For people using slow, expensive, and/or flaky internet, liberal use of
caching can make a huge difference. The restricted environment of the
gpjenkins box has been a good test environment for this (Tor-only,
whitelist of allowed IPs to visit, home internet connection).
For running in QEMU/KVM guests like on jenkins.debian.net, this sets up the
whole process automatically. This only really covers the case where this
is running in a KVM guest, and the original case of running VirtualBox on
bare metal. It could be extended to cover more cases if someone wanted to.
4 gigs is still a common amount of RAM these days for laptops, if the VM
takes almost all of that, it makes the machine drag to almost a halt. Most
apps build fine in 1gig of RAM, indeed that's the default for most CI
instances, like travis-ci and gitlab-ci.
On slow machines or VMs like the Debian jenkins box, the VM boot timeout
needs to be a lot longer, otherwise vagrant times out before setting up
the VM.
This also provides a config option to override that default. ~/.cache is
a standard location on GNU/Linux machines for cached content. It is also
good to have the cache outside of the git repo in case `git clean -fdx` is
run, which would delete all files in the directory that are not part of the
git repo, including buildserver/cache/
This makes it so that ./makebuildserver will run without any config file,
using the defaults that are embedded in the script itself. This is like
how `fdroid` works.
This host automatically detects which is the closest mirror, then uses that
one. It does so dynamically, so it'll work on machines that move too. Now
that we are pushing more people to run F-Droid build servers, the defaults
should take those use cases into account.
This keeps the numbers of names down to a minimum, and since the config
is placed right next to the script, this keeps tab completion working
nicely when the config file is in place.
The old file name is still supported.
