Presented at JAX London 2013 Hypermedia or HATEOAS APIs get a lot of air cover but there aren't many of them in the wild. This session will summarize the challenges that exist when building hypermedia REST API’s and explain why it’s worth it. We’ll take a comparative look at various different approaches for using hypermedia in a typical REST API, before taking a closer look at an approach that automatically generates links from a semantically rich API definition.

1. Are
‘Hypermedia
API’s’
just
Daniel Feist, MuleSoft
Aaron Phethean, Temenos
Hype?

2. Introductions
● Founded 2006 by Ross Mason, to ‘Take
the donkey work out of integration’.
● Now the most widely used integration
platform for connecting SaaS and
enterprise applications in the cloud and
on-premise
All contents Copyright © 2013, MuleSoft Inc.
Daniel Feist,
Principal Architect
@dfeist
*

3. Introductions
Aaron Phethean
Product Manager
@aphethean
• Founded in 1993; listed on the Swiss Stock Exchange (SIX: TEMN)
• Market leading provider of banking software systems to retail, corporate,
universal, private, Islamic, microfinance and community banks, wealth
managers, and financial institutions
• Headquartered in Geneva and with more than 59 offices worldwide
• 1,500 customer deployments in more than 140 countries across the world.
All contents Copyright © 2013, MuleSoft Inc.
*

4. Goals
Levels of Hypermedia and advantages
Objective view
Avoid bigotry
New ideas
Propose and review REST DSLs
Tips & advice
Real world usage of Hypermedia
*

5. What is a Hypermedia API?
*

6. Whats Hype?
*

7. Whats Hype?

8. Hypermedia APIs - Innovation trigger?
?
*

9. Hypermedia APIs –
Enlightenment; productivity?
?
*

10. Hypermedia API’s
Inflated expectations?
?
*

11. Hypermedia APIs - Trough of disillusionment?
?
*

12. Where are Hypermedia APIs?
*

13. So .. this all just Hype?
• Prevent breakage
• Enabling discoverability
• Standardising API clients

14. Is
‘The Web’
just
Hype?

16. HTML Links
*

17. The Chasm
Hypermedia
API’s
L2 API’s
*

18. Why haven’t Hypermedia
API’s taken off?

19. The User

20. The User..

21. The User..

22. The Contract

23. A Typical API Contract...
*

24. Web Contract?
● Data
● Hypermedia
Controls (links)
● Presentation
*

25. Hypermedia Type for API’s
*

26. No Standardized Hypermedia Type
Hypermedia Type
Style
Version
HTML
Enrich
4.0.1
HTML Microformats
Enrich
XML
Enrich
1.1
ATOM
Wrap
RFC
HAL
Enrich
Draft
Collection-JSON
Wrap
Draft
Custom Media-Types
*

27. Limited Standard Link Relations
*

28. The Client

29. A Client

30. Who leads who?
*

31. A User-Agent
*

32. Hypermedia
Maturity Levels

33. Hypermedia Maturity Levels
Glory of Hypermedia
Shared Vocabulary
Interaction Services
Data Services
Level 2

34. Level 2
• Defines entities at URIs w/ flat or
CRUD type services
• No links between resources
• Projects / examples
- Twitter
- Many others
*

35. Data Services
• Developers follow links before
ultimately consuming a Data Service
• API often still includes a version
• Projects / examples
- OData
-
-
PayPal API
GitHub v3
*

36. Interaction Services
• User-Agent let’s user follow links
• Available options and state are
described through links
*
• Projects / examples
-
-
IRIS
Restbucks
*

37. Shared Vocabulary
• Control navigation, state and
presentation
• Use a well defined media type /
shared vocabulary to control
certain aspects of validation &
rendering
• Projects / examples
- Restfulobjects, Apache ISIS
- Hydra, ALPS
*

38. Glory of Hypermedia
• Puts the user in total control
• Very well established; slowly
changing media types
• Projects / examples
- HTML5
- World Wide Web

39. Some Examples...

41. Why?
• Pragmatic
- ‘Practically ReSTful API’s’
• Human & Machine Friendly
• Reusable Patterns
- Resource Types
- Traits
• Open
http://raml.org/

42. What?

43. Demo

44. Demo
1. Design/Build your API
2. Document/Explore your API
3. Client/Server Contract for your API

45. Resource Interaction Model
(RIM)

46. Temenos Interaction Framework
• Of Interaction Framework (Hypermedia Server)…
- Reduce or eliminate client / server coupling
- Put the user in control (Object, Action)
- Reduce UI integration effort through mashup layer
*

47. Hypermedia Server
Temenos is donating a Java based
Hypermedia Server to the Open
Source Community
http://temenostech.temenos.com/
https://github.com/temenostech/IRIS
A project called IRIS; it has three
main goals:
1. To create web based services
according to RESTful constraints
2. Aggregate / mashup multiple
resource managers into a single
interaction service
3. Provide a language to describe
the interactions between these
resources

48. Resource Interaction Model (RIM)
• RIM language / example
-
-
-
-
Conditional links
Link relations
Auto transitions
Workflow
• HAL Browser
*

49. RIM Demo

50. Summary

51. Summary
• Who do you want to be in control?
• Human end user?
• More adaptive client.
• MediaType Selection
• Hypermedia controls
• Enrich with links vs. wrap
• There is value in just using links.
- Whatever maturity level you use.
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52. Thank You!