What is 12 Factor App in DevOps?

The 12 Factor App is a methodology for building scalable, maintainable, and portable applications. It was created by Heroku co-founder Adam Wiggins in 2011 and has since become a standard for modern application development. In this blog post, we will discuss the 12 factors of the 12 Factor App and how they relate to DevOps.

1. Codebase

   The first factor of the 12 Factor App is to have a single codebase that is tracked in version control. This means that all developers are working on the same codebase, which makes it easier to collaborate and ensures that everyone is working with the latest version of the code. In DevOps, having a single codebase is important because it allows for easier automation of the build and deployment process.

2. Dependencies

   The second factor is to explicitly declare and isolate dependencies. This means that all dependencies should be declared in a manifest file, such as a requirements.txt file, and should be isolated from the application code. In DevOps, isolating dependencies makes it easier to manage the application's environment and ensures that the application can be easily deployed to different environments.

3. Config

   The third factor is to store configuration in the environment. This means that configuration variables, such as database credentials, should be stored in the environment rather than in the application code. In DevOps, storing configuration in the environment makes it easier to manage the application's configuration across different environments.

4. Backing Services

   The fourth factor is to treat backing services as attached resources. This means that services, such as databases and message queues, should be treated as attached resources rather than being bundled with the application code. In DevOps, treating backing services as attached resources makes it easier to manage the application's dependencies and ensures that the application can be easily deployed to different environments.

5. Build, Release, Run

   The fifth factor is to separate the build, release, and run stages. This means that the application should be built and tested in one environment, released to another environment, and then run in a production environment. In DevOps, separating the build, release, and run stages makes it easier to automate the deployment process and ensures that the application is tested and validated before being released to production.

6. Processes

   The sixth factor is to execute the application as one or more stateless processes. This means that the application should not rely on server state and should be able to scale horizontally. In DevOps, executing the application as stateless processes makes it easier to scale the application and ensures that the application can handle high traffic loads.

7. Port Binding

   The seventh factor is to export services via port binding. This means that the application should export services, such as HTTP endpoints, via port binding rather than relying on hard-coded URLs. In DevOps, exporting services via port binding makes it easier to manage the application's environment and ensures that the application can be easily deployed to different environments.

8. Concurrency

   The eighth factor is to scale out via the process model. This means that the application should be able to scale out horizontally by adding more stateless processes. In DevOps, scaling out via the process model makes it easier to handle high traffic loads and ensures that the application can handle failures.

9. Disposability

   The ninth factor is to maximize robustness with fast startup and graceful shutdown. This means that the application should be able to start up quickly and shut down gracefully. In DevOps, maximizing robustness with fast startup and graceful shutdown makes it easier to deploy and update the application without causing downtime.

10. Dev/prod parity

    The tenth factor is to keep development, staging, and production as similar as possible. This means that the development, staging, and production environments should be as similar as possible to avoid issues when deploying to production. In DevOps, keeping dev/prod parity makes it easier to deploy the application to production and ensures that the application behaves the same in all environments.

11. Logs

    The eleventh factor is to treat logs as event streams. This means that the application should log to stdout and stderr and that the logs should be treated as event streams. In DevOps, treating logs as event streams makes it easier to manage the application's logs and ensures that the logs can be easily analyzed and monitored.

12. Admin Processes

    The twelfth factor is to run admin/management tasks as one-off processes. This means that admin tasks, such as database migrations, should be run as one-off processes rather than being bundled with the application code. In DevOps, running admin/management tasks as one-off processes makes it easier to manage the application's environment and ensures that the application can be easily deployed to different environments.

In conclusion, the 12 Factor App is a methodology for building modern, scalable, and maintainable applications. In DevOps, the 12 Factor App is important because it provides a framework for building applications that can be easily deployed and managed in different environments. By following the 12 factors, developers and operations teams can work together to build applications that are reliable, scalable, and easy to manage.