我有一个Sping Boot Backend，它在我的IntelliJ本地机器上运行得很好。
但是当我尝试在Docker容器上运行它时，我得到了这个错误

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'emailSenderService' defined in URL [jar:file:/app/Backend-0.0.1-SNAPSHOT.jar!/com/hdmstuttgart/mi/backend/service/EmailSenderService.class]: Unexpected exception during bean creation; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'mjmlSecrets.appId' in value "${mjmlSecrets.appId}"
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:555)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
openbarber-backend-1   |        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
openbarber-backend-1   |        at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
openbarber-backend-1   |        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391)
openbarber-backend-1   |        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
openbarber-backend-1   |        at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887)
openbarber-backend-1   |        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
openbarber-backend-1   |        ... 32 common frames omitted
openbarber-backend-1   | Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'mjmlSecrets.appId' in value "${mjmlSecrets.appId}"
openbarber-backend-1   |        at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:180)
openbarber-backend-1   |        at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:126)
openbarber-backend-1   |        at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:239)
openbarber-backend-1   |        at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:210)
openbarber-backend-1   |        at org.springframework.context.support.PropertySourcesPlaceholderConfigurer.lambda$processProperties$0(PropertySourcesPlaceholderConfigurer.java:191)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:936)
openbarber-backend-1   |        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1332)
openbarber-backend-1   |        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
openbarber-backend-1   |        at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887)
openbarber-backend-1   |        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
openbarber-backend-1   |        at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:229)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)
openbarber-backend-1   |        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
openbarber-backend-1   |        ... 41 common frames omitted
openbarber-backend-1 exited with code 1

字符串
它似乎无法解析本例中的占位符的某些凭据。
在application.yml中，凭据的配置如下

mailCredentials:
  username: ${MAIL_USERNAME}
  password: ${MAIL_PASSWORD}
mjmlSecrets:
  appId: ${MJML_APP_ID}
  appKey: ${MJML_APP_KEY}

型
凭证在.env文件中

MAIL_USERNAME=yourMailUsername
MAIL_PASSWORD=yourMailPassword
MJML_APP_ID=yourMjmlAppId
MJML_APP_KEY=yourMjmlAppKey

型
在docker-compose文件中，我也这样设置了环境变量

version: '3.8'
services:
  frontend:
    hostname: localhost
    build: ./Frontend
    ports:
      - "80:80"
  backend:
    build: ./Backend
    ports:
      - "8080:8080"
    depends_on:
      - db
    links:
      - db
    environment:
      - SPRING_DATASOURCE_URL=jdbc:postgresql://db:5432/openbarber
      - SPRING_DATASOURCE_USERNAME=postgres
      - SPRING_DATASOURCE_PASSWORD=admin
      - MJML_APP_ID=...
      - MJML_APP_KEY=...
      - MAIL_USERNAME=...
      - MAIL_PASSWORD=...
    env_file:
      - ./Backend/src/main/resources/.env

型
配置正确吗？我也试过mvn clean install