Careeroza

Real World Example

ShopEase Configuration per Environment

A typical company project keeps one config per environment (profiles are explained in the Spring Boot material):

Profiles for dev and prod

# application.yml (shared)
spring:
  jpa:
    open-in-view: false
    properties:
      hibernate:
        jdbc.time_zone: UTC
---
# application-dev.yml: developer laptop
spring:
  datasource:
    url: jdbc:mysql://localhost:3306/shopease_dev
    username: root
    password: root
  jpa:
    hibernate.ddl-auto: update
logging.level.org.hibernate.SQL: DEBUG
---
# application-prod.yml: production server
spring:
  datasource:
    url: jdbc:mysql://${DB_HOST}:3306/shopease
    username: ${DB_USER}
    password: ${DB_PASSWORD}
    hikari:
      maximum-pool-size: 20
  jpa:
    hibernate.ddl-auto: validate      # never change prod schema automatically

Example output

$ java -jar shopease.jar --spring.profiles.active=prod
INFO  ShopEaseApplication : The following 1 profile is active: "prod"
INFO  HikariDataSource    : HikariPool-1 - Start completed.
INFO  LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'

Why These Choices

  • Passwords from environment variables: never commit production credentials to Git.
  • ddl-auto: validate in prod: the app refuses to start if an entity and the table disagree, instead of corrupting data.
  • open-in-view: false: avoids hidden database queries while rendering the response (explained in the advance level).
  • jdbc.time_zone: UTC: all timestamps stored in UTC; convert to IST only for display.
  • SQL logging only in dev.

Exercise

Exercise: Write an application.yml for a test profile that uses an in-memory H2 database, recreates the schema on each run and logs SQL with parameter values.

Show answer
spring:
  datasource:
    url: jdbc:h2:mem:shopease_test
    username: sa
    password:
  jpa:
    hibernate:
      ddl-auto: create-drop
    properties:
      hibernate:
        format_sql: true
logging:
  level:
    org.hibernate.SQL: DEBUG
    org.hibernate.orm.jdbc.bind: TRACE