gitea/contrib/environment-to-ini

Environment To Ini
==================

Multiple docker users have requested that the Gitea docker is changed
to permit arbitrary configuration via environment variables.

Gitea needs to use an ini file for configuration because the running
environment that starts the docker may not be the same as that used
by the hooks. An ini file also gives a good default and means that
users do not have to completely provide a full environment.

With those caveats above, this command provides a generic way of
converting suitably structured environment variables into any ini
value.

To use the command is very simple just run it and the default gitea
app.ini will be rewritten to take account of the variables provided,
however there are various options to give slightly different
behavior and these can be interrogated with the `-h` option.

The environment variables should be of the form:

	GITEA__SECTION_NAME__KEY_NAME

Environment variables are usually restricted to a reduced character
set "0-9A-Z_" - in order to allow the setting of sections with
characters outside of that set, they should be escaped as following:
"_0X2E_" for ".". The entire section and key names can be escaped as
a UTF8 byte string if necessary. E.g. to configure:

	"""
	...
	[log.console]
	COLORIZE=false
	STDERR=true
	...
	"""

You would set the environment variables: "GITEA__LOG_0x2E_CONSOLE__COLORIZE=false"
and "GITEA__LOG_0x2E_CONSOLE__STDERR=false". Other examples can be found
on the configuration cheat sheet.

To plug this command in to the docker, you simply compile the provided go file using:

	go build environment-to-ini.go

And copy the resulting `environment-to-ini` command to /app/gitea in the docker.

Apply the below patch to /etc/s6/gitea.setup to wire this in.

If you find this useful please comment on #7287


diff --git a/docker/root/etc/s6/gitea/setup b/docker/root/etc/s6/gitea/setup
index f87ce9115..565bfcba9 100755
--- a/docker/root/etc/s6/gitea/setup
+++ b/docker/root/etc/s6/gitea/setup
@@ -44,6 +44,8 @@ if [ ! -f ${GITEA_CUSTOM}/conf/app.ini ]; then
     SECRET_KEY=${SECRET_KEY:-""} \
     envsubst < /etc/templates/app.ini > ${GITEA_CUSTOM}/conf/app.ini

+    /app/gitea/environment-to-ini -c ${GITEA_CUSTOM}/conf/app.ini
+
     chown ${USER}:git ${GITEA_CUSTOM}/conf/app.ini
 fi