vagrant virtualbox cannot make a POST request to a local rails app

vagrant virtualbox cannot make a POST request to a local rails app

I have a rails app running locally on port 3000.
From an app on Vagrant:
Requests::post( 'http://0.0.0.0:3000', $header, $payload );
Response:
'Cannot connect to host'
Note: When I run the same code out of the context of Vagrant, it works
perfectly.