NetworkTables 4 Subscription not sending all values

[tsar-boomba]

Bug Description I make a NT4 subscription with an empty string "", prefix, and all, but the server doesn't send my subscription all the values currently recognized. All topics do get announced to the client, but only about 19 - 24 out of 36 actually have their current value sent to my client.

To Reproduce Steps to reproduce the behavior:

1. Subscribe with [""] and {"prefix": true, "all": true}
2. Not all values in the server are sent to the client

Expected behavior All currently recognized topic values are to be sent to a client that subscribes to all values when they subscribe.

Desktop:

• WPILib Version: 2023.2.1
• OS: MacOS 12.3
• Java version: 11

Additional context I am using my own implementation of the NT4 spec in this repo, although this shouldn't be affecting anything because everything else works as expected.

[PeterJohnson]

Upgrade to 2023.3.2. This should already be fixed there.

[tsar-boomba]

I updated to 2023.3.2, restarted my laptop, and updated my robot project to use 2023.3.2. However, I still have the same issue as before. Below is a screenshot of the problem and the subscription I'm using.

[PeterJohnson]

Do you have any other subscriptions already created before this subscription? Do all of the topics have values assigned on the server side?

[tsar-boomba]

This is the only subscription. The topics that I don't receive do have values, I've been working around this by restarting my client until I get the values I need.

[PeterJohnson]

Do you have a link to your robot project? I’m puzzled as to how this can be happening looking at the code that handles sending initial announcements and values.

[tsar-boomba]

This is the repo and branch I'm using https://github.com/Yeti-Robotics/aurora-java-2022/tree/development

[sciencewhiz]

That branch is still using 2023.1.1

[tsar-boomba]

Sorry, that is because I haven't pushed the change to 2023.3.2 in the build.gradle. On my machine, it is running 2023.3.3.2

[PeterJohnson]

So testing your robot program in simulation, there are no values being published to several published topics:

• /Shuffleboard/.metadata/Selected
• /Shuffleboard/.recording/FileNameFormat
• /Shuffleboard/.recording/RecordData
• /CameraPublisher/USB Camera 0/modes

The sim GUI NT view shows they don't have values, and no value is sent over the network.

I ran the C++ client with some WS debug-level logging turned on: https://gist.github.com/PeterJohnson/9796cab6a78438680383ebf96117fccc

I'm not sure why you're seeing a discrepancy of 16. I count 33 announced and 29 values sent in the above.

[tsar-boomba]

Alright, I'll look over my implementation, I must have missed something there. Thank you for your help!

[tsar-boomba]

Yeah, looks like a lot of values are being received before the server announces them, so I've gotta solve that now, thank you!

[PeterJohnson]

Huh? Values aren’t sent before they are announced (see the trace above, each announcement is followed by the value).

[tsar-boomba]

Yes, they are received in order, but I process messages asynchronously which is what caused the discrepancy. I'm definitely considering changing this behavior in the future, but for now, I have it worked out. Once again, thank you for your help.