Docker Images

Creating a Dockerfile is a  declarative way to define the steps for building a docker image. A Dockerfile is a simple text-based script that contains the instructions for building a docker image, making it a reproducible and shareable artifact.

 

How to Create Docker Images?

  1. Create application directory:

    • Begin by creating a dedicated directory for the application. This Directory will contain both the app and Dockerfile.

  2. Create an empty Docker file:

    • In this directory, create an empty Dockerfile using a text/code editor.

      sudo nano Dockerfile
  3. Add instruction to the Dockerfile:

    • Define the steps for building the Docker image in the Dockerfile. For example:

      #Set parent image FROM ubuntu:22.04 as build #Set working directory in the container WORKDIR /app #Copy the local scripts and file to the container COPY lyrics.sh . # Install any needed packages RUN apt-get update && apt-get install -y \ curl && \ apt-get clean #Make scripts executable and run the script RUN chmod +x lyrics.sh && ./lyrics.sh
  4. Build and Tag Docker image:

    • Build the Docker image in the same directory (“.”) as the Dockerfile. Tagging the image helps organize it, especially if you plan to push it to a Docker repository. Use meaningful names or version numbers as tags.

      docker build -t imagename:youtag . docker tag imagename:youtag imagename:image1
  5. Log into docker account and push image to docker repository

    • Log into docker account:

    • Push image to a docker repo/registry. This will make it accessible to others: