pi-gen-utils

Utility scripts to make it easy to develop custom RPi images using the pi-gen system (https://github.com/RPi-Distro/pi-gen )

Pi-gen is incredibly useful as way to create images with precisely the packages and features required for a task. However it is conceptually wrong to have the custom scripts developed in the pi-gen directory structure. Firstly this causes issues as and when pi-gen itself is updated and secondly it is hard to identify the changed files and therefore what changes have been made for your project.

With these utilities you can have your files in a single directory and have them copied into the pi-gen directory to create the image. The original files are then stored in a backup directory and are restored between builds so as to keep the pi-gen directory tree clean.

In the single directory the relatively complex directory structure of pi-gen is maintained but the '/'s are replaced by '_'. If a file needs an underscore in the name then it should be doubled. e.g. stage3/SKIP_IMAGES is called stage3_SKIP__IMAGES

e.g. a project that creates a raspbian-lite image with different base packages might have the following files in its directory:

config
stage0_00-configure-apt_00-run.sh
stage2_01-sys-tweaks_00-packages
stage2_01-sys-tweaks_01-run.sh
stage2_01-sys-tweaks_files_customfile.txt
stage3_SKIP
stage4_SKIP
stage4_SKIP__IMAGES
stage5_SKIP
stage5_SKIP__IMAGES

these would then be copied to the pi-gen directory as follows:

config
stage0/00-configure-apt/00-run.sh
stage2/01-sys-tweaks/00-packages
stage2/01-sys-tweaks/01-run.sh
stage2/01-sys-tweaks/files/customfile.txt
stage3/SKIP
stage4/SKIP
stage4/SKIP_IMAGES
stage5/SKIP
stage5/SKIP_IMAGES

The scripts

There are three scripts in this repo:

• getpigenfile.sh copies a file from pi-gen to the current location removing everything before "stage" or "export" and replacing all the path '/'s with '_'s
• setuppigen.sh copy the changed files into the pi-gen directory in preparation for building a new image, also copy any files that will be overwritten into a bak subdirectory of the current directory
• restorepigen.sh copy all the files in the bak directory back to pi-gen and delete any other files that were added

Environment variable

setuppigen.sh and restorepigen.sh can have the path to the pi-gen directory set in a PP evironment variable, they can also have this passed to them on the command line

Intended usage

copy the threee scripts to /usr/local/bin

cd basedirectory
git clone https://github.com/RPi-Distro/pi-gen.git

install the pi-gen dependencies (and if planning to run in docker also install docker and docker-compose)

mkdir myproject
cd myproject

create a file called config with contents similar to below (note you must have ENABLE_SSH=1)

IMG_NAME=example
FIRST_USER_NAME=example
FIRST_USER_PASS=example
TARGET_HOSTNAME=example
ENABLE_SSH=1

copy the files across

getpigenfile.sh ../pi-gen/stageX/0...

create new files with the appropriate names ( e.g. stage2_01-sys-tweaks_files_customfile.txt or stage3_SKIP__IMAGES )

setuppigen.sh
cd ../pi-gen
build.sh # or build-docker.sh
cd -
restorepigen.sh

Create a second project

mkdir myproject2
cd myproject2

create config file

IMG_NAME=example2
FIRST_USER_NAME=user
FIRST_USER_PASS=password
TARGET_HOSTNAME=example
ENABLE_SSH=1

copy the files across

getpigenfile.sh ../pi-gen/stageX/0...

etc.