import openapi: fix when missing operation id in spec

lib/3scale_toolbox/commands/import_command/openapi/method.rb

@@ -12,12 +12,16 @@ def method
           end
 
           def friendly_name
-            operation[:operationId]
+            operation[:operationId] || operation_id
           end
 
           def system_name
             friendly_name.downcase
           end
+
+          def operation_id
+            "#{operation[:verb]}#{operation[:path].gsub(/[^\w]/, '')}"
+          end
         end
       end
     end

spec/unit/commands/import_command/openapi/method_spec.rb

@@ -22,4 +22,18 @@ def initialize(operation)
       is_expected.to include('system_name' => operationId.downcase)
     end
   end
+
+  context 'operation id not available' do
+    let(:operation) { { verb: 'get', path: '/pet/{petId}' } }
+
+    subject { OpenAPIMethodClass.new(operation).method }
+
+    it 'contains "friendly_name"' do
+      is_expected.to include('friendly_name' => 'getpetpetId')
+    end
+
+    it 'contains "system_name"' do
+      is_expected.to include('system_name' => 'getpetpetid')
+    end
+  end
 end