backpack

This repository contains the packer configuration to build a base box for use with our box.

⚠️ NOTICE ⚠️

This repository is currently experimental. It hasn't been tested with utilities for working with firmware onsite.

What is packer?

Packer is a program that takes in some configuration and outputs a machine image. This machine image can be loaded into virtualbox with vagrant. This toolchain of packer -> vagrant -> virtualbox allows us to provide a standardized development environment, regardless of host OS.

It works in three steps:

1. Execute builders. This is basically the initial ubuntu configuration, which is defined in the builders section of backpack.json and http/preseed.cfg. You'll (hopefully) never need to touch these.
2. Run provisioners. These are defined in the provisioners section of backpack.json. There are a number of provisioning tools you might see in industry or in job descriptions like chef, ansible, and puppet. However, we opt for simple shell scripts to do the provisioning because they're easier to understand and update without learning new tools. These scripts live in scripts, and are probably the only things you'll need to touch in this repo.
3. Run post-processors. This is the post-processors section of backpack.json, and is what outputs the final vagrant-compatible image.

Philosophy

Packer configuration is pretty complex already, so this repo is designed to make it as easy as possible to add to the "backpack". Keeping things in here makes for a more smooth onboarding and setup process for new team members. If adding extra functionality, make sure to add comments and keep things neat for future generations.

Dependencies

In order to work with packer, you'll need:

• ruby
• packer
• virtualbox However, in order to properly test and release, it's highly recommended you have the uwmidsun box set up in order to properly test your changes.

Adding functionality

First, set up a brand new box to test your changes with. Run your installation commands as you would, but with sudo. As an example, if you wanted to add foobar:

sudo apt-get -y install foobar

After you've made sure foobar is working correctly, add the same commands to the appropriate setup script without the sudo, with a comment:

...
#Install foobar
apt-get -y install foobar
...

If you're adding significant steps, consider adding an additional setup script by adding its name to the scripts section of backpack.json, then creating the new script in the scripts directory.

Once you're happy with your changes, pack the new box with:

packer build backpack.json

This will take a really long time, potentially up to 20 minutes. The process may appear to be stuck at:

==> virtualbox-iso: Waiting for SSH to become available...

This is normal. Give it at least 10 minutes just at this step before deciding the run's a failure.

On success, something along the lines of the following should appear:

==> virtualbox-iso (vagrant): Creating Vagrant box for 'virtualbox' provider
    virtualbox-iso (vagrant): Copying from artifact: output-virtualbox-iso/packer-ubuntu-18.04-amd64-disk001.vmdk
    virtualbox-iso (vagrant): Copying from artifact: output-virtualbox-iso/packer-ubuntu-18.04-amd64.ovf
    virtualbox-iso (vagrant): Renaming the OVF to box.ovf...
    virtualbox-iso (vagrant): Compressing: Vagrantfile
    virtualbox-iso (vagrant): Compressing: box.ovf
    virtualbox-iso (vagrant): Compressing: metadata.json
    virtualbox-iso (vagrant): Compressing: packer-ubuntu-18.04-amd64-disk001.vmdk
Build 'virtualbox-iso' finished after 15 minutes 13 seconds.

This should be accompanied by the creation of the file backpack.box in this directory. Release this as a new version here, bumping the minor or major version number as appropriate. Finally, open a PR to bump the backpack version in the box repo by changing the line that looks something like:

config.vm.box_url = "https://github.com/uw-midsun/box/releases/download/v1.1.0/backpack.box"