In order to get the keystore location as an input value, I would perform the following,
* I would create a file which has all the keystore location and add it in a shared folder which can be accessed by all environment.
* Then, In Virtual DataPort create a Delimited Data source and point to that file and create the base view.
* Then perform a join between the delimited base view and the custom Stored procedure. Execute the view to get the expected results.
In Denodo Platform, a VQL includes a properties file that contains all the information about the environment dependent properties. When you export VQL, a properties file will be generated. You can edit it based on the target environment and point to the keystore file.
For more information, you can refer the following documents [Exporting Environment-Dependent and Independent Elements to Different Files](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/exporting_and_importing_the_server_metadata/exporting_and_importing_elements_across_different_environments/exporting_and_importing_elements_across_different_environments) and the [Delimited File](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/creating_data_sources_and_base_views/delimited_file_sources/delimited_file_sources) of the Virtual DataPort Administration Guide.
Besides that, if you are a valid support user, then I would suggest you to raise this as a Service Request in the Support Site and the Denodo support Team would be able to help you with this requirement.
Hope this helps!