SpringBoot Path expansion for ~ in logging.file.name or logging.file.path

At the moment the configuration properties logging.file.name and logging.file.path will not expand the ~ character to the home directory, whether on Windows or Unix systems, and instead will create a directory named ~.

It would be nice if Spring Boot could automatically expand the ~ character, which would allow for multi-platform configuration that relates to the user's home directory.

For instance when using H2, the spring.datasource.url will correctly expand the ~ character.

I lodge this as a feature request since the documentation does not mention that path expansion is supported.

Comment From: wilkinsona

Configuration properties already support placeholder replacement in their values and any placeholder that matches a property in the environment will be replaced. The user.home system property is part of the environment so you can use ${user.home} to place a file within your home directory. For example logging.file.name=${user.home}/app.log will result in the log file being written to ~/app.log.

Comment From: gotson

It doesn't seem to be working with properties in yaml though.

EDIT: My bad, it was conflicting with my gradle configuration:

withType<ProcessResources> {
    filesMatching("application*.yml") {
      expand(project.properties)
    }
  }

Comment From: wilkinsona

It should work with both .properties and .yaml files.

logging:
  file:
    name: ${user.home}/yaml.log

I've just double-checked and the YAML above results in the logs being written to ~/yaml.log.

Comment From: gotson

@wilkinsona this is working indeed, however the syntax conflicts with the Groovy template for variable replacement of Gradle. This is complicating things, for example the above snippet is used in Gradle projects to replace the application version for Spring Boot to pickup:

application.version: ${version}

EDIT: after some quick googling, the Spring placeholder can be escaped, see here

All good then, thanks a lot everyone!