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![Fetch updated collection
GET /container1 HTTP/1.1
Host: example.org
Accept: application/ld+json, application/json, */*;q=0.1
Request
GET
container1
member1
member2
member3
member4
http://example.org
Removed HTTP headers to save some space
Link: </cat.jsonld>; rel=“context”
{
"@id" : "http://example.org/container1",
"@type" : ”http://www.w3c.org/ns/ldp#Container",
"title" : ”Product catalog",
"member" : [ "member2", "member1", "member3", "member4" ]
}
Response](https://image.slidesharecdn.com/restmeetssemweb-141008193914-conversion-gate02/75/REST-meets-Semantic-Web-24-2048.jpg)
Uploaded bySteve Speicher
REST meets Semantic Web
This document discusses using semantic web technologies with REST APIs. It provides a case study of calculating issue close times from GitHub and Jira APIs. The code starts simply but gets more complex to handle different API representations. Adding semantics through common schemas helps parse issues into a uniform object to simplify the code. The document advocates for combining REST, hypermedia, and semantics for understanding and discovery.
REST meets Semantic Web
- 1. REST meets SemanticWeb by Steve Speicher @sspeiche ©Steve Speicher @sspeiche. All rights reserved. REST meets Semantic Web
- 2. Areas to explore… RESTperts Case Study Semantic What? BEvERages
- 3. Look at areal cases Case Study (show me) “Without data you’re just another person with an opinion” W. Edwards Deming
- 4. Case Study Problem: From some known issues, find out how long they have been open per assignee. Oh, based on GitHub issues.
- 5. GitHub Issues CaseStudy There’s an API for that… GET /repos/:owner/:repo/issues/:number
- 6. Case Study $curlhttps://api.github.com/repos/w3c/ldp-testsuite/issues/17 { "created_at": "2014-05-27T20:06:49Z", "updated_at": "2014-06-30T01:37:00Z", "closed_at": "2014-06-30T01:37:00Z", "state": "closed", "assignee": { "login": "sspeiche", "id": 727196, "avatar_url": "https://avatars.githubusercontent.com/u/727196?v=2", "url": "https://api.github.com/users/sspeiche", "followers_url": "https://api.github.com/users/sspeiche/followers", "following_url": "https://api.github.com/users/sspeiche/following{/other_user}", "gists_url": "https://api.github.com/users/sspeiche/gists{/gist_id}” }, }
- 7. Case Study if(val.state == "closed” && val.assignee.login == assignee) { computeCloseTime(assignee, val.closed_at, val.created_at); } Simple enough code, right?
- 8.
- 9. Case Study $curlhttps://issues.apache.org/jira/rest/api/2/issue/IO-147 { "created": "2007-12-18T13:04:55.320+0000”, "updated": "2008-08-22T07:36:50.877+0000", "resolutiondate": "2008-01-04T12:32:51.403+0000”, "customfield_12310220": "2007-12-18 18:19:12.648", "status": { "self": "https://issues.apache.org/jira/rest/api/2/status/6", "name": "Closed", "id": "6", }, "assignee": { "self": "https://issues.apache.org/jira/rest/api/2/user?username=steves", "name": ”steves", "emailAddress": ”steves at apache dot org", "displayName": ”Steve S” }, }
- 10. Case Study if(val.state == "closed” && val.assignee.login == assignee) { computeCloseTime(assignee, val.closed_at, val.created_at); } else if (val.status.name == "Closed” && val.assignee.name == assignee) { computeCloseTime(assignee, val.resolutiondate, val.created); } Code becomes this…. …not so simple anymore, but wait!
- 11.
- 12. Case Study ©SteveSpeicher @sspeiche. All rights reserved. REST meets Semantic Web
- 13. Case Study if(val.state == "closed” && val.assignee.login == assignee) { computeCloseTime(assignee, val.closed_at, val.created_at); } else if (val.status.name == "Closed” && val.assignee.name == assignee) { computeCloseTime(assignee, val.resolutiondate, val.created); } else if (val.issueState != “Opened” && val.owner.login.id == assignee) { computeCloseTime(assignee, convertDateTime(val.end.date, val.end.time), convertDateTime(val.start.date, val.start.time)); } else if (val.status != “Opened” && val.status != “InProgress” && val.status != “InReview” && matchAssignee(val.assignee.mbox, assignee)) { computeCloseTime(assignee, val.lastUpdated, val.creationDate); } THEN code becomes this….
