The document discusses API discovery capabilities in IBM WebSphere Liberty that allow aggregating and discovering REST APIs across applications. It describes how Liberty supports auto-generating Swagger documentation and providing a UI for exploring APIs. It also demonstrates integrating Liberty APIs with IBM API Connect for management and consumption of APIs across hybrid environments.

1. Deploy and Access WebSphere Liberty and
StrongLoop REST Endpoints on IBM Bluemix
Arthur De Magalhaes

2. Presenter
Arthur De Magalhaes
WebSphere Liberty REST API architect
arthurdm@ca.ibm.com

3. Agenda
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• The API Economy
• What is Swagger
• StrongLoop
• Liberty API Discovery
• Demonstration
• Feedback

4. API Economy

5. API Economy
• APIs connect services in the Internet-of-things (IoT).
• Businesses provide and consume assets through APIs.
• REST APIs are client and server neutral, so often used as the bridge in
IoT.
• The number of available REST APIs increases daily, but without a
standard way of defining, exposing or discovering them.
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6. What is Swagger

7. Swagger Introduction
• Industry leading specification for defining REST APIs.
• Supports with both JSON and YAML formats.
• Large open source community with various projects on GitHub:
• Client code generation (26 languages).
• Server code generation (9 languages).
• Online editor and GUI.
• Over 2000 related open-source repository, with 15000 daily downloads.
• Base specification for Open API Initiative (https://openapis.org/), under
Linux foundation.
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8. Swagger YAML Sample
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paths:
/pet:
post:
tags:
- pet
summary: Add a new pet to the store
description: ''
operationId: addPet
consumes:
- application/json
- application/xml
produces:
- application/xml
- application/json
parameters:
- in: body
name: body
description: Pet object that needs to be added to the store
required: true
schema:
$ref: '#/definitions/Pet'
responses:
'405':
description: Invalid input
security:
- petstore_auth:
- 'write:pets'
- 'read:pets'

9. StrongLoop

10. StrongLoop (an IBM Company)
• Leader in enterprise Node.js.
• Over 130 npm modules.
• Major contributor to Open Source LoopBack and Express.
• Design REST APIs from data models.
• Top-down from design or from Swagger doc.
• Auto-generates Swagger 2.0
• Core member of Node.js Foundation.
• Available as part of API Connect’s “Create” license
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11. StrongLoop Arc
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12. Composer
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• Can create models from
DBs or from scratch.
• Provides a very nice
“top-down” experience.

13. Exploring your API
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• <app>/explorer
• Based on OS Swagger UI
• Can test APIs
• By default, Swagger available at:
<app>/explorer/swagger.json

14. StrongLoop in Bluemix
• You can deploy existing StrongLoop applications into Bluemix using
Cloud Foundry’s commands:
– cd <app-dir>
– cf api https://api.ng.bluemix.net
– cf login -u <bluemix-userid> -o <bluemix-userid> -s dev
– cf push <app-name>
• UI: http://<bluemix-host>/explorer
• Swagger doc: http://<bluemix-host>/explorer/swagger.json
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15. StrongLoop Boilerplates
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• Alternatively, there are 2 boilerplate packages to help you get started.

16. StrongLoop Boilerplates
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17. Liberty API Discovery

18. API Economy with Liberty
• What are the challenges when using Swagger with Java EE?
– Merging Swagger from annotations and standalone docs
– UI for rapid API development and unit testing
– Exploring all available APIs
– Generating code to call external services
• Liberty can help with all of these things!
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19. API Discovery
• All applications are discoverable in a single RESTful endpoint,
/ibm/api/docs
• Query parameter allows filtering based on context root.
• Support both JSON and YAML.
• Application participation can be configured in server.xml (location, on/off).
• Available through apiDiscovery-1.0 feature.
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Applications
Liberty
REST
Admin UI
API Connect

20. API Discovery User Interface
• Based on the Open Source Swagger UI.
• Available at /ibm/api/explorer.
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21. API Discovery Collective Support
• Enabling apiDiscovery-1.0 on a collective member will expose their
aggregated Swagger documentation available.
• Endpoints:
– /ibm/api/collective/docs
– /ibm/api/collective/explorer
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Admin UI
Repository
membersREST
controller
API Connect

22. API Discovery Subscription
• POST ibm/api/docs/subscription
• Request:
{ docType: string}
• Returns:
{ feedURL : wss://ibm/api/docs/subscription/websocket/{id}, feedType: websocket }
• The client opens WSS connection and receives updates in real-time
• Equivalent collective support at /ibm/api/collective/docs/subscription
• Works with either webSocket-1.0 or webSocket-1.1
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23. API Discovery in Bluemix
• Push a Liberty package into Bluemix
• cf push <yourappname> -p defaultServer
• Creates an auto-discoverable container in the cloud.
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Admin UI
app
app
app
WLP
API Connect

24. C
M
M
Pulling Liberty Assets from API Connect
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API Connect
Hybrid Liberty + StrongLoop Collective
swagger.json

25. Pushing Standalone Assets into API Connect
Continuous Integration
product.json
Source Repository
Swagger
processor
API Connect
CLI
PUBLIC | DEDICATED | LOCAL
API Connectproduct.json +
swagger.json
Developer

26. Pushing Liberty Assets into API Connect
Hybrid Liberty + StrongLoop Collective
PUBLIC | DEDICATED | LOCAL
API Connect
Administrator
product.json
product.json
C
M
M
or
product.json +
swagger.json
Developer
Continuous Integration
deploy
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27. WebSphere Developer Tools Support
• Authoring Swagger document (main doc or stub) through templates
and skeleton
• Includes JSON and Swagger-based validation.
• Auto-generate JAXRS 2.0 client from Swagger document or URL
• Can point to a running Liberty instance or Collective Controller and generate a
JAXRS client that can connect to any of the exposed services!
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28. Demonstration