temporary file folder no longer unique

[bartschuller]

Play Version

2.8.0-M4+

API

Scala

Operating System

Linux primary 4.15.0-96-generic #97-Ubuntu SMP Wed Apr 1 03:25:46 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

JDK

openjdk version "1.8.0_242"
OpenJDK Runtime Environment (build 1.8.0_242-8u242-b08-0ubuntu3~18.04-b08)
OpenJDK 64-Bit Server VM (build 25.242-b08, mixed mode)

Library Dependencies

Expected Behavior

1. We have an existing Play application which uses a file upload form. We're upgrading it from Play 2.6.21 to 2.8.1.
2. Under Play 2.6.21, when a user uploads a file, a temporary directory with a unique name is created, such as /tmp/playtemp189725596617018652
3. We depend on that directory being unique, because the same machine runs multiple independent Play applications, each under their own Unix user.

Actual Behavior

1. The same application upgraded to Play 2.8.1 suddenly creates a directory /tmp/playtemp.
2. It's sister application running on the same machine under a different user tries to create a file within this directory (because it too is using /tmp/playtemp now) , but fails, because it doesn't own it.

Reproducible Test Case

I can trace the regression to commit 940bd88 belonging to #9390 which replaced a call to JFiles.createTempDirectory(TempDirectoryPrefix) with a call to JFiles.createDirectories(Paths.get(s"$dir/$TempDirectoryPrefix")). The latter doesn't use it's argument as a prefix for a unique name.

[mkurz]

Thanks for the report. I will check. Let's target Play 2.8.2 with a fix if necessary.

[mkurz]

@bartschuller Do you want to provide a pull request with a fix?

[bartschuller]

Sorry, I don't have one.

[mkurz]

It's ok, I will take a look.