Merge pull request #87 from sul-cidr/reraise#82

Closes #82. Re-raise exceptions properly in the pipeline command

histonets/cli.py

@@ -71,7 +71,10 @@ def pipeline(image, actions):
             raise click.BadParameter(
                 "Action '{}' not found".format(action['action']))
         options['output'] = RAW
-        output = command.callback(*arguments, **options)
+        try:
+            output = command.callback(*arguments, **options)
+        except TypeError as e:
+            raise click.BadParameter(e)
     return output
 
 

tests/test_cli.py

@@ -237,6 +237,16 @@ def test_command_pipeline_invalid(self):
         assert 'Error' in result.output
         assert len(result.output.strip()) > 0
 
+    def test_command_pipeline_reraise_error(self):
+        actions = json.dumps([
+            {"action": "posterize", "options":
+                {"value": 4, "method": "linear"}}
+        ])
+        result = self.runner.invoke(cli.pipeline, [actions, self.image_file])
+        assert 'Error' in result.output
+        assert not isinstance(result.exception, TypeError)
+        assert len(result.output.strip()) > 0
+
     def test_command_posterize_linear(self):
         result = self.runner.invoke(
             cli.posterize,