Spring Profiles and @Profile

1. Overview

Profiles are a core feature of the framework — allowing us to map our beans to different profiles — for example, dev, test, and prod.

How to set Profiles for Spring
How to active Profiles in Spring
How to get active Profiles in Spring

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Profiles in Spring Boot

Spring Boot supports all the profile configuration outlined so far, with a few additional features.

1. Activating or Setting a Profile

# 方式1： 配置文件里配置
spring.profiles.active=dev

# 方式2：使用SpringApplication
SpringApplication.setAdditionalProfiles("dev");

# 方式3:
# Set profiles using Maven in Spring Boot
<plugins>
    <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        <configuration>
            <profiles>
                <profile>dev</profile>
            </profiles>
        </configuration>
    </plugin>
    ...
</plugins>
# and execute the Spring Boot-specific Maven goal:
mvn spring-boot:run

2. Profile-specific Properties Files

The most important profiles-related feature that Spring Boot brings is profile-specific properties files. These have to be named in the format application-{profile}.properties.

For example, we can configure different data sources for dev and production profiles by using two files named application-dev.properties and application-production.properties:

# In the application-production.properties file, we can set up a MySql data source:
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/db
spring.datasource.username=root
spring.datasource.password=root

# In the application-dev.properties file, to use an in-memory H2 database:
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.url=jdbc:h2:mem:db;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=sa

In this way, we can easily provide different configurations for different environments.

3. Multi-Document Files

Club all the properties in the same file and use a separator to indicate the profile
Starting version 2.4, We can specify the dev and production properties in the same application.properties:

my.prop=used-always-in-all-profiles
#---
spring.config.activate.on-profile=dev
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/db
spring.datasource.username=root
spring.datasource.password=root
#---
spring.config.activate.on-profile=production
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.url=jdbc:h2:mem:db;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=sa

This file is read by Spring Boot in top to bottom order.

参考：Spring Profiles