Add job flow role to configuration

lib/elasticity/job_flow.rb

@@ -22,6 +22,7 @@ class JobFlow
     attr_accessor :region
     attr_accessor :visible_to_all_users
     attr_accessor :enable_debugging
+    attr_accessor :job_flow_role
 
     attr_reader :access_key
     attr_reader :secret_key
@@ -185,6 +186,7 @@ def jobflow_config
       steps.insert(0, Elasticity::SetupHadoopDebuggingStep.new.to_aws_step(self)) if @enable_debugging
       config[:steps] = steps
       config[:log_uri] = @log_uri if @log_uri
+      config[:job_flow_role] = @job_flow_role if @job_flow_role
       config[:bootstrap_actions] = @bootstrap_actions.map{|a| a.to_aws_bootstrap_action} unless @bootstrap_actions.empty?
       config
     end
@@ -229,4 +231,4 @@ def jobflow_instance_groups
 
   end
 
-end
+end

spec/lib/elasticity/job_flow_spec.rb

@@ -344,6 +344,32 @@
 
     end
 
+    describe 'job flow role' do
+
+      context 'when a job flow role is specified' do
+        let(:jobflow_with_job_flow_role) do
+          Elasticity::JobFlow.new('_', '_').tap do |jf|
+            jf.job_flow_role = 'JOB_FLOW_ROLE'
+          end
+        end
+        it 'should incorporate it into the jobflow config' do
+          jobflow_with_job_flow_role.send(:jobflow_config).should be_a_hash_including({:job_flow_role => 'JOB_FLOW_ROLE'})
+        end
+      end
+
+      context 'when a log URI is not specified' do
+        let(:jobflow_with_no_job_flow_role) do
+          Elasticity::JobFlow.new('_', '_').tap do |jf|
+            jf.job_flow_role = nil
+          end
+        end
+        it 'should not make space for it in the jobflow config' do
+          jobflow_with_no_job_flow_role.send(:jobflow_config).should_not have_key(:job_flow_role)
+        end
+      end
+
+    end
+
     describe 'bootstrap actions' do
 
       context 'when bootstrap actions are specified' do
@@ -686,4 +712,4 @@
 
   end
 
-end
+end