Ok, It’s been a week since I tried switching from Summary cards to Gallery cards, and I’ve gotten zero response from Twitter about why the Card Validator gives me System Errors and Timeouts, so I thought I’d play with it a little more.
I tried going back to Summary and the Validator says fine & dandy. Ok.
I went to Gallery again but with only image0, no image1 image2 or image3. That does give a result, with the missing tags pointed out. Ah hah! Looking at my web log, it seems that the Validator is fetching the four images, and I guess those four fetches plus the initial HTML fetch all have to complete within its three second timeout. I wouldn’t think that would be a problem, I have a nice fast web server and a reasonably wide data pipe, but indications are that there is some sort of bandwidth problem here.
I tried switching to thumbnail images instead of the medium-sized ones I want. That lets Validator give a result, although it’s not quite what I expected - it says everything is fine except that it can’t fetch image1. I don’t see anything different about that one vs. the other three images. In fact when I change the value of image1 to be the same as image2, Validator still says it can’t fetch image1 but image2 is fine. This is pretty weird.
Anyway I guess I’m closer to getting this to work.