We've just released Koken 0.20.3, which includes several minor fixes for issues our fine users have reported in the last several days. It also includes a notable fix for users of our Lightroom Publish Services plugin.
For some time, a portion of our Lightroom users have reported odd, intermittent behavior when uploading from the Lightroom plugin. Some uploads would work while others would not, accompanied by cryptic error messages. Further complicating matters was the fact that our team was unable to duplicate the issue on any of our numerous test installations.
Thanks to Koken user Jonathan Levy, we were finally able to get a reproducible form of the issue late last week. After some investigation, we traced the issue to something known as 'keep-alive' connections. When a server was using keep-alive connections, the first upload would work, but subsequent uploads would often fail due to how the connection was shared from the previous upload request. So, as of Koken 0.20.3, we now explicitly close the connection after each upload, which negates the effect of keep-alive connections and in turn resolves this problem.
For those of you who have been experiencing this issue, thank you for your patience. This is one of the challenges of self-hosted software, as it is often difficult to track down server specific issues like this one. We're glad to have this one behind us!