Dev Inside A Docker Container With SSHFS

Many of you may have already discovered Docker, but have been put off using it due to the prospect of it killing your development cycle because you are rebuilding the container after every change.



We are going to address this by mounting the files directly within the container with SSHFS. This will allow us to make changes in our IDE or text editor, and see them take place immediately inside the container, removing the need to keep rebuilding.

Prerequisites

This tutorial assumes you already have a built container (or a way to build one) and a "project" consisting of a codebase, such as a website. It also assumes that your codebase is on a Linux host that you want to share from. I will be using an Ubuntu 14.04 container, but the theory should also apply to other Linux OS types.

If you are a Windows user, you could use Samba to sync to a linux host, and then use that one for this tutorial
    Start your container with the
    --privileged
    flag added to the
    run
    command. I don't know what options/switches you already have, but you just need to add this one to the list.
    Enter the running container. For this I use lxc-attach, but there is also a fantastic tool called docker-enter on github that you can use, which means you don't have to be running LXC for the container engine.
    Run
    apt-get install sshfs -y
    from inside the container.
    Create a folder where you wish to mount your codebase. This may want to replace any existing code that was imported into the container when it was built, in which case remove everything from inside that folder.
    Run the following command:
    sshfs -o allow_other $USER@$IP_OF_CODE_HOST:/full/path/to/codebase /path/to/mount
    The allow_other part is to allow other users within the container, such as www-data to be able to access the files
    That's it! Any changes you make to your codebase are immediately changed in the docker container. This allows you to use docker as an easy/quick way to get a development environment up (like Vagrant)!

1 comment:

  1. Very useful! I was missing the --privileged param... Very very good to know. Thanks!

    ReplyDelete