Shipment Service
Cloud / Knowledge library
Azure Service Bus Topics
Provides durable topic subscriptions with filters and enterprise messaging features
Why learn Azure Service Bus Topics?
Teams use Azure Service Bus Topics to adopt publish-subscribe messaging without building the complete underlying platform themselves.
The problem it solves
Fans published events out to one or more asynchronous subscribers
Where it came from
Azure Service Bus Topics is Microsoft Azure's offering for publish-subscribe messaging. Its closest catalog counterparts are Amazon SNS and Google Cloud Pub/Sub; they address the same broad need but are not feature-for-feature identical.
Build your understanding
Work through these exercises in order. Try the task before opening a reference.
- Explain the main responsibility of Azure Service Bus Topics.
- Choose a workload that fits Azure Service Bus Topics.
- Identify one operational tradeoff of Azure Service Bus Topics.
- Compare Azure Service Bus Topics with Amazon SNS.
- Compare Azure Service Bus Topics with Google Cloud Pub/Sub.
Documentation and sources
- Microsoft Azure product catalog (azure.microsoft.com)
Connect the ideas
Alternatives
Real World Example
Global Logistics Event Distribution
Logistics companies managing diverse regional distribution centers that require real-time updates on shipment status.
The business problem
Monolithic notification systems struggle to route specific shipment events to relevant regional warehouses, leading to unnecessary data processing and latency.
How this topic solves it
Azure Service Bus Topics enable a publish-subscribe pattern where a single message sent to a topic is distributed to multiple subscriptions, each using filters to receive only relevant shipment updates.
- Create an Azure Service Bus Namespace and define a central Topic for shipment events.
- Configure multiple Subscriptions on the Topic, one for each regional distribution center.
- Apply SQL-based filters to each Subscription to isolate events by region or shipment priority.
- Publish shipment messages to the Topic using a unique Correlation ID.
- Implement message handlers in regional services to process filtered messages from their respective Subscriptions.
Shows how a single publisher sends messages to a topic, which then routes them to specific subscriptions based on defined filters.
ShipmentEvents
Filter: Region='North'
Filter: Region='South'
- Publisher → Sends Message → Topic
- Topic → Matches Filter → Subscription A
- Topic → Matches Filter → Subscription B
Expected business outcome
Regional services receive only the data they need, reducing local compute overhead and ensuring durable delivery even if a regional service is temporarily offline.
Limitations and checks
The complexity of managing numerous subscription filters can lead to maintenance overhead; verify filter effectiveness by monitoring the dead-letter queue for messages that fail to match any criteria.