How to override application.properties during prod

Question

I'm using spring boot and application.properties to select a database during development by @Configuration @Profile("dev").

spring.profiles.active=dev
spring.config.location=file:d:/application.properties

During production I'd like to create a file outside of the application context that should be loaded and then active a different configuration profile, with d:/application.properties:

spring.profiles.active=production

Result: when I start the app, the configuration is still dev, so somehow the additional location of the productive properties file is not taken into account. Am I missing anything?

spring boot 1.1.0.BUILD-SNAPSHOT

Note: this question is NOT about tomcat.

Answer 1

The spring configuration precedence is as follows.

1. ServletConfig init Parameter
2. ServletContext init parameter
3. JNDI attributes
4. System.getProperties()

So your configuration will be overridden at the command-line if you wish to do that. But the recommendation is to avoid overriding, though you can use multiple profiles.

Answer 2

You can also use @PropertySources

@PropertySources({
        @PropertySource(value = "classpath:application.properties"),
        @PropertySource(value = "file:/user/home/external.properties", ignoreResourceNotFound = true)
})
public class Application {
    public static void main(String[] args) throws Exception {
        ConfigurableApplicationContext context = SpringApplication.run(Application.class, args);

    }


}

Answer 3

UPDATE: this is a bug in spring see here

the application properties outside of your jar must be in one of the following places, then everything should work.

21.2 Application property files
SpringApplication will load properties from application.properties files in the following    locations and add them to the Spring Environment:

A /config subdir of the current directory.
The current directory
A classpath /config package
The classpath root

so e.g. this should work, when you dont want to specify cmd line args and you dont use spring.config.location in your base app.props:

d:\yourExecutable.jar
d:\application.properties

or

d:\yourExecutable.jar
d:\config\application.properties

see spring external config doc

Update: you may use \@Configuration together with \@PropertySource. according to the doc here you can specify resources anywhere. you should just be careful, when which config is loaded to make sure your production one wins.

Answer 4

I am not sure you can dynamically change profiles.

Why not just have an internal properties file with the spring.config.location property set to your desired outside location, and the properties file at that location (outside the jar) have the spring.profiles.active property set?

Better yet, have an internal properties file, specific to dev profile (has spring.profiles.active=dev) and leave it like that, and when you want to deploy in production, specify a new location for your properties file, which has spring.profiles.active=prod:

java -jar myjar.jar --spring.config.location=D:\wherever\application.properties

Answer 5

I have found the following has worked for me:

java -jar my-awesome-java-prog.jar --spring.config.location=file:/path-to-config-dir/

with file: added.

LATE EDIT

Of course, this command line is never run as it is in production.

Rather I have

• [possibly several layers of] shell scripts in source control with place holders for all parts of the command that could change (name of the jar, path to config...)
• ansible deployment scripts that will deploy the shell scripts and replace the place holders by the actual value.

Answer 6

Update with Spring Boot 2.2.2.Release.

Full example here, https://www.surasint.com/spring-boot-override-property-example/

Assume that, in your jar file, you have the application.properties which have these two line:

server.servlet.context-path=/test
server.port=8081

Then, in production, you want to override the server.port=8888 but you don't want to override the other properties.

First you create another file, ex override.properties and have online this line:

server.port=8888

Then you can start the jar like this

java -jar spring-boot-1.0-SNAPSHOT.jar --spring.config.location=classpath:application.properties,/opt/somewhere/override.properties