12 Factor Applications

Learn how to leverage the 12 Factor App methodology to deliver software that can be scaled, deployed and easily maintained.

Most importantly, learn to embed the methodology into your software development lifecycle to deliver better software.

Presented at forLoop Ibadan - Software Development LifeCycle event - March 17th, 2018

forLoop Ibadan is a child community of forLoop Africa. forLoop Africa is the fastest growing developer community in Africa.

Transcript

1. 12 Factor Applications Goke Obasa
2. About Me Lead Engr. DevOps / Mobile - Cotta & Cush Organiser - GDG Ibadan Founder / Editor - Continuous Bytes Ex Software Engr. - Releaf, Sanwo, Konga Tweets - @goke_
3. 12 Factor App • A programming language, service and cloud provider agnostic (independent) methodology for managing application lifecycle • Based on Heroku’s experience of developing, operating, and scaling of 100,000s of apps
4. Benefits of the 12 Factor App Approach • Minimizes divergence between environments • Easier deployment to the cloud - IAAS, PAAS and CAAS • Apps are easier to scale up without making significant changes to code and development processes • Easier onboarding of new members to the development team
5. The 12 Factors 1. Codebase 2. Dependencies 3. Config 4. Backing Services 5. Build, Release, Run 6. Processes 7. Port Binding 8. Concurrency 9. Disposability 10. Dev/prod Parity 11. Logs 12. Admin Process NB: Focus would be on the factors in bold
6. 1 - Codebase One codebase tracked in revision control, many deploys
7. Codebase Track your app source code in a Version Control System (VCS). Examples of VCS • Git • Subversion (SVN) • Mercurial
8. 1 - Codebase - Dos and Don’ts Dos • Use Single Codebase Don’ts • Use Multiple Codebases • Have Multiple Apps sharing Codebase
9. 2 - Dependencies Explicitly declare and isolate dependencies
10. Dependencies - Dos and Don’ts Dos • Use a Package Manager • Specify exact version • Version control lock file Don’ts • Rely on implicit existence of system-wide packages • Add library source to app codebase
11. Dependencies - Tools Language Dependency Manager PHP Composer JavaScript: NodeJS NPM, Yarn Java Maven, Gradle Ruby RubyGems
12. 3 - Config Store config in the environment
13. Config - Dos and Don’ts Dos • Store configuration as environment variables Don’ts • Hardcode configuration • Create different config file per environment
14. Accessing Environment Variables Language Code PHP getenv(<VAR_NAME>) JavaScript: NodeJS process.env.<VAR_NAME> Java System.getenv(<VAR_NAME>) Suggestion: Use dotenv library NB: Don’t push .env file to the code repository
15. 4 - Backing Services Treat backing services as attached resources
16. Backing Services A backing service is any service the app consumes over the network as part of its normal operation. Some Services • Datastores • Queuing Systems • Caching Systems • File Storage Services
17. Examples of Backing Services Service Examples Datastores MySQL, MongoDB, Postgres Queuing Systems ActiveMQ, RabbitMQ, Beanstalkd Caching Systems Redis, Memcached SMTP Services Sendgrid, Postmark
18. Backing Services - Dos and Don’ts Dos • Access services via a URL or other locator/credentials stored in the config Don’ts • Make a distinction between local and 3rd party services
19. 5 - Build, Release, Run Strictly separate build and run stages
20. Build, Release, Run Build Tools • Ant • Gradle • Gulp • Webpack Deployment Tools • Capistrano • Deployer • Fabric
21. Build, Release, Run - Steps Build - Converts a code repository into a build, using the code at the commit or tag specified by the deployment process. Release - Combines build from build stage with the deploys current config. Run - Executes the app by starting a process against the app's current release.
22. 6 - Processes Execute the app as one or more stateless processes
23. 7 - Port Binding Export services via port binding
24. 8 - Concurrency Scale out via the process model
25. 9 - Disposability Maximize robustness with fast startup and graceful shutdown
26. 10 - Dev / Prod Parity Keep development, staging, and production as similar as possible
27. Environments Explained • Development (Dev) - a developer making live edits to a local deploy of the app • Production (Prod) - a running deploy of the app accessed by end users
28. Challenges - Time Personnel Tools • Time - How long does it take to deploy • Personnel - Code is written by developers, DevOps engineers deploy it • Tools - Difference in stack of Dev and Prod
29. Dev / Prod Parity Dos • Keep deploy time as short as possible • Understand deployment and be closely involved • Ensure difference in Dev and Prod stack is very minimal Don’ts • Use lightweight backing services on Dev and heavyweight services on Prod
30. 11 - Logs Treat logs as event streams
31. 12 - Admin Processes Run admin/management tasks as one-off processes
32. A Quick Walkthrough of an Existing App App - Cotta&Cush Yii2 Base Project • Codebase - Code • Dependencies - Code • Config - Code • Backing Services - Code • Build, Release, Run - Code
33. References 12 Factor App Website - https://12factor.net/ Twelve-Factor Apps In node.js - https://peterlyons.com/twelve-factor-nodejs
34. Thank You