ADD datasouce to enviroment variable

[AntonBushmelev]

Is your feature request related to a problem? Please describe.
I'm always frustrated when the datasource configuration is hardcoded into the exporter, as it limits flexibility and makes it difficult to adapt to different environments without modifying the configuration file or source code.

Describe the solution you'd like
I need the ability to specify the datasource (e.g., connection string for Microsoft SQL Server) via environment variables. This would allow for more dynamic and flexible deployments, especially in containerized environments like Docker or Kubernetes.

Describe alternatives you've considered

Using configuration files, but this adds complexity in managing separate files for different environments.
Passing the datasource as a command-line argument, but this can expose sensitive information in logs.
Additional context
Adding support for environment variables would improve usability in modern CI/CD pipelines and containerized setups. Examples of expected environment variables:

MSSQL_EXPORTER_DATASOURCE: The full connection string to the SQL Server.
MSSQL_EXPORTER_USERNAME and MSSQL_EXPORTER_PASSWORD: Individual credentials for constructing the datasource dynamically.
This feature is essential for secure and scalable deployments in diverse environments.

[burningalchemist]

Hi @AntonBushmelev, the environment variables are already implemented, please have a look here - #430

You can also define your own environment variables and interpolate them as needed. For that make sure to pass them as ${YOUR_ENV} to the DSN string.

Try it out and let me know if you need any assistance.

I'll move this issue to discussions for the time being.