java on rails sv code camp 2014

Tim HobsonPrincipal Engineer, Chief Caffeine Officer @

Java on Rails - Using Spring Boot For Rapid Application Development

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About Me

Software Developer with a bad habit of leveraging frameworks

Not a fan of re-inventing wheels every project

Still believe you can move fast with good architecture

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Agenda

Why Spring Boot

Code

RAD

GOAL: Spring Boot has been demystified, looks promising, and you are inspired to give it a test drive.

Rapid Application Development

Rapid Application Development

Components, Frameworks and Platforms

The platform choice you make should enable you to move fast using the best of breed frameworks and

components

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Components

High-level software systems are built using components (or modules)

Leveraging existing components – saves time, – reduces opportunity for defects, – lets you focus on your value added work.

EG: Database connection pools, JSON and XML Parsers, Security libraries, HTTP Clients etc…

As an application developer, you are not being paid to build commodity services

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Choices, Choices…

97,613 packages49,603 packages

87,864 packages89,387 packages

27,580 packages

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Frameworks

Frameworks typically provide a collection of curated Components that work seamlessly togetherFrameworks provide implied (or explicit) patterns and practices to help maintain good architecture and maintainabilityFrameworks provide proven combinations of components in use for known use cases.

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Choices, Choices…

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PlatformsPlatforms go beyond software components and frameworks– Tooling– Deployment– Management– Testing– Maintenance– Versioning

Platforms are trying to create cohesive technology experiences for developers and businesses

Less for you to worry about, more time to focus on your domain

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Making Good ChoicesWhat do I need in the short term?

What might I need in the future?

How has the framework evolved, will it continue?

Are there enough people skilled in this framework?

Is the documentation and support good?

Is it an ordeal or a joy to work with?

There are more considerations than how easy “Hello World” is

Why Spring Boot?

?

A Cohesive Platform

The Spring Platform consists of components and frameworks that are useful in and of themselves, but are brought together through Boot in a way that lends itself to true RAD.

The framework is road-tested, and continues to be actively developed, keeping up with the latest technologies and patterns (Big Data, Reactive, HATEOS, Microservices, Cloud-deployed) and actively partnering with other OSS projects.

Spring Boot

What is it?– Dependency Management “Simplification”– Automatic Component Configuration– Cross-cutting infrastructure services– Deployment and Packaging alternatives

How does it do it?– “Starter Packs” of dependencies– Convention-based configuration– Production-ready services such as metrics, health,

app lifecycle.– Maven and Gradle plugins

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Dependency Management

Starter Packs bring together Spring and Third-Party dependencies needed to do something functionally:– Web– Data– Security– Test

Versioning controlled by a parent pom.xml

Include the starter packs you need, and go. <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-security</artifactId> </dependency>

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The Magic of Auto-Configuration

Configures based on what is in your classpathConfigures based on what @Beans are in place and which aren’tConfigures based on your application.yml or application.properties

@EnableAutoConfiguration

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So What’s So Great About That?EG: Writing a JSON Service that reads from a DB

Spring Boot Way

• Use/Include Spring Boot Starter Parent in pom/Gradle, add Spring Boot Starter Web and JPA

• Write Controller, Service, Repository Beans and Domain Objects

• Write Application class with @EnableAutoConfiguration

• Run as a Jar.

Old Spring Way• Configure Web Container• Create Web Project• Configure POM/Gradle/Ant dependencies

(with versions) build and and packaging (150 lines +)

• Configure web.xml with Spring context config files, dispatcher servlet, servlet mapping, Spring security Filter, etc..

• Write Controller, Service, Repository Beans and Domain Objects

• Configure *.xml files (Or annotated @Configuration Beans) with Bean definitions, View resolvers, content-negotiation, controller mapping, resource handling, error handlers, db pooling, connections, profiles, transactionmanager, jdbc templates or JPA config.

• Write code to import initial data from script

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Infrastructure Services

Audit

Metrics

Guages

Tracing

Configuration Views

Remote management via SSH

All Part of the Actuator Component

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Package and Deployment Alternatives

Package as a JAR– Choose embedded container (Jetty, Tomcat)– Configure container programmatically and/or via

application config– Run using java –jar

Package as a WAR– No web.xml required– Spring Dispatcher Servlet is auto-configured– Deploy to any Servlet container

Choices, Choices…

Do you already use Spring?

• Simplify your configuration

• Keep up with the latest version compatibility matrix

• Introduce Circuit Breaker patterns, distributed configuration, metrics and management APIs

• Get stuff done faster

Are you considering using Spring?• Skip the rewrite for the

JVM and write durable code!

• Leverage Dependency Injection, AOP, abstractions and integrations for major data stores, security standards, web standards and more.

• Fail to understand why it was known as “hard to use”.

Code

To-Boot

https://github.com/hoserdude/to-boot

git clone git@github.com:hoserdude/to-boot.git

Sample App to demonstrate all manner of things, cobbled together in about 2 days.

See README.md for instructions

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Things We Will Explore

Boostrapping (POM, Application.class)

Controllers (Routes, Marshalling, Resource Handling)

Views (Thymeleaf, AngularJS)

APIs (Swagger, DTO definition)

Security

Persistence (Config, Repositories, Domain Beans)

Application Structure, DI

Monitoring and Metrics

Deployment Options

Closing Thoughts

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Find Out More

• http://spring.io/projects

• http://spring.io/guides

THANK YOU

@hoserdude

@hoserdude

@hoserdude

hoserdude.com