Go Dev Environment with VsCode

The Goal of this image is to have a portable development environment. We ship this image with at least some of common dev tools I used The image contains the following software:

• Visual Studio Code [ 140 Mo ]
  • vscode-go
• Go 1.6.3 [ 320Mo ]
• git 2.7.4
• Emacs 24.5.1 + ruby 2.3.1 [ 189Mo ]
• Cloud Foundry Client 6.12 [25Mo]

Managing User

The best way to work with this tool is to bind-mount you $HOME inside the container so that you will be able to work on you file. I prefer not to work as root inside the container, so I will create you user inside the container at startup. You'll have to pass env variables MYUSERNAME, MYUID and MYGID so that when you edit files inside the container you'll have the sames rights as outside.

Get Image

Simply pull image from docker Hub

docker pull sebmoule/docker-vscode

Or build from source

make build

Running

There are 2 run Options :

Running the container with user's specified inside :

• make run

which runs : By running the following command you'll be able to start the container. I've added it to my bash aliases

alias vscode='docker rm vscode || true ; \
  docker run -dti \
    --net="host" \
    --name=vscode \
    -h vscode \
    -e DISPLAY=$DISPLAY \
    -e MYUID=$(id -u) \
    -e MYGID=$(id -g) \
    -e MYUSERNAME=$(id -un) \
    -e SSH_AUTH_SOCK=$SSH_AUTH_SOCK \
    -v $(dirname $SSH_AUTH_SOCK):$(dirname $SSH_AUTH_SOCK) \
    -v /tmp/.X11-unix:/tmp/.X11-unix \
    -v $HOME:$HOME \
    -w $HOME \
    sebmoule/docker-vscode'

with this alias, I remove and Recreate my container If not running. If my container vscode is already running, then it won't delete it neither create another one. I can just enter the container and start working.

Explain Parameters :

• Make Graphical application Works : share DISPLAY, X11 socket en local network
  • --net="host"
  • -e $DISPLAY
  • -v /tmp/.X11-unix:/tmp/.X11-unix
• Gives Home access and Create your own user inside the container :
  • -e MYUID=$(id -u) create user with your UID
  • -e MYGID=$(id -g) create group with your GID
  • -e MYUSERNAME=$(id -un) create user with you username
  • -v ${HOME}:${HOME} We bind-mount our HOME so that we can works with our files and access at least to :
    • ~/.bashrc ~/.Xauthority ~/.local/ .ssh ~/.gconf ~/.npm ~/.config/Code ~/.vscode ...
    • If you do so and bind-mount your home, your .bashrc Profile MUST set GOPATH and PATH so that it can resolve on /usr/local/go/bin.
    • that also mount the vscode preference directories .config and .vscode
  • -w $HOME set working directory to $HOME or whatever you like (your $GOPATH..)
• Gives access to your SSH-Agent (for ssh keys to connect to servers, git...)
  • -e SSH_AUTH_SOCK=$SSH_AUTH_SOCK
  • -v $(dirname $SSH_AUTH_SOCK):$(dirname $SSH_AUTH_SOCK)

Entrypoint

The entrypoint will create your user inside the container if you have passed the according Environment variables. It will also install some of tools for developping in Golang

The command will do the following:

• Create the user according to MYUID MYGID and MYUSERNAME
• save the IDE preferences into <your-HOME-dir>/.vscode
• mounts the GOPATH from your computer to the one in the container. This assumes you have a single directory. If you have multiple directories in your GOPATH, then see below how you can customize this to run correctly.

When bind-mounting you Home into the Container it will execture your .bashrc inside the container.

Configuring .bashrc

This Tool when bind-mounting your $HOME inside the container will source your HOME/.bashrc file. To work properly this file must at least contains :

...
#Add my PATH                                                                                                                                                                   
export GOPATH=~/go                                                                                                                                                             
PATH=$PATH:~/bin:~/.local/bin/:$GOPATH/bin/:/usr/local/go/bin/ 
...

In order to know when I work inside the container or on my box, I have differentiate my bash Prompt with different colors :

       # If we have MYUSERNAME we are in Docker                                                                                                                               
        if [ -z "$MYUSERNAME" ]; then                                                                                                                                          
            #I am on my box                                                                                                                                                    
            PS1="[\[\033[31m\]\u\[\033[00m\]@\[\033[35m\]\h\[\033[00m\]: \[\033[34m\]\w\[\033[00m\]]\[\033[00m\]$"                                                             
        else                                                                                                                                                                   
            #I am in the container                                                                                                                                             
            PS1="[\[\033[34m\]\u\[\033[00m\]@\[\033[32m\]\h-in-docker\[\033[00m\]: \[\033[35m\]\w\[\033[00m\]]\[\033[00m\]$"                                                   
        fi  

Demo