APIs have become ubiquitous as a way of exposing the capabilities of the enterprise both internally and externally. However, are APIs alone enough? There is a strong resurgence in interest in asynchronous communication and event driven architecture. Applications want to receive events immediately so they can respond in real time, and furthermore they also want the benefit of being decoupled from the availability and performance characteristics of the systems providing that data. However, whilst the way that APIs are socialised, exposed, versioned etc. is well matured in the form of API management technology. We are now on the cusp of seeing first class support for event endpoint management to provide the same sophistication for discovering, exposing and consuming events.

1. Should we manage events like APIs?
Kim Clark
Integration Architect and Strategist
IBM
kim.clark@uk.ibm.com
Alan Chatt
Offering Manager for Event-Driven Integration
IBM Automation
alan.chatt@uk.ibm.com

2. API Management: More than just a gateway
Developer
Portal
API
Manager
API Implementation
API gateway
API Gateway:
• Decoupling/routing
• Traffic management
• Security
• Translation
Developer portal:
• API discovery
• Self-service
– Onboarding
– API subscription
• Account usage analytics
API Manager:
• API/plan/product design
• Access management
• Policy administration
• API plan usage analytics
The API implementation should
not be burdened with the
complexities of API exposure.
API Management handles the consumer-focused aspects of the API lifecycle
• Control point: Consistent provision of routing, versioning, traffic management, security, logging.
• Socialization: Enables discovery, documentation, and self-subscription, analytics.
© 2021 IBM Corporation

3. Creating truly independent digital applications requires
asynchronous communication as well as APIs
3
© 2021 IBM Corporation
Microservice Application
SoR SoR SoR
SoR
API
consumption
Event
Stream
consumption
Agility
Innovate rapidly
without
affecting other
components
APIs
Are simplest to use, but
create a real-time
dependency on the
underlying system of record
Truly independent, decoupled microservice components enable
To provide those benefits they need to be independent
of one another, and from the systems of record
Scalability
Scale only what
you need, and
only when you
need to
Resilience
Fail fast, return
fast, without
affecting other
components
Event streams
Enable microservices to
build decoupled views of
the data and respond to
real time events
API and Event management
µService
µService
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µService
µService
µService
µService
µService µService
http://ibm.biz/eda-resurgence-slides

4. Boundaries make complex environments manageable
4
Managed API gateways define and enforce application boundaries
µService
µService
µService
µService
µService
µService
µService
µService
µService
µService
µService
µService
µService
µService µService
µService
µService
Silo
application
Silo
application
µService
µService
API
Application
boundary
Microservice
component
API
https://developer.ibm.com/apiconnect/2018/10/09/apis-microservices-defining-boundaries
& Event management
(sync and async)

5. High level API and Event interaction patterns
Request Action
Request State
Notifications
Ack
Req
API
Resp
Req
API
Topic
Topic
Request State
(pre-received)
5

6. Event sourcing
Local “event sourced”
read-optimized datastore
Read
implementation
A
Read
implementation
B
Local datastore Local datastore
Subscribe
and
consume
Direct invocation
Event stream
Subscribe
and
consume
“Event Sourced” implies the use of an
event log as the primary datastore
Application/Context
boundary
Event Log
… 4 5 6 7 …
Command
implementation
COMMAND
QUERY
Exposed API
, and CQRS
© 2021 IBM Corporation https://ibm-cloud-architecture.github.io/refarch-eda 6

7. Event sourcing/CQRS within a bounded context
vs (inter) domain events
CQRS and Event Sourcing patterns are typically scoped to
within a bounded context. From outside the context, the event
sourced nature of the implementation should be hidden.
Bounded Context
Event Log
COMMAND
QUERY
Bounded Context
Only selected events (and for that matter APIs) should
be exposed across bounded contexts. Their data models
should be decoupled from the internal model.
Internal
events
(inter) domain events
API & Event Management
© 2021 IBM Corporation https://ibm.biz/eventprojectionspaper 7

8. Event Endpoint Management
Easily found,
quickly consumed
• Described
• Catalogued and
discoverable
• Policy controlled
access
Completely
De-coupled
• Self-service
consumption
• No technology ties
between provider
and consumers
• No operational ties
Consumed
reliably
• Consumption
options suitable for
many application
types
• Replay history,
durable subs,
horizontal scale
Delivered in time
to be useful
• Latency measured
in seconds not
minutes
• Delivered rather
than polled
8
Transport: Event Distribution Event Endpoint Management
https://www.ibm.com/cloud/blog/multi-form-api-management-is-it-an-api-or-not
© 2021 IBM Corporation

9. IBM Confidential
Decentralised
Discoverable
Described
Decoupled
E n g a g i n g a n d
I n t e l l i g e n t a p p s
R e s p o n s i v e
e x p e r i e n c e s
Event
Transport
Ingredients for an enterprise Events Backbone

10. IBM Confidential
Describing Events
Events need to be described so developers can
quickly understand what they are and how to
consume them
• Understood by people
• Supported by tooling
• Consistent with API definitions
Decentralised
Discoverable
Described
Decoupled
E n g a g i n g a n d
I n t e l l i g e n t a p p s
R e s p o n s i v e
e x p e r i e n c e s
Event
Transport
IBM already contributing into the Async API specification
https://github.com/asyncapi/bindings/tree/master/ibmmq
Ingredients for an enterprise Events Backbone

11. IBM Confidential
Decentralised
Discoverable
Described
Decoupled
E n g a g i n g a n d
I n t e l l i g e n t a p p s
R e s p o n s i v e
e x p e r i e n c e s
Event
Transport
Discovering events exists
An interface that cannot be found is no use to
anyone
• Catalogued in one place
• Searchable
• Understandable and ready to consume
Ingredients for an enterprise Events Backbone

12. IBM Confidential
Decentralised
Discoverable
Described
Decoupled
E n g a g i n g a n d
I n t e l l i g e n t a p p s
R e s p o n s i v e
e x p e r i e n c e s
Event
Transport
Decentralise access
Innovation flows best when people have the
freedom to explore
• Self-service access
• Policy based controls and enforcement
• Trackable use
Ingredients for an enterprise Events Backbone

13. IBM Confidential
Decentralised
Discoverable
Described
Decoupled
E n g a g i n g a n d
I n t e l l i g e n t a p p s
R e s p o n s i v e
e x p e r i e n c e s
Event
Transport
Decoupled systems
Loosely coupled systems are more flexible and
less fragile. The technology emitting the event
should not dictate how it must be consumed
• Data transformation and enrichment
• Protocol translation
• Interface versioning
• Connectivity to anything
Ingredients for an enterprise Events Backbone

14. IBM Cloud Pak for Integration with Confluent
API Lifecycle
Management
Application &
Data Integration
Enterprise
Messaging
High Speed Data
Transfer
Secure Gateway
Governance Asset Sharing
Unified User Experience
IBM containerized software
Container platform and operational services
© 2021 IBM Corporation
14
Cloud Hybrid On-premises
Cloud Pak for Integration
Event Endpoint
Management
Cloud Pak for Integration,
in partnership with
Confluent, provides the
broadest range of
integration capabilities on
the market.
As part of our commitment
to flexibility, we now offer
customers the choice of
Kafka providers, while
creating new cross-
platform connectivity.