Consider this Dockerfile:

FROM openjdk:17
COPY . .
EXPOSE 8999
RUN ./gradlew build
CMD java -jar -Dspring.profiles.active=local build/libs/example.jar

I can build this without problems with:

docker build -t example-service .

and run it with

docker run -p 8999 -d example-service

when I have a gradle.properties file in the root folder (where I do COPY . .) with the following content:

artifactoryUsername=user1
artifactoryPassword=password1

This works because I have the following snippet in my build.gradle:

...
repositories {
    mavenLocal()
    mavenCentral()
    maven { url 'https://repo.spring.io/snapshot' }
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repository.aspose.com/repo/' }
    maven {
        url 'https://my-url/artifactory/example-maven/'
        credentials {
            username artifactoryUsername
            password artifactoryPassword
        }
    }
}
...

However, I don’t want to copy the gradle.properties with secret information into the container.
(How) can I use docker build‘s --secret-option to do that? Or would you recommend something else?