Lukas Kahwe Smith | Liip AGsmith@pooteeweet.org | @lsmith

RESTing with Symfony2

Sunday, October 27, 13

Introduction to REpresentational State

Transfer

RESTing

Lukas Kahwe SmithSunday, October 27, 13

REST Maturity Model

RESTing

http://martinfowler.com/articles/richardsonMaturityModel.html

Lukas Kahwe SmithSunday, October 27, 13

Level 0: The Swamp of POX•HTTP as a tunneling mechanism•“Procedural” communication (RPC)•Single endpoint (per operation)

Lukas Kahwe Smith

RESTing

Sunday, October 27, 13

Level 1: Resources•Individual resources, i.e. URIs•“Object orientated” communication

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Level 2: HTTP Verbs•Client uses specific HTTP method•Server uses HTTP status codes

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Level 2: HTTP Methods

RESTing

Lukas Kahwe Smith

Method Safe? (★) Idempotent? (✦)

GET Yes YesHEAD Yes YesPOST No NoPUT No Yes

DELETE No Yes.. No No

(★) cacheable (✦) result independent on # of executions

Sunday, October 27, 13

RESTing

Lukas Kahwe Smith

Code range Description Example

1xx Information 100 - Continue2xx Successful 201 - Created

3xx Redirection 301 - Moved Permanently

4xx Client Error 404 - Not Found

5xx Server Error 501 - Not Implemented

Level 2: HTTP status codes

Sunday, October 27, 13

Level 3: Hypermedia Control•Service discovery via link relations•ATOM, HAL, JSON-LD, IANA Link Rel

RESTing

Lukas Kahwe SmithSunday, October 27, 13

RESTing

Hypertext As The Engine Of Application

State

Sunday, October 27, 13

H A T E O A S

RESTing

Sunday, October 27, 13

RMM vs REST vs real life

•RMM only covers a subset of REST•RMM Level 2 is what most developer think is sufficient for REST•RMM Level 3 is a REST precondition•RMM Level 3 makes URI formatting matter less

RESTing

Lukas Kahwe SmithSunday, October 27, 13

RMM vs REST vs real life

•REST is protocol independent•Few clients are prepared to leverage HATEOAS enabled REST APIs•Browsers are bad REST clients

RESTing

Lukas Kahwe SmithSunday, October 27, 13

URIs

•Identifies a resource•Independent of a specific format•URI “file extensions” != RESTful

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Media Types•Identifies a representation format•Custom types «application/vnd.»

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Lukas Kahwe Smith

Header Description

Content-Type HTTP message format

Accept HTTP response format preference

Accept-Encoding, Accept-Language, ..

HTTP response preference

Sunday, October 27, 13

Content Type Negotiation

•Finding appropriate response format•No standardized algorithm available•Apache mod_negotiation algorithm is well documented

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Content Type NegotiationAccept: application/json,application/xml;q=0.9,text/html;q=0.8,*/*;q=0.7

RESTing

Lukas Kahwe Smith

Priority Description

q=0.9 application/json or application/xml

q=0.8 text/html

q=0.7 */* (anything)

Sunday, October 27, 13

RESTing with Symfony2

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Bundles for a REST Server

•FOSRestBundle•JMSSerializerBundle•NelmioApiDocBundle•BazingaHateoasBundle ( FSCHateoasBundle )

•TemplatedUriBundle•LiipCacheControlBundle•FOSOAuthServerBundle

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Bundles for a REST Client

•FOSRestBundle•JMSSerializerBundle•HWIOAuthBundle•MisdGuzzleBundle

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Demo Time!

https://github.com/lsmith77/symfony-rest-edition/tree/2.3

RESTing

Lukas Kahwe SmithSunday, October 27, 13

Further reading•http://martinfowler.com/articles/richardsonMaturityModel.html•http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven•http://www.slideshare.net/Wombert/designing-http-interfaces-and-restful-web-services-dpc2012-20120608•http://williamdurand.fr/2012/08/02/rest-apis-with-symfony2-the-right-way/•http://knpuniversity.com/blog/what-the-rest•http://knpuniversity.com/blog/rest-revisited

RESTing

Lukas Kahwe SmithSunday, October 27, 13