GixyBear.py: Add GixyBear

This commit adds GixyBear.

Closes coala#1724

bears/configfiles/GixyBear.py

@@ -0,0 +1,30 @@
+from coalib.bearlib.abstractions.Linter import linter
+from coalib.results.RESULT_SEVERITY import RESULT_SEVERITY
+from coalib.results.Result import Result
+import json
+
+
+@linter(executable='gixy')
+class GixyBear:
+    """
+    A wrapper for coala around Gixy
+    
+    see <https://github.com/yandex/gixy> for more information about the tool
+    """
+    REQUIREMENTS={PipRequirement('gixy', '0.1.*')}
+
+    severity_map = {'HIGH': RESULT_SEVERITY.MAJOR,
+                    'MEDIUM': RESULT_SEVERITY.NORMAL,
+                    'LOW': RESULT_SEVERITY.INFO}
+
+    @staticmethod
+    def create_arguments(filename, file, config_file):
+        return ('--format=json', filename)
+
+    def process_output(self, output, filename, file):
+        output = json.loads(output) if output else []
+        for issue in output:
+            yield Result.from_values(origin=self,
+                                message=issue['summary'],
+                                severity=self.severity_map[issue['severity']],
+                                file=filename)

tests/configfiles/GixyBearTest.py

@@ -0,0 +1,26 @@
+import os
+
+from bears.configfiles.GixyBear import GixyBear
+from coalib.testing.LocalBearTestHelper import verify_local_bear
+
+good_file = """
+server {
+    location ~ \.(gif|jpg|png)$ {
+        root /data/images;
+    }
+}
+"""
+
+bad_file = """
+http{
+  server{
+    location ~ /proxy/(.*)/(.*)/(.*)$ {
+      proxy_pass $1://$2/$3;
+    }
+  }
+}
+"""
+
+GixyBearTest = verify_local_bear(GixyBear,
+                                 valid_files = (good_file, ),
+                                 invalid_files = (bad_file, ))