Adding an "Affected Version" via Rest API

Hello, Rory!
Yes, it's possible. General steps are:

• Get custom filed with name "Affected version" from project: http://confluence.jetbrains.net/display/YTD4/GET+Project+Custom+Field
  
• Get it's bundle name (value of "param" element with "name" attribute set to bundle)
  
• Add new version to that bundle http://confluence.jetbrains.net/display/YTD4/Add+New+Version+to+Bundle
  

Thanks, Anna, I can mostly see how that would work, but if you would help me a bit more to understand I'd be grateful.

• I don't understand the concept of a "bundle". Is this like a list? So the "Affected Versions" field is a sort of list of version values?
  
• It doesn't appear that this functionality is present in the YouTrack .Net client, is this true?

Also, if you can point me in the direction of documentation for setting up REST on a hosted YouTrack instance, I'd really appreciate it. I'm having a hard time finding clear guidance on basic questions like these for version 4.0 of YouTrack when it is hosted.

Yes, bundle is a list of values, that can be used for custom field. You can go to Administration -> Your Project -> Fields tab. There is a list of custom fields there. You can click on bundle name in corresponding column and view\edit this this list of values.
What is your exact problem with setting up REST? In YouTrack REST API is always enabled. The only thing you need to know to use it - YouTrack base url. If you are using hosted YouTrack, it should be "http://<your instance name>.myjetbrains.com/youtrack".
I'm not sure about .Net client - I'm not sure now, I'll check this with my colleague.

Hi Anna -

Any luck determining if the .Net client supports adding versions to the versions bundle?

I checked the code in github. It didn't, but I added it. I'm close to having it working, but the adding is failing. Do you know if the REST verb needs to be PUT or can it be POST?

I figured it out. It looks like a limitation in the EasyHttp library used to make HTTP requests. I came up with a workaround and sent a pull request to https://github.com/JetBrains/YouTrackSharp.