The Twelve-Factor App methodology is a methodology for building software-as-a-service applications. These best practices are designed to enable applications to be built with portability and resilience when deployed to the web.[1]
History
editThe methodology was drafted by developers at Heroku, a platform-as-a-service company, and was first presented by Adam Wiggins circa 2011.[1]
The Twelve Factors
edit# | Factor | Description |
---|---|---|
I | Codebase | There should be exactly one codebase for a deployed service with the codebase being used for many deployments. |
II | Dependencies | All dependencies should be declared, with no implicit reliance on system tools or libraries. |
III | Config | Configuration that varies between deployments should be stored in the environment. |
IV | Backing services | All backing services are treated as attached resources and attached and detached by the execution environment. |
V | Build, release, run | The delivery pipeline should strictly consist of build, release, run. |
VI | Processes | Applications should be deployed as one or more stateless processes with persisted data stored on a backing service. |
VII | Port binding | Self-contained services should make themselves available to other services by specified ports. |
VIII | Concurrency | Concurrency is advocated by scaling individual processes. |
IX | Disposability | Fast startup and shutdown are advocated for a more robust and resilient system. |
X | Dev/Prod parity | All environments should be as similar as possible. |
XI | Logs | Applications should produce logs as event streams and leave the execution environment to aggregate. |
XII | Admin Processes | Any needed admin tasks should be kept in source control and packaged with the application. |
Criticism and adaptation
editAn Nginx architect argued that the relevance of the Twelve-Factor app concept is somewhat specific to Heroku, while introducing their own (Nginx's) proposed architecture for microservices.[3] The twelve factors are however cited as a baseline from which to adapt or extend.[4]
References
edit- ^ a b c Hofmann, Michael; Schnabel, Erin; Stanley, Katherine (13 March 2017). Microservices Best Practices for Java. IBM Redbooks. pp. 2–3. ISBN 9780738442273.
- ^ Wiggins, Adam. "The Twelve-Factor App". Archived from the original on 13 June 2017. Retrieved 21 December 2017.
- ^ Horowitz, Ben (28 July 2016). "MRA, Part 5: Adapting the Twelve‑Factor App for Microservices". NGINX. Archived from the original on 22 December 2017. Retrieved 22 December 2017.
- ^ "Beyond the Twelve-Factor App - Exploring the DNA of Highly Scalable, Resilient Cloud Applications". O'Reilly. Retrieved 22 December 2017.