[Isomorphic]

Not sure what you mean about "deep inside Isomorphic-generated XML", DataSource.addDynamicDSGenerator() is a Java API, maybe you're seeing a file that's involved in documentation, but that's not relevant here.

You are now in complete lala land having somehow broken DataSource loading in a way we've never seen.

What is this file:/nethome device / server - some kind of NAS system? We suspect that it is, for whatever reason, just not letting our server code access the file. Possibly the server is getting a cached result saying that no such file exists.

[Isomorphic]

Assuming this is a network drive, we'd recommend:

1. shut down your server
2. unmount the drive
3. re-mount the drive
4. verify the file exists on the drive and can be opened
5. start your server again and try the test

[susanpemble]

OK, this is humiliating to post publicly, but I have to own up.

A coworker helping me debug this found that my /shared/ds/ folder was not directly under /war/ where it should be; I had accidentally created it under /WEB-INF/ instead.

Your focus on the path being the issue was absolutely correct.

Thank you for all your time.

[Isomorphic]

Ouch. Thanks for owning up rather than leaving it a mystery!