Apparently using sleep with very large numbers is not a good idea
when your image can be compiled down to 32-bit platforms.
This fix uses `sleep infinity` and -- failing that -- tries to
sleep for about 68 years (which is exactly 2^15 seconds).
Summary
^^^^^^^
This commit refactors the code base to be more manageble and
prepares the groundwork for tests.
Refactoring
^^^^^^^^^^^
Files are now moved to subdirectories, all for the sole purpose of
easier management. Tests live in their own folders, as well as configs
and other files.
Test framework
^^^^^^^^^^^^^^
Two new important scripts/directories are available:
- `unit-tests.sh` / `/unit-test` which executes unit tests across shell
scripts, and
- `integration-test.sh` / `integration-tests`, which spins up the
container and tries to send the email.
Both tests use the [BATS](https://github.com/sstephenson/bats) framework
for testing. To create a new test, simply drop a `.bats` file into a
corresponding directory.
Functions have been extracted into `common-run.sh`, to be able to test
them independently.
DKIM_SELECTOR
^^^^^^^^^^^^^
It is now possible to specify a DKIM selector to use (instead of
the default "mail"). See `README.md` for more details.
JSON logging
^^^^^^^^^^^^
WIP: rsyslog will now output JSON logs. This is especially important
if you plan on deploying the image into Kubernetes, as [Prometheus](https://prometheus.io/)
can handle logs in JSON much easier.
TODO: Make this an optional feature, to not confuse existing users.
