Delete Tomcat's temporary directories when the context is closed

Using Spring Boot 1.5.1.

The directory /tmp/tomcat-* are not deleted when stopping a Spring Boot application. The directory is created using (in org.springframework.boot.context.embedded.AbstractEmbeddedServletContainerFactory) :

File tempDir = File.createTempFile(prefix + ".", "." + getPort());
			tempDir.delete();
			tempDir.mkdir();
			tempDir.deleteOnExit();
			return tempDir;

I think that deleteOnExit() method doesn’t work if the directory is not empty. I made a little standard Java test:

public static void main(String[] args) throws IOException, InterruptedException {
		File tempDir = File.createTempFile("prefix", "suffix");
		tempDir.delete();
		tempDir.mkdir();
		tempDir.deleteOnExit();
		
		try (FileOutputStream os = new FileOutputStream(new File(tempDir, "noempty.txt"))) {
			os.write("This a not an empty file".getBytes());
		}
		Thread.sleep(Long.MAX_VALUE);
	}

Then I send a linux signal kill -15 <pid> but the folder ‘prefix*’ is still here.

[shollander]

@wilkinsona I have found that the shutdown hook created by

https://github.com/spring-projects/spring-boot/blob/b164b16c21734a8581b39553594f102a75bb9738/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/server/AbstractConfigurableWebServerFactory.java#L176

is never effective since there are other directories that get created underneath that top level directory. I am always left with the following directory tree

/tmp
   \- tomcat.123456789.8080
                          \- work
                                \- Tomcat
                                        \- localhost
                                                   \- ROOT

The directory tree is empty, but will not be cleaned up since the top level tomcat.* directory contains an empty directory. Perhaps a better way to do this would be to create a shutdown hook that would remove the entire directory tree if it does not contain any files.

That being said, I am not sure I understand what you mean by

Thanks for the suggestion, but if we always cleared out the whole directory on exit, we’d then get complaints from users who wanted it to remain. For example, users of JSPs may want the directory to remain so that unchanged JSPs don’t need to be recompiled.

The directory created using File.createTempFile() https://github.com/spring-projects/spring-boot/blob/b164b16c21734a8581b39553594f102a75bb9738/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/server/AbstractConfigurableWebServerFactory.java#L173 is guaranteed to be unique and will never be reused after the process exits so it should be safe to force deletion even if the directory does contain files.

[snicoll]

@bbossola server.tomcat.basedir controls the location. We only create a temp dir if that property isn’t specified.