History

• Remote Procedure Calls (RPC, 1976)
  • ​CORBA (OMG)
  • Remote Method Invocation (RMI, Java)
  • DCOM (Microsoft)
• XML-RPC (1998) & SOAP (1999)
• REST (theory: 2000, practical usage: 2014)

SOAP Example: XML Schema/WSDL

SOAP Example: XML Request

REST is a architectural style for distributed systems

"Representational State Transfer"

people often mean  „RESTful HTTP“...

...when they say "REST"

Reusing the web´s infrastructure

• HTTP clients (Browsers)
• webservers
• parsers
• caching
• loadbalancing
• ssl
• ...

URI

URI = a Resources´ path and name, no Operation names!

In contrast to the RPC Styles!

Resources, Representations & Operations

Resources (URIs),                     http://api.devopenspace.de/users/1234

Representations  and              JSON, PDF, XML, HTML, ...

Operations on them                GET, PUT, POST, DELETE, ...

HTTP verbs

HTTP Statuscodes

GET          http://api.devopenspace.de/deleteUser?userId=1234

DELETE    http://api.devopenspace.de/users/1234

curl

Easiest tool to transfer data via REST!

...and it´s available nearly everywhere

-i include protocol headers in the output (H/F)
-k Ignore insecure certs
-X the HTTP method
-H add headers

Postman

Best REST GUI client, Chrome based

JSON Object Mapping

Jackson internally...

JSON-2-Java: User user = mapper.readValue(new File("user.json"), User.class);

Java-2-JSON: String json = mapper.writeValueAsString(user);

REST in Spring

Requests...

Requests with URI parametes...

Responses...

Testing with Spring

Testing with Spring

RestTemplate

Testing with Spring

MockMvc

Testing with Spring

REST-assured

github.com/jonashackt/spring-and-rest-basics

start with part2