Before this commit, the latest version of Raspbian was chosen.
It is not very helpful though as if something goes wrong, we don't on which part it is.
Also, fix python dependencies for the image
- ngrok download URL has changed
- default kernel for raspbian image has changed and needs to match
- remove pre-existing git checkout to avoid conflicting
- wait a few seconds after setting up loop dev with kpartx to access image
contents - sometimes required to let the device appear in /dev
The main reason for doing this is supporting the new Raspberry Pi 3. No
functional changes where made.
For Raspbian Wheezy we used to download the full image and strip it as
best we could to obtain a reasonable image size for people to
download. Since Raspbian Jessie the Raspberry Pi Foundation has started
releasing an official minimal image (Raspbian Jessie Lite) which we will
use from now on to build our image. One downside of this is that the
minimal image is a 1.3 GiB image which is too small for our
purposes so it has to be resized.
Because Raspbian Jessie migrated to systemd we cannot rely on
/etc/init.d/rcS to set up the ramdisks anymore. Jessie provides a
compatibility layer so old SysVinit scripts still work but rcS does not
block like it does in a SysVinit system, it is run in parallel with
other startup services. In our case this is a bad thing as setting up
the ramdisks has to be done before any other services are started. To
accomplish this the rcS hack has been migrated to a systemd service
running before basic.target and with DefaultDependencies=no. This has a
similar effect as the rcS hack because normal systemd services (with
DefaultDependencies=yes) all require basic.target by default.
Instead of continuing to build upon the old images, these scripts
implement a reproducable way to generate new posbox images. The
generated images will be based on the latest stable Raspbian
release. The image will be created with the help of qemu-system-arm,
which will boot up the image and execute a script that will set up the
posbox image.
This way everything necessary to set up a posbox is readable in the
scripts and accompanying files, instead of being hidden in an image.
Lucas Perais (lpe)
Olivier Dony
Joren Van Onder