Spring Boot Externalization

In this example we are going to externalize MySQL database connection using a yaml file. In order to get the setup for this example, please refer my previous post Spring Boot JPA

First we need to create our yml file in ${USER_HOME}/.spring-boot-jpa/application-development.yaml

spring:
  datasource:
    url: jdbc:mysql://localhost/spring_boot_jpa
    username: username
    password: password
    driverClassName: com.mysql.jdbc.Driver
  jpa:
    generateDdl: true

Next we need to add bootRun closure and specify a system properties in our build.gradle file

buildscript {
  ext {
    springBootVersion = '2.0.6.RELEASE'
  }
  repositories {
    mavenCentral()
  }
  dependencies {
    classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
  }
}

apply plugin: 'java'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'

group = 'com.jos.dem.springboot.jpa'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.8

repositories {
	mavenCentral()
}


dependencies {
  compile('org.springframework.boot:spring-boot-starter-web')
  compile('org.springframework.boot:spring-boot-starter-thymeleaf')
  compile('org.springframework.boot:spring-boot-starter-data-jpa')
  compile("mysql:mysql-connector-java:5.1.34")
  compileOnly('org.projectlombok:lombok')
  testCompile('org.springframework.boot:spring-boot-starter-test')
}

bootRun {
  systemProperties = System.properties
}

That’s it, now we can get our database credentials and connection from an externalized yaml file. In order to read our yaml file as system properties we need to execute this command in Mac or Linux:

gradle bootRun -Dspring.config.location=$HOME/.spring-boot-jpa/application-development.yaml

If you are using Windows platform, use this command:

gradle bootRun "-Dspring.config.location=$HOME/.spring-boot-jpa/application-development.yaml"

To browse the project go here, to download the project:

git clone https://github.com/josdem/spring-boot-jpa.git
git fetch
git checkout feature/externalization

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