docker中的SpringBoot环境为null

Question

I have a springboot java application with gradle and some environment variables in application.yml :

spring:
  profiles: development
server:
  port: 3100
database:
  connectionString: mongodb://localhost:27017

---

spring:
  profiles: production
server:
  port: 80
database:
  connectionString: prodCS

My dockerfile :

FROM openjdk:8-jdk-alpine
VOLUME /tmp
ARG JAR_FILE
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom", "-Dspring.profiles.active=development","-jar","/app.jar"]

I am trying to run the docker locally but my environment returns null properties

@Configuration
public class MongoUtilities {
  @Resource
  public Environment env;
  private static String mongoUri;

  @Bean
  public static PropertySourcesPlaceholderConfigurer propertyPlaceHolderConfigurer() {
    return new PropertySourcesPlaceholderConfigurer();
  }

  @Bean
  public boolean ReadConnectionString() {
    mongoUri = env.getProperty("database.connectionString");
    System.out.println("Loaded connection Uri : " + mongoUri);
    return true;
  }
}

I've had trouble before with the environment variable being null but managed to fix it. It now runs perfectly in intellij with flag --spring.profiles.active=development

I am building using gradlew build docker and starting docker using docker run springio/my-app

It's all pretty standard, I'm just a beginner to this area.

Any ideas?

Answer 1

Alright, I've manager to fix it by adding my application.yml to the docker in build.gradle:

docker {
  dependsOn build
  name "${project.group}/${bootJar.baseName}"
  files bootJar.archivePath, 'application.yml'
  buildArgs(['JAR_FILE': "${bootJar.archiveName}"])
}

Then I had to copy application.yml to the image using the dockerfile

COPY application.yml application.yml

Then I set spring's configuration to my application.yml

ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom", "-Dspring.config.location=application.yml", "-jar","/app.jar"]

Answer 2

There are a couple of ways of doing it namely

• Passing Spring Profile in Dockerfile

   ENTRYPOINT ["java", "-Djava.security.egd=file:/dev/./urandom","-Dspring.profiles.active=dev","-jar","/rest-api.jar"] 

• Passing Spring Profile in Docker run command

    docker run -d -p 8080:8080 -e "SPRING_PROFILES_ACTIVE=dev" --name rest-api dockerImage:latest 

• Passing Spring Profile in DockerCompose

    rest-api: image: rest-api:0.0.1 ports: - "8080:8080" environment: - "SPRING_PROFILES_ACTIVE=dev" 

I have written in detail over here , how you can achieve the above 3 approaches.