Docker for Serverless Applications

Building a container image

We use Docker to prepare our software and its execution environment by packing them onto a file system. We call this step building a container image. OK, let's do this. We will build our own version of an NGINX server on Ubuntu, my-nginx, as a Docker image. Please note that the terms container image and Docker image will be used interchangeably throughout this book.

We create a directory called my-nginx and change to it:

$ mkdir my-nginx$ cd my-nginx

Then, we create a file named Dockerfile with the following content:

FROM ubuntuRUN apt-get update && apt-get install -y nginxEXPOSE 80ENTRYPOINT ["nginx", "-g", "daemon off;"]

We will explain the contents of Dockerfile line by line:

• First, it says that we want to use ...