The Bing Maps Snap to Road API can take in one or more coordinates and retrieve the speed limit for that section of road. The coordinate returned will most likely be different than what you passed in as this API "snaps" it to the road line used in the map while your input is likely a GPS coordinate that could be a meter or two away.
There is no API that I am aware of that turned the number of turns in a route path. That said, I had a similar need many years ago for a project and I ended up writing some code that analyzed the snapped route line. I don't have the code any longer, but here is what it did:
- Step through each coordinate in the route path and calculate the heading (or bearing) between coordinates.
- Look through the heading and calculate the angle difference between them. A 90-degree change in heading is likely to be too strict for this analysis and depending on your scenario (not uncommon for forks in a road to be much less than 90-degrees), so you need to decide what angle change you want to use to consider a change in a direction a turn.