Fallback for environment variables with docker-compose
问题 Given the following configuration: mysql: environment: MY_MYSQL_PORT: image: mysql ports: - "${MY_MYSQL_PORT}:3306" There's a way to provide a fallback value for MY_MYSQL_PORT without relying on wrapper scripts? I already tested like bash ${MY_MYSQL_PORT-3306} but it doesn't work. 回答1: They implemented that feature with compose 1.9 release: Added support for shell-style inline defaults in variable interpolation. The supported forms are ${FOO-default} (fall back if FOO is unset) and ${FOO: