[Brightbox] Extracts parts of request out of compute

* Adds simple helper to get token for service
* Low level request #request_access_token is provided to request
  access tokens

lib/fog/brightbox/compute.rb

@@ -276,38 +276,37 @@ module Fog
           @credentials.refresh_token
         end
 
-      private
-
-        def get_oauth_token
-          if authenticating_as_user?
-            token_strategy = UserCredentialsStrategy.new(@credentials)
-          else
-            token_strategy = ClientCredentialsStrategy.new(@credentials)
+        # Requests a new access token
+        #
+        # @return [String] New access token
+        def get_access_token
+          begin
+            get_access_token!
+          rescue Excon::Errors::Unauthorized, Excon::Errors::BadRequest
+            @credentials.update_tokens(nil, nil)
           end
-
-          basic_header_to_encode = "#{@credentials.client_id}:#{@credentials.client_secret}"
-
-          response = @auth_connection.request({
-            :path => "/token",
-            :expects  => 200,
-            :headers  => {
-              'Authorization' => "Basic " + Base64.encode64(basic_header_to_encode).chomp,
-              'Content-Type' => 'application/json'
-            },
-            :method   => 'POST',
-            :body     => Fog::JSON.encode(token_strategy.authorization_body_data)
-          })
-          response_data = Fog::JSON.decode(response.body)
-          @credentials.update_tokens(response_data["access_token"], response_data["refresh_token"])
           @credentials.access_token
         end
 
+        # Requests a new access token and raises if there is a problem
+        #
+        # @return [String] New access token
+        # @raise [Excon::Errors::BadRequest] The credentials are expired or incorrect
+        #
+        def get_access_token!
+          response = request_access_token(@auth_connection, @credentials)
+          update_credentials_from_response(@credentials, response)
+          @credentials.access_token
+        end
+
+      private
+
         def make_request(params)
           begin
-            get_oauth_token unless access_token_available?
+            get_access_token unless access_token_available?
             response = authenticated_request(params)
           rescue Excon::Errors::Unauthorized
-            get_oauth_token
+            get_access_token
             response = authenticated_request(params)
           end
           unless response.body.empty?

lib/fog/brightbox/oauth2.rb

@@ -5,6 +5,31 @@
 #
 module Fog::Brightbox::OAuth2
 
+  # This builds the simplest form of requesting an access token
+  # based on the arguments passed in
+  #
+  # @param [Fog::Connection] connection
+  # @param [CredentialSet] credentials
+  #
+  # @return [Excon::Response]
+  def request_access_token(connection, credentials)
+    token_strategy = credentials.best_grant_strategy
+
+    header_content = "#{credentials.client_id}:#{credentials.client_secret}"
+    encoded_credentials = Base64.encode64(header_content).chomp
+
+    connection.request({
+      :path => "/token",
+      :expects  => 200,
+      :headers  => {
+        'Authorization' => "Basic #{encoded_credentials}",
+        'Content-Type' => 'application/json'
+      },
+      :method   => 'POST',
+      :body     => Fog::JSON.encode(token_strategy.authorization_body_data)
+    })
+  end
+
   # Encapsulates credentials required to request access tokens from the
   # Brightbox authorisation servers
   #
@@ -50,6 +75,18 @@ module Fog::Brightbox::OAuth2
       @access_token  = access_token
       @refresh_token = refresh_token
     end
+
+    # Based on available credentials returns the best strategy
+    #
+    # @todo Add a means to dictate which should or shouldn't be used
+    #
+    def best_grant_strategy
+      if user_details?
+        UserCredentialsStrategy.new(self)
+      else
+        ClientCredentialsStrategy.new(self)
+      end
+    end
   end
 
   # This strategy class is the basis for OAuth2 grant types
@@ -97,4 +134,16 @@ module Fog::Brightbox::OAuth2
       }
     end
   end
+
+private
+
+  # This updates the current credentials if passed a valid response
+  #
+  # @param [CredentialSet] credentials Credentials to update
+  # @param [Excon::Response] response Response object to parse value from
+  #
+  def update_credentials_from_response(credentials, response)
+    response_data = Fog::JSON.decode(response.body)
+    credentials.update_tokens(response_data["access_token"], response_data["refresh_token"])
+  end
 end

tests/brightbox/oauth2_tests.rb

@@ -13,6 +13,9 @@ Shindo.tests("Fog::Brightbox::OAuth2", ["brightbox"]) do
       tests("#user_details?").returns(false) { credentials.user_details? }
       tests("#access_token?").returns(false) { credentials.access_token? }
       tests("#refresh_token?").returns(false) { credentials.refresh_token? }
+      tests("#best_grant_strategy").returns(true) do
+        credentials.best_grant_strategy.is_a?(Fog::Brightbox::OAuth2::ClientCredentialsStrategy)
+      end
     end
 
     tests("with user credentials") do
@@ -21,14 +24,9 @@ Shindo.tests("Fog::Brightbox::OAuth2", ["brightbox"]) do
       tests("#user_details?").returns(true) { credentials.user_details? }
       tests("#access_token?").returns(false) { credentials.access_token? }
       tests("#refresh_token?").returns(false) { credentials.refresh_token? }
-    end
-
-    tests("with existing tokens") do
-      options = {:username => @username, :access_token => @access_token, :refresh_token => @refresh_token}
-      credentials = Fog::Brightbox::OAuth2::CredentialSet.new(@client_id, @client_secret, options)
-      tests("#user_details?").returns(false) { credentials.user_details? }
-      tests("#access_token?").returns(true) { credentials.access_token? }
-      tests("#refresh_token?").returns(true) { credentials.refresh_token? }
+      tests("#best_grant_strategy").returns(true) do
+        credentials.best_grant_strategy.is_a?(Fog::Brightbox::OAuth2::UserCredentialsStrategy)
+      end
     end
   end