- 14. Case Study $curlhttps://magical.unicorns.org/nonissue4 Link: </issue.jsonld>; rel=“context” { "created": "2008-08-18T13:04:55.320+0000”, "updated": "2008-09-04T12:32:51.403+0000", ”closed” : "2008-09-04T12:32:51.403+0000”, “status” : “closed”, "assignee": { ”@id” : "https://stevespeicher.me", ”login” : ”sspeiche", ”mbox” : ”steves@unicorns.org", ”title": ”Steve S” }, } Ideal
- 15. Case Study Thisinitial code sample could be the var issue = parseIssue(val); if (issue.status == “closed” && issue.assignee.login == assignee) { computeCloseTime(assignee, issue.closed, issue.created); } complex case too…
- 16. Case Study varissue = parseIssue(val); if (issue.closed && issue.assignee.login == assignee) { computeCloseTime(assignee, issue.closed, issue.created); } …and even simpler
- 17. PRACTICAL APPLICATIONS OFSEMANTICS IN RETAIL A YEAR OF EXPERIMENTATION Jay Myers, Best Buy @jaymyers
- 18. COMMON DATA FLOWINTO CMS/ PIM Data Source(s) PIM/ CMS with schema Accepted data Discarded data RDBMS
- 19. COMPLETE DATA +SEMANTICS = DISCOVERY + +
- 20. CONVERSION 11x 9x5x “Stocking Stuffers” Valentine’s Day St Patrick’s Day * vs. standard site conversion
- 21. (web services) Whatis REST? Ask the… REST RESTafarians, RESTperts, …
- 22. REST (web services) Resource GET POST PUT DELETE Collection URI fetch create http://ex.com/resources element create / replace rm * Element URI http://ex.com/resources/item17 fetch open create / replace rm
- 23. Create and add POST /container1 HTTP/1.1 Host: example.org Content-length: 324 Link: <http://schema.org/context.jsonld>; rel=“context” { ”@type" : ”http://schema.org/Product", ”name" : ”White microwave", ”productId" : ”w2134" } HTTP/1.1 201 CREATED Content-Location: http://example.org/container1/member4 Response Request POST container1 member1 member2 member3 +member4 http://example.org
- 24. Fetch updated collection GET /container1 HTTP/1.1 Host: example.org Accept: application/ld+json, application/json, */*;q=0.1 Request GET container1 member1 member2 member3 member4 http://example.org Removed HTTP headers to save some space Link: </cat.jsonld>; rel=“context” { "@id" : "http://example.org/container1", "@type" : ”http://www.w3c.org/ns/ldp#Container", "title" : ”Product catalog", "member" : [ "member2", "member1", "member3", "member4" ] } Response
- 25. Semantics (understanding) Semantics So I have some representation, now what?
- 26.
- 27. <a href=“/item47” type=“product”>ProductA</a> or “productId” : “w2134” “name” : “Product B” REST What about the hypermedia?
- 28. Semantics Are wetalking about the same thing? “productId” : “w2134” or “product” : “http://ex.com/resources/item47”
- 29. Semantics What arewe talking about? “productId” : “w2134” or “@type” : “http://schema.org/Product” “isCatalog” : true or “@type” : “http://www.w3.org/ns/ldp#Container”
- 30. Did a smallpart of Roy T. Fielding die? What went wrong? Wrap it up
- 31. Discovery Docs Wrapit up URL templates - https://tools.ietf.org/html/rfc6570 JSON-Home - http://tools.ietf.org/html/draft-nottingham-json-home-03 stacker.io - http://petstore.swagger.wordnik.com/
- 32. © your companyname. All rights reserved. Title of your presentation