More Related Content
What's hot
What's hot (20)
Viewers also liked
Viewers also liked (20)
Similar to REST: The Most Misunderstood Software Architecture Ever
Similar to REST: The Most Misunderstood Software Architecture Ever (20)
Recently uploaded
Recently uploaded (20)
REST: The Most Misunderstood Software Architecture Ever
- 1. REST The Most Misunderstood Software Architecture Ever Martín Soto February 17, 2015
- 2. REST ● REpresentational State Transfer ● Roy Fielding, 2000 ● Deeply misunderstood! Many systems (mostly APIs) claim to be REST(ful), few really are. ● Abstraction of the World Wide Web.
- 4. Richardson’s REST Maturity Model http://martinfowler.com/articles/richardsonMaturityModel.html
- 5. Level 0: Plain, Old RPC http://martinfowler.com/articles/richardsonMaturityModel.html Plain, Old Remote Procedure Call (RPC)
- 6. Level 0: Remote Procedure Call (RPC) Caller Callee Procedure call Return value Caller execution Caller continues Procedure execution Network Corba DCOM java RMI ... HTTP Level 0
- 7. Level 0: RPC over HTTP ● Only one URL (e.g., http://example. com/api/v1) ● Procedure name and parameters passed as request payload. ● Return value returned as response.
- 8. Level 0: Example Amazon Elastic Computing Cloud (EC2) API
- 10. Level 1: Resources Company 1 Company 7 Company 33 User 4 User 28 User 13 User 5 User 62 User 44 User 99 User 63 Security policy 22 Security policy 85 http://api.com/companies/1 http://api.com/users/63 http://api.com/policies/85 http://api.com/companies/33 http://api.com/companies/7 http://api.com/users/63http://api.com/users/63 http://api.com/users/63 http://api.com/users/63 http://api.com/users/63 http://api.com/users/63 http://api.com/users/63 http://api.com/policies/85
- 11. Level 2: HTTP Verbs http://martinfowler.com/articles/richardsonMaturityModel.html
- 12. Level 2: HTTP Methods POST Create new resource (when POSTing to a collection) or execute especial operation on resource. GET Read the contents of resource (the resource representation) PUT Upload new resource contents replacing any previous contents. Also, create a resource if previously nonexistent. DELETE Delete the resource.
- 13. Level 2: Example Google Calendar API
- 16. Hypertext: HTML <HTML> <HEAD> <TITLE>Your Title Here</TITLE> </HEAD> <BODY BGCOLOR="FFFFFF"> <CENTER><IMG SRC="clouds.jpg" ALIGN=" BOTTOM"> </CENTER> <HR> <a href="http://somegreatsite.com">Link Name</a> is a link to another nifty site <H1>This is a Header</H1> <H2>This is a Medium Header</H2> Send me mail at <a href="mailto: support@yourcompany.com"> support@yourcompany.com</a>. <P> This is a new paragraph! <P> <B>This is a new paragraph!</B> <BR> <B><I>This is a new sentence without a paragraph break, in bold italics. </I></B> <HR> </BODY> </HTML>
- 19. HATEOAS Hypertext As The Engine of Application State
- 20. “What needs to be done to make the REST architectural style clear on the notion that hypertext is a constraint? In other words, if the engine of application state (and hence the API) is not being driven by hypertext, then it cannot be RESTful and cannot be a REST API. Period. Is there some broken manual somewhere that needs to be fixed? Roy Fielding http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
- 21. Programming with Hypermedia? http://martinfowler.com/articles/richardsonMaturityModel.html ??? ???
- 22. Hypermedia for Data APIs The Web <HTML> <HEAD> <TITLE>Your Title Here</TITLE> </HEAD> <BODY BGCOLOR="FFFFFF"> <CENTER><IMG SRC="clouds.jpg" ALIGN=" BOTTOM"> </CENTER> <HR> <a href="http://somegreatsite.com">Link Name</a> is a link to another nifty site <H1>This is a Header</H1> <H2>This is a Medium Header</H2> ... Data APIs ?
- 23. Example Putting Hypermedia to Good Use: Regional Privacy EU Web Service US Web Service CN Web Service
- 24. What we got from hypermedia API is independent of data location We were able to introduce this structure without breaking our API contract: Resource location becomes an implementation detail Data privacy becomes evident Customers can verify where their data is located by just looking at the requests their clients are running. All customers can be handled equally As long as you stick to a format, you can serve it from wherever you like and clients will handle it. API Versioning We can evolve the API by providing new fields pointing to new resources or formats. As long as the older fields are preserved, older clients will continue to work.
- 25. Example Federated Systems: Initial System Relational DB (MySQL)
- 26. Example Federated Systems: Fast Caching Relational DB (e.g., MySQL) Key-value Store (e.g., Redis)
- 27. Example Federated Systems: Microservices Microservice 1 Microservice 2 Microservice 3
- 28. Example Federated Systems: SaaS Customer 1 Customer 2 Customer 3 High-capacity cloud instance Low-capacity cloud instance In-premise, dedicated hardware
- 29. The (Not-So-Exiting) Present ● Many more APIs are going the hypermedia way GitHub, Nike, PayPal. ● Documentation for popular APIs still specifies URLs API providers make resource locations part of the API contract probably to appease programmers. ● Server frameworks and client libraries are getting better at hypermedia The improvement has been significant in the last two or three years.
- 30. Wrap Up ✓
- 31. Thanks! ...and welcome to the discussion Martín Soto @msotoweb donsoto@gmail.com http://martinsoto.co
- 32. Credits Presentation template by SlidesCarnival “Linked Web” picture courtesy Chris 73 / Wikimedia Commons, shared under Creative Commons Attribution-Share Alike 3.0. World map outline © Copyright Showeet.com, CC Attribution. For other credits, follow the links on the corresponding slides.