KepwareSync.Service: Environment Variable Configuration clarification request

[ttosunptc]

Hello,
Example environment variables are shared in readme file under KepwareSync.Service folder. I tested docker deployment with example variables, it works as expected and the service does PrimaryKepServer -> LocalFile.
environment:
- KEPWARE__PRIMARY__USERNAME=Administrator
- KEPWARE__PRIMARY__PASSWORD=StrongAdminPassword2025!
- KEPWARE__PRIMARY__HOST=https://kepware:57513
- STORAGE__DIRECTORY=/app/config

I'm requesting information how to define environment variables related to secondary. Changing the word "PRIMARY" in the example variables (such as KEPWARE__SECONDARY__USERNAME) seems to take no effect on container.

There is a workaround that includes mapping the appsettings.json to the host system, but I'd like to do the synchronization by using the environmental variables without touching the json file. The readme file has a reference to "AddEnvironmentVariables" function, if this is the way to add more variables, please let me know to modify it.

I'm also wondering how to use other service commands as env vars as well, such as "--kep-sync-mode" and "--kep-sync-direction".

Best,
Tahsin Tosun

[rlabbeptc]

Hi @ttosunptc ,

The service uses the configuration builder in .NET and the binding of the parameters will use the result of the configuration builder, which has env variables as the highest priority. Essentially the environmental variable syntax would look like this:

How to name environment variables
• The environment variable provider maps configuration key separators to __ (double underscore). Example mappings:
• Kepware:Primary:Host -> Kepware__Primary__Host
• Kepware:Primary:UserName -> Kepware__Primary__UserName
• Kepware:Primary:PasswordFile -> Kepware__Primary__PasswordFile
• Kepware:DisableCertificateValidation -> Kepware__DisableCertificateValidation

For arrays / lists (the Secondary list) use indexed keys:
• Kepware__Secondary__0__UserName, Kepware__Secondary__0__Password, Kepware__Secondary__0__Host
• Kepware__Secondary__1__UserName, etc.

These essentially adopt the same key-value structure of the appsettings.json file provides.

I'll update the readme doc to help provide more clarity. I suspect for container deployments, users would likely provide the appsettings.json most of the configuration with a secrets methodology for passwords. This could be refined in the future before any initial release.