ArcGIS Server 10.2.2 - Map Export Sometimes Returns Blank Image

Question

I've run into a fun little issue with ArcGIS Server 10.2.2 to end my week with... I have discovered today that the export operation (the one that renders map layer images) is randomly returning blank images. As in - I enter a export url into the browser, hit F5, get expected image. Hit F5 again - get blank image. Hit F5 again - get expected image. None of the parameters are changing - its exact same url. There is no observable pattern - sometimes I got to hit F5 multiple times before I get expected image.

I remember facing a similar bug back at 10.1 - where every other GET query failed (How does that make it through testing???). This seems awfully similar to that. I starting search GeoNet - and have seen similar posts. Does anyone know if there is any official NIM for this issue - and more importantly a solution or workaround?

Answer 1

The solution on the JavaScript API side is to intercept the request to export map by passing a handler function to esriRequest.setRequestPreCallback like explained here

https://developers.arcgis.com/javascript/jsapi/esri.request-amd.html#esrirequest.setrequestprecallback

Check if ioArgs.url ends with "MapServer/export"

If yes, then set ioArgs.content.random to Math.random()