It appears that whenever I make a call to a service through a URL to generate an image that the PDF does not wait for the response of the image before rendering.

Some more details on that is we are making a request to generate a map. The WMS will then kick back a png of the image that was requested. This all works perfectly fine when viewing the HTML. But there is some lag time as far as generating the image goes (up to 6 seconds). The PDF seems to not be waiting for the images to get returned to generate.

Is there any known bugs of this or is there an easy workaround to force the wait?

Prince should wait, can you run it with the --debug flag and check the log output when it attempts to retrieve the URL?

Running it with Debug was perfect. It was an incorrect MIME type because I was using & in html. Replaced with & and it worked fine.

Thanks for the quick response!