Output File CLI Option (#1511)

* --output-file CLI argument added

Co-authored-by: Kevin DeJong <[email protected]>

src/cfnlint/__main__.py

@@ -37,8 +37,14 @@ def main():
             LOGGER.debug('Completed linting of file: %s', str(filename))
 
         matches_output = formatter.print_matches(matches, rules)
+
         if matches_output:
-            print(matches_output)
+            if args.output_file:
+                with open(args.output_file, 'w') as output_file:
+                    output_file.write(matches_output)
+            else:
+                print(matches_output)
+
         return cfnlint.core.get_exit_code(matches)
     except cfnlint.core.CfnLintExitException as e:
         LOGGER.error(str(e))

src/cfnlint/config.py

@@ -426,6 +426,11 @@ def __call__(self, parser, namespace, values, option_string=None):
             action='store_true'
         )
 
+        standard.add_argument(
+            '--output-file', type=str, default=None,
+            help='Writes the output to the specified file, ideal for producing reports'
+        )
+
         return parser
 
 
@@ -655,3 +660,8 @@ def config_file(self):
     def build_graph(self):
         """ build_graph """
         return self._get_argument_value('build_graph', False, False)
+
+    @property
+    def output_file(self):
+        """ output_file """
+        return self._get_argument_value('output_file', False, True)

src/cfnlint/data/CfnLintCli/config/schema.json

@@ -38,6 +38,10 @@
       "description": "Path to spec file to override with",
       "type": "string"
     },
+    "output_file": {
+      "description": "Path to the file to write the main output to",
+      "type": "string"
+    },
     "regions": {
       "description": "Regions to test against",
       "items": {

test/unit/module/config/test_cli_args.py

@@ -38,6 +38,18 @@ def test_create_parser_default_param(self):
         self.assertEqual(config.cli_args.template_alt, [])
         self.assertEqual(config.cli_args.regions, ['us-east-1', 'us-west-2'])
 
+    def test_stdout(self):
+        """Test success run"""
+
+        config = cfnlint.config.CliArgs(['-t', 'template1.yaml'])
+        self.assertIsNone(config.cli_args.output_file)
+
+    def test_output_file(self):
+        """Test success run"""
+
+        config = cfnlint.config.CliArgs(['-t', 'template1.yaml', '--output-file', 'test_output.txt'])
+        self.assertEqual(config.cli_args.output_file, 'test_output.txt')
+
     def test_create_parser_exend(self):
         """Test success run"""
 

test/unit/module/config/test_config_mixin.py

@@ -59,6 +59,36 @@ def test_config_precedence(self, yaml_mock):
         # template file wins over config file
         self.assertEqual(config.ignore_checks, ['W3001'])
 
+    @patch('cfnlint.config.ConfigFileArgs._read_config', create=True)
+    def test_config_file_output(self, yaml_mock):
+        """ Test precedence in  """
+
+        yaml_mock.side_effect = [
+            {
+                "output_file": "test_output.txt"
+            },
+            {}
+        ]
+        config = cfnlint.config.ConfigMixIn([])
+
+        # Config file wins
+        self.assertEqual(config.output_file, 'test_output.txt')
+
+    @patch('cfnlint.config.ConfigFileArgs._read_config', create=True)
+    def test_config_file_output_mixin(self, yaml_mock):
+        """ Test precedence in  """
+
+        yaml_mock.side_effect = [
+            {
+                "output_file": "test_output.txt"
+            },
+            {}
+        ]
+        config = cfnlint.config.ConfigMixIn(['--output-file', 'test_output_2.txt'])
+
+        # CLI args win
+        self.assertEqual(config.output_file, 'test_output_2.txt')
+
     @patch('cfnlint.config.ConfigFileArgs._read_config', create=True)
     def test_config_default_region(self, yaml_mock):
         """ Test precedence in  """

test/unit/module/core/test_run_cli.py

@@ -130,6 +130,14 @@ def test_template_config(self, yaml_mock):
                          'test/fixtures/templates/good/core/config_parameters.yaml'])
         self.assertEqual(args.update_documentation, False)
         self.assertEqual(args.update_specs, False)
+        self.assertEqual(args.output_file, None)
+
+    def test_output_file(self):
+        filename = 'test/fixtures/templates/good/core/config_parameters.yaml'
+        (args, _, _,) = cfnlint.core.get_args_filenames([
+            '--template', filename, '--output-file', 'test_output.txt'])
+
+        self.assertEqual(args.output_file, 'test_output.txt')
 
     @patch('cfnlint.config.ConfigFileArgs._read_config', create=True)
     def test_positional_template_parameters(self, yaml_mock):