Now that we have the basics of Docker under our belt, let's look at the Dockerfile file we will be using as a template in this book.

Next, let's look at an example:

FROM golang:1.10
# The base image we want to use to build our docker image from. 
# Since this image is specialized for golang it will have GOPATH = /go                

ADD . /go/src/hello
# We copy files & folders from our system onto the docker image                       

RUN go install hello 
# Next we can create an executable binary for our project with the command,
'go install' ENV NAME Bob
# Environment variable NAME will be picked up by the program 'hello' 
and printed to console.ENTRYPOINT /go/bin/hello
# Command to execute when we start the container  
 
# EXPOSE 9000 
# Generally used for network applications. Allows us to connect to the
application running inside the container from host system's localhost.