INITIAL_API_KEY_FILE not working as documented

[Maypul]

Shlink version

4.2.1

PHP version

4.2.1

How do you serve Shlink

Docker image

Database engine

PostgreSQL

Database version

16.3

Current behavior

When setting up INITIAL_API_KEY_FILE the initial API key is not being created. Using INITIAL_API_KEY works as intended.

As documented in https://shlink.io/documentation/environment-variables/#secret-env-vars
"Starting with Shlink 4.0.0, you can pass any environment variable with the _FILE suffix."

As a side request, if it would be implemented, could web client also use SHLINK_SERVER_API_KEY from the docker secret file?

Expected behavior

INITIAL_API_KEY_FILE loads value from the client and creates initial API key.

Minimum steps to reproduce

Create a docker container with the

shlink:
(...)
secrets:
- source: shlink_api_key
target: /run/secrets/shlink_api_key
environment:
(...)
INITIAL_API_KEY_FILE: /run/secrets/shlink_api_key

[acelaya]

Did you set the file env var on the very first Shlink boot up?

The initial API key is special, and only set once if no other API keys exist yet.

If you started Shlink with the non-file env var and then switched to the file one, Shlink will ignore it.

[acelaya]

Actually, scratch that. I see the problem.

This env var is different than the rest, in which it's not read by Shlink at runtime, but in the docker container entry point. See

shlink/docker/docker-entrypoint.sh

Line 17 in a8e4b2f

if [ -n "${INITIAL_API_KEY}" ]; then

That is missing the logic to fall back to the _FILE suffixed env var for obvious reasons because that's implemented in PHP.

I'll need to investigate how to support it there.

[acelaya]

In order to fix this I'm introducing a helper command to Shlink that will return the value for any supported env var, but making sure the fallback logic to _FILE is applied.

Then I will use that command in non-php scripts (like the docker entry point) to get the values of env vars, rather than reading env vars directly.

That should solve this problem for the INITIAL_API_KEY env var and other two env vars that are read in the entry point and are affected by this, even if nobody noticed yet.

[acelaya]

I have just released Shlink 4.2.2. You should be able to pass INITIAL_API_KEY_FILE in that version.

[Maypul]

Seems to be working according the the log, thanks!

Initializing database if needed... Success!
Updating database... Success!
Generating proxies... Success!
Clearing entities cache... Success!
Downloading GeoLite2 db file... Success!
Creating first API key... Success!