When trying to configure an Azure Front Door Standard (preview) with an API Origin and a static content origin the Rule engine I came across an issue not allowing me full freedom in rewriting paths.
Using two origins and two routes with path selectors whereas one has a 'fall-thru' /* and the other has /api and /api/* defined the requests from the front-end route to the correct origin.
However, there is a need to do some rewriting of the paths for those requests that match /api/* so a rule set is created attached to that route. However even the most basic rewrite fails. Doing some digging it appears that the URL Path on which the rewrite logic is likely to be performed is missing its leading slash, and setting a Source pattern without leading slash is not allowed.
To ensure there are configurations wherein it is working as expected I also created another configuration which is indeed working as expected (albeit non useful in my situation).
Attached some screenshots of both the working (but useless) and non-working configurations and some evidence (App Insights at the Origin) thereof.
Am I alone in this behavior, is there something I overlooked or is this a bug in the service itself?
Non-working config and evidence