I'm trying to use Tasker to shorten URLs. Previously, I don't think this was possible, but v1.3 added support for https.
I've tried following the instructions here: https://developers.google.com/url-shortener/v1/getting_started#shorten and I did get an HTTP 400 code, but the %HTTPD variable returned %HTTPD.
The things I used in Tasker were:
HTTP Post
Server:Port https://www.googleapis.com/urlshortener/v1/url?key=AIzaSyA8FwOcH-qW6ACR27H_wlrNKcv2OUl_Z8c
Data / File "longUrl":"http://www.google.com/"
Content Type application/json
Flash
Text %HTTPR
Flash
Text %HTTPD