Spring Boot Devtools: Detect automatic restart and apply configuration - spring

Question

I want to set properties that apply only during the automatic restarts provided by Spring Boot developer tools. Is there a way to achieve this?
In other words, is there a way for some part of my code (maybe a configuration bean or a listener) to detect that a restart is under way?
In my specific use case I want to run some SQL scripts during the regular Spring Boot application startup, but not after Devtools has triggered a restart (so that my database state doesn't change during restarts).

Answer 1

Here's an idea:
It's confusing to explain, but you'll see with the code below. When Spring-Boot starts with devtools in its dependencies, it first starts and then immediately restarts a first time trough devtools. You could dynamically add command line argument to track the restarts and change the Spring profile being used when devtools is restarting:
#SpringBootApplication
public class App {
public static void main(String[] args)
throws ParseException, IOException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
String profile = "";
//(1) Very first time - Spring Boot doesn't really load, it only kick start devtool then restarts.
if (args.length == 0) {
args = new String[] { "spring-boot-loaded" };
profile = "no-devtools-yet";
}
//(2) The first time the application loads with devtools
else if (args.length == 1 && args[0].equals("spring-boot-loaded")) {
args = new String[] { "spring-boot-loaded", "devtools-loaded" };
profile = "devtools";
Field argsField = Restarter.class.getDeclaredField("args");
argsField.setAccessible(true);
argsField.set(Restarter.getInstance(), args);
}
//(3) This is the first restart - You don't want to re-initialized the database here
else {
profile = "devtools-reloaded";
}
new SpringApplicationBuilder() //
.sources(App.class)//
.profiles(profile) //
.run(args);
}
}
The sketchy part is that the Restarter keeps the original arguments (which would be "no-devtools-yet" in this example). So when devtools first starts, you need to replace the Restarter's internal args