spring-boot-config

Spring Boot Configuration Contract

Configuration files

• Prefer YAML configuration (application.yml) over .properties files.
• Keep settings shared by every environment in application.yml.
• Quote string configuration values consistently in YAML.
• Never commit secrets, passwords, tokens, or private keys as plain values; load them from environment variables or an external secret source.

Virtual threads

• Enablement of spring.threads.virtual.enabled is owned by the virtual-threads contract. Do not restate or override that flag here.

Profiles

• Every application ships both profile files:

  • application-development.yml
  • application-production.yml

• Use the full profile names development and production only. Never use short forms such as dev, prod, local, or prod-like.

• Put environment-specific overrides only in the matching profile file (for example server port, stack-trace exposure, or Swagger enablement). Actuator health-detail overrides are owned by the Actuator contract.

• An optional application-test.yml is allowed when automated tests need a dedicated profile; do not replace development or production with test.

• Declare the active profile in application.yml using list form, with production as the committed default and development available as a commented alternative:

  spring:
    profiles:
      active:
        # - "development"
        - "production"
  

• Prefer overriding the active profile at runtime with SPRING_PROFILES_ACTIVE, a command-line argument, or container/orchestration configuration when switching environments, rather than editing committed defaults casually.

• Typical HTTP overrides when the application exposes a web port:

  • development: port 8080, server.error.include-stacktrace: "always"
  • production: port 9443, server.error.include-stacktrace: "never"

• When OpenAPI/Swagger is present, enable it in development and disable it in production.