Add envsubst so dns-conf credentials can be added from container environment variables

[pentago]

Desired Behavior

Instead of editing /config/dns-conf/cloudflare.ini to hardcode email and API key/token and drag that sensitive credentials through Git (my case), I'd like to have envsubst triggered on container start that takes environment variables like EMAIL and CF_API_TOKEN and replaces those environment variables in files.

Considering user already adds these values to their compose or .env file, it makes little sense to have same creds added in multiple locations if they can be added automatically.

I'm guessing this behavior is applicable to other DNS providers as well.

Current Behavior

The user needs to add the same environment variable values multiple times, once in compose file and second time to cloudflare.ini.

Alternatives Considered

Manually maintaining the same values in multiple places and accidentally checking sensitive creds to git for people who version their setups.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[pentago]

Still interested

[nemchik]

I'll have to look into how much this would require us to change the existing way we're doing things. I'm already considering some other potentially big changes, but not rushing into them as we've got other moving parts as well (Alpine 3.16 and s6v3).

[caboose16]

I'm also interested in envsubst for proxy-confs. Some docker containers use the network_mode host so envsubst would be perfect for passing the host IP to the proxy-confs.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Keviento]

bump