fling

A wrapper around systemd-nspawn and debootstrap for running isolated tests.
Can be run for local builds, and also ships a web server for usage with gitea.

A sample configuration file for testing bolt

[fling]
commands =
  service postgresql start
  su postgres -s /bin/sh -c 'psql -c "CREATE USER bolt PASSWORD '"'"'bolt'"'"' SUPERUSER" -d postgres'
  su postgres -s /bin/sh -c 'psql -c "CREATE DATABASE bolt_test OWNER bolt" -d postgres'
  export MIX_ENV=test
  export PGSQL_TEST_URL=postgres://bolt:bolt@/bolt_test
  mix local.hex --force
  mix local.rebar --force
  mix deps.get
  mix deps.compile
  mix compile
packages = ca-certificates,elixir,erlang,git,postgresql-11

The packages specified in packages will be cached across invocations.
commands are simply run via shell.

Local usage

Head to your project directory and execute python3 -m fling build as root.

Usage with Gitea

• Create a token in Gitea’s “Application” settings
  (user/settings/applications)
• Start fling with the generated --gitea-token, ensure it is reachable to
  Gitea
• Configure a webhook in your repository to point to
  http://<FLING_ADDR>/hook/gitea
• Configure fling in your repository. See the configuration example above.

Configure root to have SSH keys to clone repositories you want to use it on.

Then, see python3 -m fling server --help for usage. Do not bind fling on a public IP
address.

Once the server is running, add a webhook on your repositories to test, pointing
to the address of the fling server, path /hook/gitea.

Execution

When fling receives a build via its webhook route /hook/gitea, it performs
the following:

• prepare a workspace (checkout the commit to build locally)
• load build configuration (from the default branch or the commit to build, see
  --trust)
• prepares Debian Stable in a chroot if the current one is outdated [1], this is
  called the template machine
• runs build commands in an ephemeral snapshot of the template machine

The commit status is updated on Gitea along the way.

[1] these are determined outdated in two cases: if the directory does not exist
at all, it is always considered outdated and recreated. Otherwise, fling
compares a hashsum of the configuration the image was built with with the
configuration that is desired, and if they mismatch, recreates the image

Dependencies

• Python 3
• debootstrap
• systemd-nspawn
• git
• root access

Setup