HTTP trigger azure function won't bind route parameter with encoded slashes

Question

I've created an Azure C# HTTP triggered function with a route url: subscriptions/{token}/t. It works fine for urls such as subscriptions/blah/t but it fails with a 404 for parameters that contain encoded slashes: subscriptions/blah%2fblah/t. Any way around this ?

Before we get into debates, {token} is a URL encoded Base64 string which will naturally contain slashes.

Answer 1

This issue seems to persist. I found out that it can be resolved by double-escaping the string, that is, applying escaping recursively two times.

token = escape(escape(token));

In .NET you can use URI.EsacpeDataString()
In JS you can use encodeURIComponent()

Note, that single escaping does not work reliably with Azure functions