What is a Dockerfile and how do I use it?

What is a Dockerfile and how do I use it?

A Dockerfile is a script that contains a series of instructions on how to build a Docker image. You can use it to automate the process of creating a containerized application.

Can you give me an example of a simple Dockerfile?

Sure! Here's a simple Dockerfile example:

FROM ubuntu:latest

RUN apt-get update && apt-get install -y python3

COPY . /app

WORKDIR /app

CMD ["python3", "app.py"]

This Dockerfile uses Ubuntu as a base image, installs Python, copies your app files, and sets the command to run your app.

How do I build an image from this Dockerfile?

You can build an image using the command docker build -t myapp . in the directory where your Dockerfile is located. Replace 'myapp' with your desired image name.

What are some common commands I can use in a Dockerfile?

Common commands include:

• FROM: specifies the base image.
• RUN: executes commands in the image.
• COPY: copies files from your host to the image.
• CMD: specifies the default command to run when the container starts.