Routing error with post action

[PAMulligan]

When testing a controller with the following code:

post 'http://localhost:3000/api/v4/contacts/', { }, { 'params' => { user_id: '00055294-EE7E-4596-A868-BDD5A90BB51F',
									    name: 'Paul Mulligan',
									    address_1: '7320 15th Ave NW',
									    city: 'Seattle',
									    zip_code_5: '98117',
									    country: 'US'
									}
								}

I'm getting the following error:

ActionController::UrlGenerationError:
   No route matches {:action=>"http://localhost:3000/api/v4/contacts/", :controller=>"api/v4/contacts"}

I have my server running, and this action works with Postman. I'm using Rails 4.2.6 and rspec-rails 3.5.2.