Azure Service Bus Flashcards
what are topics & subscriptions?
Topics work on pub-sub model.
Broadcasts messages. Multiplexing.
Filter can be used on Topics to create subscription.
Subscription is equal to queue.
What are the pricing for Service Bus?
There are 2 tiers for Service Bus:
- Standard
- Premium
What is default messaging protocol for Service Bus?
AMQP, Advanced message queueing protocol
What are the two type of message when working with Messaging services?
Command: Azure Service Bus
Facts: Event hub (Time-series/Streaming data) & Event Grid (Discrete/Event data)
What are the key features of Azure Service Bus?
- Push/pull model
- central arbiter of state/truth of transition
- Helps in load-leveling the APIs
How to know when to use Azure Service Bus?
We should use Azure service bus when we know all the nouns involved in the communication:
- Who is sending the message?
- What is the message?
- Where is the message going to?
What are the two communication methods in Azure Service Bus?
- Point to point (Queue)
- Broadcast (Topic)
What are the attributes of the Azure Service Bus - Queue?
- Point to point
- Once ACK’ed the messages are never lost
- Receiver connect to the queue and retrieves the message (pull mechanism)
- Competing consumer pattern, scaling horizontally senders & receivers
What is Dead lettering?
- Once there is failure in message delivery, the message is pushed a sub-queue called Dead Letter queue where it can stay for as long as it is required
What are Subcription Filters?
These are filters that can be used to filter out messages in Topics that the subscriber doesn’t want to react to.
What are Message Sessions?
Group messages to be processed in a single session
What is TTL for messages?
This defines the lifetime of the message until it is picked up, once the message crosses the TTL value in the queue it is dropped and nobody can then consume it.
What is a Namespace in Azure Service Bus?
A namespace is a container for all messaging components (queues and topics). Multiple queues and topics can be in a single namespace, and namespaces often serve as application containers.
What is Message Sessions?
To realize a first-in, first-out (FIFO) guarantee in processing messages in Service Bus queue or subscriptions, use sessions. Sessions can also be used in implementing request-response patterns. The request-response pattern enables the sender application to send a request and provides a way for the receiver to correctly send a response back to the sender application.
What is Auto-Forwarding in Azure Service Bus?
The Auto-forwarding feature enables you to chain a queue or subscription to another queue or topic that is part of the same namespace. When auto-forwarding is enabled, Service Bus automatically removes messages that are placed in the first queue or subscription (source) and puts them in the second queue or topic (destination).
