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Event Mesh - Comprehensive Reference

Source: SAP BTP Integration Suite Documentation Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/tree/main/docs/ISuite Last Updated: 2025-11-22

Overview
Core Concepts
Topics
Queues
Event Brokers
Message Clients
Webhook Subscriptions
Best Practices

Overview

Event Mesh is a capability within SAP Integration Suite that enables event-driven architecture (EDA) for publishing and consuming business events across your enterprise ecosystem.

Key Benefits:

Decouple producers from consumers
Enable real-time event processing
Scale independently
Support async communication patterns

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/event-mesh-3129673.md

Core Concepts

What is an Event?

An event represents "a change in the state of data" - something that happens in a system that other systems may need to know about.

Examples:

Order created in e-commerce system
Temperature sensor reading changed
Customer record updated in CRM
Payment processed

Event-Driven Architecture (EDA)

EDA helps enterprises "act on new data in near-real time" by:

Publishing events when state changes occur
Subscribing to events of interest
Processing events asynchronously
Decoupling system dependencies

Event Messages

Events generate messages to communicate event data between systems. Messages contain:

Event type/topic
Payload (event data)
Metadata (timestamp, source, etc.)

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/what-are-events-9a5bf90.md

Topics

Topics classify event messages using a hierarchical structure.

Topic Structure

Format: level1/level2/level3/.../levelN

Example:

sales/orders/created
sales/orders/updated
sales/orders/cancelled
inventory/stock/updated
inventory/stock/depleted

Topic Naming Rules

Rule	Requirement
Length	Maximum 150 characters
Characters	Alphanumeric, underscore, period, hyphen
Segments	Minimum 2, maximum 20
Separator	Forward slash (/) only
Start/End	Cannot start or end with /
Empty segments	Not allowed

Topic Wildcards

Asterisk (*): Matches entire subtree, must be at end

sales/*          → matches sales/orders, sales/returns, etc.
sales/orders/*   → matches sales/orders/created, sales/orders/updated

Plus (+): Matches single segment

sales/+/created  → matches sales/orders/created, sales/returns/created
+/orders/+       → matches sales/orders/created, purchases/orders/updated

Topic Subscriptions

Queues subscribe to topics to receive matching events:

Subscription: sales/*/created
Matches:
  ✓ sales/orders/created
  ✓ sales/returns/created
  ✓ sales/quotes/created
  ✗ sales/orders/updated

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/what-are-topics-and-topic-subscriptions-1712c0d.md

Queues

Queues are endpoints that persist messages for consumers.

Queue Definition

"A queue is an endpoint configured with topic subscriptions that can publish messages to and consume messages from."

Queue Types

Type	Description	Use Case
EXCLUSIVE	Only one consumer can access at a time	Serial processing, single consumer
NON-EXCLUSIVE	Multiple consumers can access	Parallel processing, load balancing

Queue Workflow

1. Producer → publishes message → Event Mesh
2. Event Mesh → matches topic → stores in queue
3. Queue → retains message → until consumed
4. Consumer → connects → receives message
5. Consumer → acknowledges → message removed

Queue Features

Subscribe to multiple topics
Persist messages until consumed
Support guaranteed delivery
Enable message acknowledgment
Allow dead-letter handling

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/queues-99b7501.md

Event Brokers

Definition

An event broker is "middleware that mediates the communication of event messages between producers and consumers using the various message exchange patterns."

Broker Functions

Receive events from producers
Route based on topics/subscriptions
Store for persistence
Deliver to subscribers
Acknowledge successful delivery

Deployment Options

Type	Description
Hardware appliance	Physical messaging hardware
Software	On-premise software installation
Cloud SaaS	SAP Event Mesh service

Message Exchange Patterns

Pattern	Description
Publish/Subscribe	One-to-many distribution
Point-to-Point	One-to-one delivery
Request/Reply	Synchronous with response

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/what-are-event-brokers-f72428f.md

Message Clients

Message clients connect applications to Event Mesh.

Creating a Message Client

Via BTP Cockpit:

Navigate to Event Mesh service
Create message client instance
Configure queue subscriptions
Generate credentials

Via CF CLI:

cf create-service enterprise-messaging default my-event-mesh \
  -c '{"emname": "my-client", "options": {"management": true, "messaging": true}}'

Client Configuration

{
  "emname": "my-message-client",
  "namespace": "company/department/app",
  "rules": {
    "topicRules": {
      "publishFilter": ["${namespace}/*"],
      "subscribeFilter": ["${namespace}/*", "shared/*"]
    },
    "queueRules": {
      "publishFilter": ["${namespace}/*"],
      "subscribeFilter": ["${namespace}/*"]
    }
  }
}

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/configure-a-message-client-867c517.md

Webhook Subscriptions

Enable HTTP-based event delivery without persistent connections.

How Webhooks Work

1. Event published → Event Mesh
2. Event Mesh → matches subscription
3. Event Mesh → HTTP POST → Webhook URL
4. Webhook endpoint → processes event
5. Endpoint → returns 2xx → acknowledged

Webhook Configuration

Parameter	Description
URL	Target endpoint for events
Topic subscription	Topics to receive
Authentication	Basic, OAuth, Certificate
Retry policy	Retry on failure

Webhook vs Queue Consumption

Aspect	Webhook	Queue
Connection	HTTP push	Protocol connection
Persistence	Limited	Full
Ordering	Not guaranteed	Guaranteed
Throughput	Lower	Higher
Simplicity	Higher	Lower

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/webhook-subscriptions-58e3729.md

Integration with Cloud Integration

AMQP Adapter

Connect iFlows to Event Mesh using AMQP adapter.

Sender Adapter (consume events):

Adapter Type: AMQP
Transport Protocol: WebSocket
Host: messaging-service-host
Queue Name: queue:my-queue
Authentication: OAuth2 Client Credentials

Receiver Adapter (publish events):

Adapter Type: AMQP
Transport Protocol: WebSocket
Host: messaging-service-host
Topic: topic/my/event
Authentication: OAuth2 Client Credentials

Event-Driven iFlow Pattern

┌──────────────┐    ┌────────────────┐    ┌──────────────┐
│  Event Mesh  │ →  │  iFlow (AMQP)  │ →  │   Backend    │
│    Queue     │    │   Processing   │    │    System    │
└──────────────┘    └────────────────┘    └──────────────┘

Best Practices

Topic Design

Use hierarchical structure

organization/domain/entity/action
acme/sales/order/created

Be specific but not too granular
- Good: sales/orders/created
- Too broad: sales/event
- Too specific: sales/orders/created/usa/region1/store5
Use consistent naming conventions
- lowercase
- no spaces
- descriptive names

Queue Design

One queue per consumer type
- Order processing queue
- Analytics queue
- Audit queue
Use dead-letter queues
- Handle failed messages
- Enable retry analysis
Set appropriate TTL
- Time-to-live for messages
- Prevent queue overflow

Error Handling

Acknowledge after processing
- Don't acknowledge before work is done
- Use transactions when needed
Implement retry logic
- Exponential backoff
- Maximum retry count
Use dead-letter handling
- Route failed messages
- Enable investigation

Glossary

Term	Definition
Event	Change in system state
Topic	Hierarchical event classification
Queue	Persistent message endpoint
Subscription	Topic pattern for queue
Producer	Application publishing events
Consumer	Application receiving events
Broker	Middleware routing events
Webhook	HTTP-based event delivery

Documentation: https://github.com/SAP-docs/sap-btp-integration-suite/blob/main/docs/ISuite/glossary-for-event-mesh-501ba2d.md

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