If you are a developer, you probably have heard about Docker by now: Docker is the ideal platform to run applications in containers. Fine, but what are those containers? Containers are a lightweight virtualization technique providing us with lots of possibilities: thanks to them, we can ship applications faster; we can easily implement CI/CD (continuous integration and continuous delivery); we can set up development environments faster than ever; we can ensure parity between those development environments and our production servers; and much more. If you write code, if you deploy code, if you operate code, then I promise that containers are going to make your life easier.

But containers have been around for decades, and Docker was only released in 2013. So what's the big deal? Why is everybody so excited about Docker, if the technology behind it is more than ten years old?

Because the main innovation of Docker is not the technology. The main innovation of Docker is to make this technology available to every developer and sysadmin, very easily, without having to spend years of practice to become an expert, and without requiring to develop tons of custom tools.

I will share a secret with you: the really important thing is not Docker and containers. What is really important is to improve the quality of our software, reduce our development and deployment costs, release better, more reliable code, faster. It turns out that Docker is an insanely efficient way to achieve those goals. That's why it is so popular.

This book will teach you all you need to know to get started with Docker, and use it to build, ship, and run your applications. It will be your guide in the world of containers, and on the path to ship code better than you ever did before.

Jérôme Petazzoni

Docker Tinkerer Extraordinaire

A proposta deste livro é ajudá-lo a construir ambientes utilizando containers com a ferramenta que está revolucionando as empresas de tecnologia ao redor do mundo: vamos aprender e brincar bastante com o sensacional Docker!

De maneira leve e totalmente prática, vamos aprender desde o que é o Docker até a criação de um cluster Docker com diversos containers em execução! Sempre de forma prática, vamos abordar temas importantes para que consiga administrar ambientes que utilizam ou pretendam utilizar o Docker.

Inclusive, vamos aprender a montar dockerfiles personalizados para construção de imagens de containers, além de conhecer como melhor administrá-las.

Também veremos na prática como utilizar o Docker Machine para criação de hosts Docker, seja local ou na nuvem. Vamos criar um cluster utilizando o Swarm e aprender como escalar o nosso ambiente através do Compose.

Nesta segunda edição adicionamos muitas novidades, como o 'docker secret' e o 'docker stack', e atualizamos praticamente todo o restante do livro, visando torna-lo super atual e didático. Adicionamos mais exemplos práticos, para que sua experiência possa ser ainda mais agradável e proveitosa.