40 Days Of Kubernetes (2/40)

Day 2/40

How to Dockerize a Project

Install Docker Desktop

To get started with Docker on your local machine, download the Docker Desktop client:

• Docker Desktop Download

Getting Started with Docker

1. Clone a Sample Repository: You can either use your own project or clone a sample repository using the following command:

   git clone https://github.com/docker/getting-started-app.git

1. Navigate to the Project Directory: Change your working directory to the project folder:

   cd getting-started-app/

1. Create a Dockerfile: Inside the project directory, create a new file named Dockerfile:

   touch Dockerfile

1. Add Dockerfile Content: Open the Dockerfile in your preferred text editor and paste the following content:

   FROM node:18-alpine
   WORKDIR /app
   COPY . .
   RUN yarn install --production
   CMD ["node", "src/index.js"]
   EXPOSE 3000

This Dockerfile sets up a Node.js environment, installs dependencies, and specifies how to run the application.

1. Build the Docker Image: Build the Docker image from the Dockerfile using the following command:

   docker build -t day02-todo .

1. Verify the Docker Image: After building, check that the image was created and stored locally:

   docker images

Pushing the Docker Image to Docker Hub

1. Log In to Docker Hub: Authenticate with Docker Hub to push your image:

   docker login

1. Tag the Image: Tag your image to prepare it for pushing to a remote repository:

   docker tag day02-todo:latest username/new-reponame:tagname

1. Push the Image: Push the tagged image to Docker Hub:

   docker push username/new-reponame:tagname

Pulling and Running the Docker Image

1. Pull the Image in Another Environment: If you need to pull the image to a different environment, use:

   docker pull username/new-reponame:tagname

1. Run the Docker Container: Start the container and map the application to port 3000:

   docker run -dp 3000:3000 --name docker-container-name username/new-reponame:tagname

After this, your app should be accessible at http://localhost:3000.

Additional Docker Commands

• Access the Container Shell: To enter the running container, use:

  docker exec -it containername sh

or

  docker exec -it containerid sh

• View Container Logs: To check the logs from your container:

  docker logs containername

or

  docker logs containerid