Add check for maximum URL length of a request

[googlemaps]

Add check for maximum URL length of a request

[stephenmcd]

Thanks for bringing this up.

We decided not to implement breaking long elevation requests into multiple parts since it could have unpredicatble costs against a user's quota. What I have done though is modified elevation requests to use polyline encoding which should result in much shorter URLs:

86e38dd

Could you give this a try and see how effective it is in your case?

[wwwald]

I hadn't thought of using encoded polylines in the URL, that already greatly increases the per-request bandwidth. Seems that 400-420 points in an encoded polyline is about the upper limit of points per request, opposed to 80-85 for unencoded lat/lng lists.

Completely agree on the current solution - it's best to have users work around possible URL length limitations and make them explicitly aware of the requests/quota implications.

[wwwald]

I'm currently down to a limit of 380 points per request, that seems to be a number that ensures that 99% of the polyline-encoded URLs stay within the URL length limit.

I haven't looked at the remaining 1% in detail, so it's unclear what exactly makes the polylines run longer in those cases.