DButils.addProcess: force empty output product to null (Closes #95)

 * This fixes processes with no output product on postgresql.

dbprocessing/DButils.py

@@ -902,7 +902,7 @@ def addProcess(self,
             raise ValueError("output_timebase invalid choice")
 
         p1 = self.Process()
-        p1.output_product = output_product
+        p1.output_product = Utils.toNone(output_product)
         p1.process_name = process_name
         p1.extra_params = Utils.toNone(extra_params)
         p1.output_timebase = output_timebase

unit_tests/test_DButils.py

@@ -83,6 +83,17 @@ def test_addMissionOptionals(self):
         self.assertEqual('/rootdir/errors', self.dbu.getErrorPath())
         self.assertEqual('/rootdir', self.dbu.getInspectorDirectory())
 
+    def test_addProcessNoOutput(self):
+        """Add a process with no output product"""
+        # This needs to be on "empty" db because our test non-empty
+        # doesn't allow null output product (old database)
+        pid = self.dbu.addProcess('no_output1', '', 'RUN')
+        self.assertIsNone(self.dbu.getEntry('Process', pid).output_product)
+        pid = self.dbu.addProcess('no_output2', None, 'RUN')
+        self.assertIsNone(self.dbu.getEntry('Process', pid).output_product)
+        pid = self.dbu.addProcess('no_output3', 0, 'RUN')
+        self.assertEqual(0, self.dbu.getEntry('Process', pid).output_product)
+
 
 class DBUtilsOtherTests(TestSetup):
     """Tests that are not processqueue or get or add"""