The document discusses efficient Spring Data REST development. It defines REST as a software architectural style using HTTP to access and manipulate web resources represented as text. It describes the REST architectural style of using stateless operations like GET, POST, PUT, PATCH and DELETE on a resource's URL. It also discusses ETags for caching and conditional requests, generating REST events through annotated handlers or application listeners, using projections and excerpts for customized views of resources, and reactive access to repositories for streaming results.

1. Efficient Spring Data REST Development

2. 2
Who I Am

3. 3
What is REST (Representational State Transfer)?
 Software architectural style for creating RESTful web services
 Allow interoperability between Internet and computer
systems
 Requesting systems can access and manipulate web
resources represented as text
 Uses a set of well-known stateless operations

4. 4
The REST Architectural Style
 Not protocol-specific, most widely used: REST over HTTP
 The representation of the state can be JSON, XML, or HTML.
 The client uses the API to send the following to the server:
 The identifier (URL) of the resource
 The operation to perform on the resource (GET, POST,
PUT, PATCH, DELETE)

5. 5
What is an ETag?
 ETag (entity tag) - HTTP response header returned by an
HTTP/1.1 compliant web server used to determine change in
content at a given URL.
 Use ETags for caching and conditional requests.
 Efficiently controls data to be retrieved.

6. 6
Generating REST Events
 There are two ways of generating REST events:
 Writing an AnnotatedHandler
 Writing an ApplicationListener

7. 7
Projections and Excerpts
 Spring Data REST presents a default view of the domain
model you export.
 Sometimes you may need to alter the view of that model for
various reasons.
 Projections and excerpts serve as efficient and reduced views
of resources.

8. 8
Reactive Access to Repositories
 Efficiently retrieve results as a stream
 ReactiveCrudRepository
 R2dbcRepository

9. Thank you!