[SOLVED] How to use kubernetes container environment variables under prometheus black box?

How to use kubernetes container environment variables under prometheus black box?

I have created the username and password in the vault and mounted those secrets as secret name my_sec in k8 pod.

Then I injected that secret my_sec inside my BlackBox container. When I ran printenv, I can also see env variables - username and password along with their values.

However, when I use/reference username and password environment variables under my BlackBox configuration http_2xx module (as mentioned below), environment variables $(username) and $(password) are not replaced by their respective values.

Can someone please assist me with the proper syntax or configuration, I should be able to make environment variables working under BlackBox http_2xx module.

basic_auth:
Username: $(username)
Password: $(password)

Solution

Prometheus does not support environment variables for other fields than proxy settings in http_config. If you add the secrets to your blackbox exporter, you can use username_file and password_file.

basic auth:
  username_file: <path_to_username_secret>
  password_file: <path_to_password_secret>

Example:

basic auth:
  username_file: /run/secrets/my_username
  password_file: /run/secrets/my_password

The documentation is available here, it should answer any other questions regarding options you may have.