使用带有 Spring 引导的 dotenv 文件

Question

I'd like to use dotenv files to configure my Spring Boot application.

What is the best way to do this?

In Ruby or Node world, I just creating .env file and it loads all stuff from there to application environment.

I don't like to create separate profiles for my app etc. I just want to load any environment variables I specified in file into my app.

Answer 1

I have built a proper integration between Spring and dotenv .

Follow this thread to understand the motivation. And then review the library:

Check out the spring-dotenv library here:
https://github.com/paulschwarz/spring-dotenv

The library includes a sample application to show you how to use it, and there you see that the integration with Spring is very natural:

https://github.com/paulschwarz/spring-dotenv/tree/master/application/src/main/resources

I stuck to two principles in designing this library:

1. https://12factor.net/config
2. Allow your code to be completely unaware of dotenv so that you continue to reference your application.yml/application.properties files using the normal Spring techniques. No funny business.

Answer 2

There's actually a java port of 'dotenv' tool.

https://github.com/cdimascio/dotenv-java

Answer 3

In spring boot just do that in application.yml

---
spring:
    config:
      import: optional:file:.env[.properties]

username: ${USERNAME}

or if you use application.properties

spring.config.import=optional:file:.env[.properties]
username=${USERNAME}

Then @value and all other stuff will work