Spring Boot PostProcessor for Docker Secrets

Docker secrets are mounted to the container on a file basis. This is an approach not support by Spring out of the box.

The class DockerSecretEnvPostProcessor reads these secret files and creates properties usable like any other spring property.

# `docker_secret_` is the prefix and `email_username` the name of the secret file
app.email.username=${docker_secret_email_username}

Setup

To enable this post processor you have to create src/main/resources/META-INF/spring.factories containing

org.springframework.boot.env.EnvironmentPostProcessor=com.byteowls.docker.boot.DockerSecretEnvPostProcessor

Configure

After that you can configure the post processor from your application-<env>.properties or any other Spring supported mechanism.

#key=default_value

# enable/disable the post processor during runtime
docker.boot.secret.enabled=true
# docker secret mount path
docker.boot.secret.path=/run/secrets
# prefix for secret name 
docker.boot.secret.prefix=docker_secret_
# remove leading and trailing whitespace chars
docker.boot.secret.trim=true
# print errors to System.out
docker.boot.secret.print.errors=true
# Attention: print all found secrets (masked) to System.out. Use with care.
docker.boot.secret.print.secrets=false
# Attention: unmasks all printed secrets. Use with care.
docker.boot.secret.print.secrets.unmasked=false

Note: We print to System.out because the log system is not ready, when the post processor is executed.

Dependency

Maven

<dependency>
    <groupId>com.byteowls</groupId>
    <artifactId>docker-secret-spring-post-processor</artifactId>
    <version>replace.with.version</version>
</dependency>

Gradle

dependencies {
  implementation "com.byteowls:docker-secret-spring-post-processor:REPLACE.WITH.VERSION"
}

Contribute

See Contribution Guidelines.

Gradle

./gradlew wrapper --gradle-version 6.8.3

Changelog

See CHANGELOG.

License

MIT. Please see LICENSE.

BYTEOWLS Software & Consulting

This plugin is powered by BYTEOWLS Software & Consulting.

If you need extended support for this project like critical changes or releases ahead of schedule. Feel free to contact us for a consulting offer.