Best practices for writing Dockerfiles

1. As a base image, use official images. And whenever it is possible, use Alpine images as a base image.
2. Don’t copy unnecessary files and folders or install/use unnecessary packages of software.
3. Running a container process as root is not recommended. As a non-root user, launch the application container process.
4. Reduce the number of image layers as much as you can.
5. Wherever possible, try to use multi-stage Docker files to reduce the size of the image.

Pre-requsites: Docker,Dockerfile

A Dockerfile is a script that uses the Docker platform to generate containers automatically. It is essentially a text document that contains all the instructions that a user may use to create an image from the command line. The Docker platform is a Linux-based platform that allows developers to create and execute containers, self-contained programs, and systems that are independent of the underlying infrastructure. Docker, which is based on the Linux kernel’s resource isolation capabilities, allows developers and system administrators to transfer programs across multiple systems and machines by executing them within containers.

Docker containers may operate on any Linux host thanks to Dockerfiles. Docker images are used to construct container environments for applications, and they may be produced manually or automatically using Dockerfiles. Docker containers can execute Linux and Windows apps. Developers may use Dockerfiles to construct an automated container build that steps through a series of command-line instructions. Docker containerization is essentially virtualization at the operating system level. Without the startup overhead of virtual machines, several independent containers can run within a single Linux instance.

Dockerfiles provide business applications with more flexibility and mobility. Dockerfiles are used by IT companies to bundle programs and their dependencies in a virtual container that may operate on bare metal, in public or private clouds, or on-premises. Numerous apps, worker tasks, and other activities can operate independently on a single physical computer or across multiple virtual machines using containers. Kubernetes is an open-source solution for automating the management and orchestration of Dockerfile-based containerized applications.