This document discusses best practices for deploying Java applications based on the 12 Factor App methodology. The 12 factors are codebase, dependencies, configuration, backing services, build and release, processes, port binding, concurrency, disposability, development and production parity, logs, and admin processes. Adhering to practices like separating configuration from code, making processes disposable and reproducible, and running admin tasks separately can improve an application's scalability, maintainability, and portability. The document argues that by adopting this methodology, Java applications can avoid common problems and perform as well as applications in other languages.

1. 12 Factor App
Best Practices for JVM Deployment

2. 12 Factor App
Best Practices for JVM Deployment
Java doesn’t suck
when you do things this way

3. XML sucks

4. 10 page wikis to set up your app suck

5. Incongruent environments suck
DEV ≠ PROD

6. Apps that take more than 30 seconds
to start up suck

7. Recompiling your entire codebase
after fixing a typo sucks

8. Monolithic apps suck

9. The Java language sucks

10. But Java doesn’t suck

11. What does modern Java
development look like?

12. Joe Kutner
@codefinger
JVM Languages Owner
@Heroku
Joe Kutner

13. 12 Factor App
a methodology
Scalability
Maintainability
Portability

14. 12 Factor App
a methodology
Continuous
Delivery

15. 12 Factor App
a methodology
Sleeping
at
Night

16. Continuous Delivery
Sleep

17. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

18. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

19. Graceful shutdown
Quick startup
Resilience to failure
| Disposability |

20. | Disposability |
Application Servers are
not disposable

21. Application Servers are
not disposable
| Disposability |

22. | Disposability |
Microservices are
disposable

23. | Disposability |
Easy to replace
Decoupled from
external infrastructure
Easy to modify

25. | Disposability |
Microservices
Java
Groovy
Scala
Clojure
Scala Scala

26. Standalone ➤ Disposable
| Disposability |

27. Bootable ➤ Disposable
| Disposability |

28. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

29. dev
sqlite
postgres
stage
mysql
postgres
prod
postgres
postgres
=
≠
=
=
≠
=
| Disposable | Parity |

30. dev
jetty
jetty
stage
tomcat
jetty
prod
jboss
jetty
=
≠
=
=
≠
=
| Disposable | Parity |

31. | Disposable | Parity |
dev
jetty
{}
stage
tomcat
{}
prod
jboss
{}
=
≠
=
=
≠
=

32. .war
Traditional JVM Deployment

33. .jar
Modern JVM Deployment

34. Reproducible ➤ Parity
| Disposable | Parity |

35. Reproducible ➤ Disposable
| Disposable | Parity |

36. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

37. Configuration belongs in the environment,
not in the application
Configuration should be strictly
separated from code
| Disposable | Parity | Config |

38. Linux
Tomcat
WAR
server.xml
context.xml
web.xml
/etc/...
| Disposable | Parity | Config |

39. Environment
Java Application
PATH
DATABASE_URL
AWS_ACCESS_TOKEN
JAVA_OPTS
| Disposable | Parity | Config |

40. Containerless ➤ Separation
| Disposable | Parity | Config |

41. Containerless ➤ Parity
| Disposable | Parity | Config |

42. Containerless ➤ Disposable
| Disposable | Parity | Config |

43. Containerless ➤ 12 Factor App
| Disposable | Parity | Config |

44. Containerless Containerless Containerless
| Disposable | Parity | Config |

45. Dropwizard

46. @Configuration
@EnableAutoConfiguration
@ComponentScan
public class Main {
public static void main(String[] args) {
SpringApplication.run(Main.class, args);
}
}

47. import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.*;
public class Main {
public static void main(String[] args) throws Exception {
Server server = new Server();
ServletContextHandler context = new ServletContextHandler(
ServletContextHandler.SESSIONS);
context.setContextPath("/");
server.setHandler(context);
context.addServlet(new ServletHolder(new App()), "/*");
server.start();
server.join();
}
}

48. (defn -main [& [port]]
(jetty/run-jetty (site #'app) {:port port :join? false}))

49. // Play example does not require any code

50. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

51. | Disposable | Parity | Config | Concurrency |
Scale Up
Scale Out

52. | Disposable | Parity | Config | Concurrency |
web.1
web.2
worker.1 clock.1
Workload Diversity
NumberofProcesses
worker.2
worker.3

53. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

54. | Disposable | Parity | Config | Concurrency | Admin |
Admin tasks should be
run in isolated processes

55. web1
web2
web3
admin
| Disposable | Parity | Config | Concurrency | Admin |

56. The 12 Factors
• Codebase
• Dependencies
• Config
• Backing services
• Build, release, run
• Processes
• Port binding
• Concurrency
• Disposability
• Dev/prod parity
• Logs
• Admin processes

57. TODO
List

58. Install the JDK
Three Steps to Setup Your App
Clone the SCM repo
Run the app

59. Get it under 30 seconds
Time your app’s startup
Get a stopwatch
Make Your App Startup Quick

60. Deploy or Scale Your App in One Step
Handle requests
Deploy the app
Provision a new environment

61. http://12factor.net

62. Java Doesn’t Suck

63. Java Doesn’t Suck
(if you use it the right way)

64. Joe Kutner
@codefinger
JVM Languages Owner
@Heroku
http://www.slideshare.net/jkutner/jdays-2015