Implement ELBV2 add_tags endpoint

lib/fog/aws/elbv2.rb

@@ -5,6 +5,7 @@ module Fog
       recognizes :region, :host, :path, :port, :scheme, :persistent, :use_iam_profile, :aws_session_token, :aws_credentials_expire_at, :version, :instrumentor, :instrumentor_name
 
       request_path 'fog/aws/requests/elbv2'
+      request :add_tags
       request :create_load_balancer
       request :describe_load_balancers
       request :describe_listeners

lib/fog/aws/parsers/elbv2/empty.rb

@@ -0,0 +1,10 @@
+module Fog
+  module Parsers
+    module AWS
+      module ELBV2
+        class Empty < ELB::Empty
+        end
+      end
+    end
+  end
+end

lib/fog/aws/requests/elbv2/add_tags.rb

@@ -0,0 +1,45 @@
+module Fog
+  module AWS
+    class ELBV2
+      class Real
+        require 'fog/aws/parsers/elbv2/empty'
+
+        # adds tags to a load balancer instance
+        # http://docs.aws.amazon.com/ElasticLoadBalancing/latest/APIReference/API_AddTags.html
+        # ==== Parameters
+        # * resource_arn <~String> - The Amazon Resource Name (ARN) of the resource
+        # * tags <~Hash> A Hash of (String) key-value pairs
+        # ==== Returns
+        # * response<~Excon::Response>:
+        #   * body<~Hash>:
+        def add_tags(resource_arn, tags)
+          keys    = tags.keys.sort
+          values  = keys.map {|key| tags[key]}
+          request({
+              'Action'                     => 'AddTags',
+              'ResourceArns.member.1'      => resource_arn,
+              :parser                      => Fog::Parsers::AWS::ELBV2::Empty.new,
+            }.merge(Fog::AWS.indexed_param('Tags.member.%d.Key', keys))
+             .merge(Fog::AWS.indexed_param('Tags.member.%d.Value', values)))
+        end
+
+      end
+
+      class Mock
+        def add_tags(resource_arn, tags)
+          response = Excon::Response.new
+          if self.data[:load_balancers_v2][resource_arn]
+            self.data[:tags][resource_arn].merge! tags
+            response.status = 200
+            response.body = {
+              "ResponseMetadata"=>{ "RequestId"=> Fog::AWS::Mock.request_id }
+            }
+            response
+          else
+            raise Fog::AWS::ELBV2::NotFound.new("Elastic load balancer #{resource_arn} not found")
+          end
+        end
+      end
+    end
+  end
+end