1. Creating 3rd Generation
Web APIs with Hydra
Markus Lanthaler
Graz University ofTechnology

3. Level 0:The Swamp of POX
Level 1: Resources
Level 2: HTTPVerbs
Level 3: Hypermedia Controls

4. Using Web APIs is still challenging

5. - Layered system

6. Result: tightly coupled & brittle systems

7. REST + Linked Data: a match made!?

8. Semaphobia!?

11. Resource
Link
Form
Class
Operation
Hydra

13. {
"id": "cso29ax",
"title": "WWW2013",
"description": "Presentation for dev track",
"is_open": true,
"created_at": "2012-11-26T04:49:44Z"
}
http://example.com/issues/cso29ax
http://example.com/issue/{id}/comments/

14. {
"id": "cso29ax",
"title": "WWW2013",
"description": "Presentation for dev track",
"is_open": true,
"created_at": "2012-11-26T04:49:44Z",
"comments": "/issues/cso29ax/comments/"
}
http://example.com/issues/cso29ax

15. {
"@context": "/ctx/context.jsonld",
"id": "cso29ax",
"title": "WWW2013",
"description": "Presentation for dev track",
"is_open": true,
"created_at": "2012-11-26T04:49:44Z",
"comments": "/issues/cso29ax/comments/"
}
http://example.com/issues/cso29ax

16. {
"@context": {
...
"is_open": "http://example.com/vocab#isOpen",
"comments": {
"@id": "http://example.com/vocab#comments",
"@type": "@id"
}
}
}
http://example.com/ctx/context.jsonld

17. {
"@context": "/ctx/context.jsonld",
"id": "cso29ax",
"title": "WWW2013",
"description": "Presentation for dev track",
"is_open": true,
"created_at": "2012-11-26T04:49:44Z",
"comments": "/issues/cso29ax/comments/"
}
http://example.com/issues/cso29ax
{
"@id": "#comments",
"@type": "hydra:Link",
...
}

18. {
"@id": "#comments",
"@type": "hydra:Link",
"supportedOperations": [
{
"@id": "#create-comment",
"@type": "hydra:CreateResourceOperation",
"label": "Creates a new comment",
"method": "POST",
"expects": "#Comment",
"returns": "#Comment"
}
]
}

19. {
"@id": "#Comment",
"@type": "hydra:Class",
"supportedProperties": [
{
"property": "#text",
"required": true,
"readonly": false,
"writeonly": false
}
]
}

21. Hydra Console

26. © 2013, Markus Lanthaler. Some Rights Reserved.
http://creativecommons.org/licenses/by-nc-sa/3.0/
Thank You

27. Questions?
Markus Lanthaler
http://www.markus-lanthaler.com
@MarkusLanthaler
mail@markus-lanthaler.com

28. Image Credits
(1) http://www.flickr.com/photos/joeshlabotnik/3707230247/
(2) http://onlyhdwallpapers.com/high-definition-wallpaper/903850/
(4) http://www.flickr.com/photos/kaptainkobold/3203311346/
(6) http://www.flickr.com/photos/joyoflife/1570126182/
(8) http://en.wikipedia.org/wiki/The_Scream
(9) http://www.vonwong.com/ (with permission)