Working with Docker Images and Containers

Now that Docker is installed, let's learn the commands you'll use every day.

#Pulling an Image

docker pull nginx:latest

#Running a Container

docker run -d -p 8080:80 --name my-nginx nginx:latest

This runs Nginx in the background (-d) and maps port 8080 on your host to port 80 in the container.

#Listing Containers

docker ps          # running containers
docker ps -a       # all containers, including stopped

#Stopping and Removing Containers

docker stop my-nginx
docker rm my-nginx

#Viewing Logs

docker logs -f my-nginx

#Building Your Own Image

A minimal Dockerfile for a Node.js app looks like this:

FROM node:20-alpine
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
CMD ["node", "index.js"]

Build and run it with:

docker build -t my-node-app .
docker run -p 3000:3000 my-node-app

Next, we'll bring multiple containers together with Docker Compose.