Play dynamically fill in application.conf from external properties file

Question

My project setup looks as follows:

I would like to dynamically fill in application.conf values.

These values should be read from the correct properties file (${env}.props.properties). The correct properties file depends on the property env which is given with a run or build command (Denv=xxx).

application.conf
key=${my.property.value.read.from.props.properties.file}
key2=...

Thanks in advance!

Answer 1

You can tell Typesafe Config to load a different config file altogether by specifying flag -Dconfig.resource=your.file.properties as you run your application. If the config file is not a bundled resource you can use -Dconfig.file=/path/to/your.file.properties instead. (You can also specify an URL with -Dconfig.url ; see https://github.com/typesafehub/config#user-content-standard-behavior for more info)

Doing this will skip loading application.conf altogether so remember to set Play!-specific properties in your own properties-file.

Answer 2

You can try Typesafe ConfigFactory.invalidateCaches to invalid config entries. As api doc says; first make the changes then call above api, followed by load() (one solution would be to have a scheduler that calls it every x interval). Disclaimer - I haven't tried it myself https://lightbend.github.io/config/latest/api/com/typesafe/config/ConfigFactory.html#invalidateCaches--