Added support for expanding environment variables in configuration files.

prestoadmin/config.py

@@ -53,6 +53,12 @@ def get_conf_from_properties_data(data):
         if len(line) > 0 and line[0] not in COMMENT_CHARS:
             pair = split_to_pair(line)
             props[pair[0]] = pair[1]
+    return expand_environment_variables(props)
+
+
+def expand_environment_variables(props):
+    for key in props:
+        props[key] = os.path.expandvars(props[key])
     return props
 
 

tests/unit/resources/environment_variable.properties

@@ -0,0 +1 @@
+a=${ENVIRONMENT_VARIABLE}

tests/unit/resources/valid.config

@@ -1,3 +1,4 @@
 prop1
 prop2
-prop3
+prop3
+${ENVIRONMENT_VARIABLE}

tests/unit/resources/valid.properties

@@ -9,4 +9,4 @@ f===6
 g:= 7
 h=:8
 i   = 9
-
+j=${ENVIRONMENT_VARIABLE}

tests/unit/test_config.py

@@ -58,14 +58,22 @@ def test_invalid_json(self):
     def test_get_config(self):
         config_file = os.path.join(DIR, 'resources', 'valid.config')
         conf = config.get_conf_from_config_file(config_file)
-        self.assertEqual(conf, ['prop1', 'prop2', 'prop3'])
+        self.assertEqual(conf, ['prop1', 'prop2', 'prop3', '${ENVIRONMENT_VARIABLE}'])
 
     def test_get_properties(self):
         config_file = os.path.join(DIR, 'resources', 'valid.properties')
         conf = config.get_conf_from_properties_file(config_file)
         self.assertEqual(conf, {'a': '1', 'b': '2', 'c': '3',
                                 'd\\=': '4', 'e\\:': '5', 'f': '==6',
-                                'g': '= 7', 'h': ':8', 'i': '9'})
+                                'g': '= 7', 'h': ':8', 'i': '9', 'j': '${ENVIRONMENT_VARIABLE}'})
+
+    @patch('prestoadmin.config.os.path.expandvars', return_value='environment_variable_value')
+    def test_expending_environment_variable(self, environment_variables):
+        config_file = os.path.join(DIR, 'resources', 'environment_variable.properties')
+        conf = config.get_conf_from_properties_file(config_file)
+        self.assertTrue(environment_variables.called)
+        self.assertEqual({'a': 'environment_variable_value'}, conf)
+
 
     @patch('__builtin__.open')
     def test_get_properties_ignores_whitespace(self, open_mock):