What approach should I use to enable a customer to deploy content (just items) from their CM environment to a CD environment, where the CD environment would not allow any SQL ports through the firewall? Something like zipping up a package or serialization files, uploading that over HTTP, unpacking and installing it, and then clearing caches? It would be even better if this could be a single SQL transaction. Has anyone ever done anything like this? Maybe I'm missing something obvious. Could TDS, Sitecore Ship, Unicorn, SSC, or anything else assist here?
Because the customer might want to use the publishing service (https://dev.sitecore.net/Downloads/Sitecore_Publishing_Service.aspx) after they get to 8.2, any solution probably not depend on publishing pipelines. I'm not familiar enough with any of these technologies to make a recommendation.
Feel free to tell me to RSomeFM or blog posts or something. I would be happy to do some development; mostly looking for architectural and toolset suggestions.