如何从 Linux 命令行或 docker 容器中检查 spring 启动 java 应用程序消耗了哪些值

Question

How to check what values are consumed by a spring boot java application from the Linux command line or in the docker container?

I have a spring boot java application that has the below parameters for email

spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username=admin@qtech.com
spring.mail.password=${GPASSWORD}
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.ssl.trust=smtp.gmail.com

I'm passing GPASSWORD as an environment variable to the docker/k8s container.

How can I check what value/values are being consumed by the java application, especially spring.mail.password field.

I tried the below commands

printenv 

env 

But they list all environment variables being passed to all containers like the below environment variable.

GPASSWORD=bond007

So Is there a way to check what values are being consumed by the spring boot java application inside a pod or container?

Answer 1

You can use Slf4j annotation and log like below:

@Value("${spring.mail.host}")
private String mailHost;

log.info("spring.mail.host: "+mailHost);