touch Dockerfile

# syntax=docker/dockerfile:1

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

• FROM - Specifies the base image that the Docker image will be built upon. Choose a suitable base image that provides the necessary operating system and any pre-installed software your application needs.
• WORKDIR - Sets the working directory inside the container for any subsequent RUN, CMD, ENTRYPOINT, COPY, or ADD commands.
• COPY - Copies files or directories from the host machine into the container's filesystem.
• RUN - Executes commands in a new layer on top of the current image and commits the results. Use it to install required packages or dependencies.
• ENTRYPOINT - Configures a container that will run as an executable. It is used when you want the container to always run a command, and CMD provides arguments to that command.
• CMD - Provides default arguments for an ENTRYPOINT or executes a command if no ENTRYPOINT is defined.
• EXPOSE - Informs Docker that the container listens on the specified network at runtime.

Note: node:lts-alpine is a base image that comes with Node.js and the Yarn package manager pre-installed. It copies all of the source code into the image, installs the necessary dependencies, and starts the application.

docker build -t getting-started .

Note: docker build uses the Dockerfile to build a new image. After Docker downloaded the image, the instructions from the Dockerfile copied in your application and used yarn to install your application's dependencies. The CMD directive specifies the default command to run when starting a container from this image. The -t flag tags your image. Think of this as a human-readable name for the final image. getting-started is the name of the image and can be referred to when you run a container. The . at the end tells Docker that it should look for the Dockerfile in the current directory.

docker run -it --name my-alpine alpine sh

docker run -it --name my-ubuntu ubuntu:latest bash

docker run -it --name my-python python python

docker run -it --name my-node node node

docker run -it --name my-postgres postgres psql -U username

docker run -it --name my-redis redis

docker run -it --name my-mysql mysql

docker run -it --name my-nginx nginx

docker run -it --name my-busybox busybox

docker run -it --name my-memcached memchached

This creates a new container from an image.

docker run -it ubuntu:latest bash

docker run -it --name my-ubuntu ubuntu:latest bash

Note: -it connects your terminal directly to the inside of the Docker container so you can interact with it in real time.

This resumes an existing, stopped container.

docker start 98f05ff85c76

docker start my-ubuntu

docker ps # see all running containers

docker ps -a # see all containers

Note: ps stands for "process status."

This executes a container.

docker exec -it 98f05ff85c76 python

docker exec -it my-ubuntu bash

Copying from a Container

docker cp test-alpine:/app ~/Desktop

Copying to a Container

docker cp /path/to/local/file.txt container_name:/path/inside/container/

docker stop 4a9ba21ab079

docker stop my-ubuntu

Note: You can specify the CONTAINER ID or the NAME to stop the container.

docker rm 4a9ba21ab079

docker rm my-ubuntu