Overview of the Ratpack web framework. Source for the talk (including demo apps) here: https://github.com/ratpack/ratpack-talks/tree/master/talks/cdjdn

1. Intro to Ratpack
2015-01-22

2. About Me
David M. Carr
Member of Ratpack core team
Software Architect with CommerceHub
Email: david@carrclan.us
Twitter: @varzof
GitHub: davidmc24

3. CommerceHub is Hiring!
Software Engineer (multiple openings)
Senior Software Engineer (multiple openings)
QA Engineer
Other positions

4. Overview

5. What is Ratpack NOT?
Servlet-based
Groovy-based
Just a Sinatra clone
At one point, it was all of these things… but now it’s so much more.

6. What is Ratpack?
Ratpack is a set of Java libraries that facilitate fast, efficient, evolvable and well
tested HTTP applications.
It is built on the highly performant and efficient Netty event-driven networking
engine.
Ratpack focuses on allowing HTTP applications to be efficient, modular, adaptive
to new requirements and technologies, and well-tested over time.
Ratpack is a new project, but stands on the shoulders of well-established
technologies and is built by developers with substantial experience in web
application frameworks and tooling. It is currently pre-1.0 but under very active
development.

7. Features
A full-stack, high throughput, non-blocking web framework
Built entirely on Java 8
Emphasis on Performance and Efficiency
Both in runtime and development experience
Hot-reloading available during development time
Emphasis on developer testing, especially functional and integration

8. Core Dependencies
Minimum Java 8; allows deep support for Lambda Expressions
Netty for high-performance event-driven networking
Guava for common functionality missing from Java’s standard library
Reactive Streams for standardized asynchronous stream processing

9. Modularity
A set of composable libraries for building un-opinionated, rich web apps
Pick-and-choose what aspects of the framework you want
No lock-in to a single way of doing things
No plugins; modularity through dependency-injected modules
DI supported via a abstractionRegistry
Out-of-the-box integration with Guice (preferred) and Spring

10. Current Modules
Asynch: reactor, rx
Authentication: pac4j
Build/Packaging: gradle
Common: config, session
Database: h2, hikari
Dependency Injection: guice, spring-boot
JSON: jackson
Language: groovy
Reliability: hystrix, codehale-metrics, newrelic
Templates: handlebars, thymeleaf, groovy
Testing: test, groovy-test

11. Gradle Java Build
buildscript {
repositories { jcenter() }
dependencies {
classpath "io.ratpack:ratpack-gradle:0.9.11"
}
}
apply plugin: "io.ratpack.ratpack-java"
repositories { jcenter() }
mainClassName = "App"

12. Gradle Groovy Build
buildscript {
repositories { jcenter() }
dependencies {
classpath "io.ratpack:ratpack-gradle:0.9.11"
}
}
apply plugin: "io.ratpack.ratpack-groovy"
repositories { jcenter() }
mainClassName = "App"

13. Groovy Support
Specialized support for writing apps in Groovy
Why Groovy?
Similar performance to Java using Invoke Dynamic or Static Compilation
Supports static compilation, compile-time type checking, dynamic typing
Can pick-and-choose between these modes depending on the use case
Supports a rich DSL with support for type checking via @DelegatesTo
Rendering based on andMarkupTemplateEngine Script

14. Architecture
Assemble a RatpackServer.Definition
Contains a ; defines settings required to start serverServerConfig
Contains a ; DI abstraction, stores objects by typeRegistry
Contains the root Handler
Use the definition to build a that can then be started.RatpackServer
No need for a container; batteries included.

15. Handlers
All request processing is done via composition of sHandler
Each in the chain is asked to respond to a request until one does.Handler
Similar to a combination of and .Servlet Filter
A handler can:
Respond to the request
Delegate to the “next” Handler
“Insert” s into the chain and immediately delegate to themHandler
Handlers operate on a which represents the current state ofContext
processing a request

16. 0.9.13 Preview
Will be released on Feb. 1
We currently release on the first of every month
Two headline features:
New launch approach
New config module

17. Demos!

18. Questions?