim-check pattern

26. Misc.
• Messaging Protocols :
• AMQP
• MQTT
• Messaging vs Events
• SDK for Service Bus (2)
• https://www.nuget.org/profiles/nugetservicebus
• Azure Messaging by the numbers (2017)
• 700B msg ops on ASB / month
• 100K DA SB Namespace
• 5.1T request per week in Event Hub
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27. Misc. | Delivery
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• Transaction-based Delivery
• Timeout-based Delivery
• Timeout-based Message Processor

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Messaging
is how different application components in a loosely-coupled
microservice architecture can communicate with each other

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Questions

30. Thanks 