title: Adding a new Card in Stripe using Rails always says Missing required param: source
body: <p>I'm really stuck as to why I can't get this error to leave me be!</p>
  
  <p>I'm trying to add a new card to an existing user through the Stripe API, the Stripe Gem and stripe.js</p>
  
  <p>Server Log: (i've truncated values since the hashes are quite long):</p>
  
  <pre><code>Started PATCH "/users/11/billing" for xxx.xxx.xxx.xxx at 2016-01-09 05:47:50     +0000
  Processing by UsersController#update_billing as HTML
  Parameters: {"utf8"=&gt;"✓",   "authenticity_token"=&gt;"kKgMt...ItQ==", "user"=&gt;  {"stripe_card_token"=&gt;"tok_17RFZpHrpi1EikTto5nCO0", "plan_id"=&gt;""}, "id"=&gt;"11"}
  Stripe error while updating card info: Missing required param: source.
  </code></pre>
  
  <p>User.rb method:</p>
  
  <pre><code>def update_card(subscriber, stripe_card_token)
    # customer is created correctly
    customer = Stripe::Customer.retrieve(subscriber.stripeid)
    puts customer
    customer.sources.create(:source =&gt; stripe_card_token)
    customer.save
    rescue Stripe::InvalidRequestError =&gt; e
      logger.error "Stripe error while updating card info: #{e.message}"
      errors.add :base, "#{e.message}"
      false
  end
  </code></pre>
  
  <p>returned customer (from the puts customer)</p>
  
  <pre><code>{
   "id": "cus_7gCrNNYh3QWYyB",
   "object": "customer",
   "account_balance": 0,
   "created": 1452221885,
   "currency": "usd",
   "default_source": "card_17QqS0Hrpi1EikTtuQ24pf",
   "delinquent": false,
   "description": null,
   "discount": null,
   "email": "merp@merp.com",
   "livemode": false,
   "metadata": {},
   "shipping": null,
   "sources": {
      "object": "list",
      "data": [
         {
            "id": "card_17QqS0Hrpi1EikTtuQ24pf",
            "object": "card",
            "address_city": null,
            "address_country": null,
            "address_line1": null,
            "address_line1_check": null,
            "address_line2": null,
            "address_state": null,
            "address_zip": null,
            "address_zip_check": null,
            "brand": "Visa",
            "country": "US",
            "customer": "cus_7gCrNNYh3QWY",
            "cvc_check": "pass",
            "dynamic_last4": null,
            "exp_month": 1,
            "exp_year": 2016,
            "fingerprint": "W6mF0Trq946uDH",
            "funding": "credit",
            "last4": "4242",
            "metadata": {},
            "name": null,
            "tokenization_method": null
         }
      ],
      "has_more": false,
      "total_count": 1,
      "url": "/v1/customers/cus_7gCrNNYh3QWY/sources"
   },
   "subscriptions": {
      "object": "list",
      "data": [
         {
            "id": "sub_7gCrMFXaDTb6",
            "object": "subscription",
            "application_fee_percent": null,
            "cancel_at_period_end": false,
            "canceled_at": null,
            "current_period_end": 1483844285,
            "current_period_start": 1452221885,
            "customer": "cus_7gCrNNYh3QWY",
            "discount": null,
            "ended_at": null,
            "metadata": {},
            "plan": {
               "id": "2",
               "object": "plan",
               "amount": 12000,
               "created": 1451801067,
               "currency": "usd",
               "interval": "year",
               "interval_count": 1,
               "livemode": false,
               "metadata": {},
               "name": "Business Plan",
               "statement_descriptor": "Business Plan",
               "trial_period_days": null
            },
            "quantity": 1,
            "start": 1452221885,
            "status": "active",
            "tax_percent": null,
            "trial_end": null,
            "trial_start": null
         }
      ],
      "has_more": false,
      "total_count": 1,
      "url": "/v1/customers/cus_7gCrNNYh3QWY/subscriptions"
   }
  }
  </code></pre>
  
  <p>Some notes that I've checked:</p>
  
  <p>I get the same error before and after I've updated the STRIPE API
  I'm on the most recent Stripe API version (2015-10-16)
  The stripe gem is version 1.3.1 (October 29, 2015)
  Rails 4.2.2</p>