Drop eval-based json parser fallback

Drop potentially-unsafe eval-based json parser that was
used as a fallback in case simplejson and json were not
available. Let's assume people run Python 2.6 or can
install simplejson if they are not. Fixes bug 909568.

Change-Id: I1b1860a77de5075fcea291a4f1b320a3e9e6261f

bin/swift

@@ -71,38 +71,9 @@ try:
     from simplejson import loads as json_loads
     from simplejson import dumps as json_dumps
 except ImportError:
-    try:
     # 2.6 will have a json module in the stdlib
     from json import loads as json_loads
     from json import dumps as json_dumps
-    except ImportError:
-        # fall back on local parser otherwise
-        comments = compile(r'/\*.*\*/|//[^\r\n]*', DOTALL)
-
-        def json_loads(string):
-            '''
-            Fairly competent json parser exploiting the python tokenizer and
-            eval(). -- From python-cloudfiles
-
-            _loads(serialized_json) -> object
-            '''
-            try:
-                res = []
-                consts = {'true': True, 'false': False, 'null': None}
-                string = '(' + comments.sub('', string) + ')'
-                for type, val, _junk, _junk, _junk in \
-                        generate_tokens(StringIO(string).readline):
-                    if (type == OP and val not in '[]{}:,()-') or \
-                            (type == NAME and val not in consts):
-                        raise AttributeError()
-                    elif type == STRING:
-                        res.append('u')
-                        res.append(val.replace('\\/', '/'))
-                    else:
-                        res.append(val)
-                return eval(''.join(res), {}, consts)
-            except Exception:
-                raise AttributeError()
 
 
 class ClientException(Exception):

swift/common/client.py

@@ -57,37 +57,8 @@ try:
     # simplejson is popular and pretty good
     from simplejson import loads as json_loads
 except ImportError:
-    try:
     # 2.6 will have a json module in the stdlib
     from json import loads as json_loads
-    except ImportError:
-        # fall back on local parser otherwise
-        comments = compile(r'/\*.*\*/|//[^\r\n]*', DOTALL)
-
-        def json_loads(string):
-            '''
-            Fairly competent json parser exploiting the python tokenizer and
-            eval(). -- From python-cloudfiles
-
-            _loads(serialized_json) -> object
-            '''
-            try:
-                res = []
-                consts = {'true': True, 'false': False, 'null': None}
-                string = '(' + comments.sub('', string) + ')'
-                for type, val, _junk, _junk, _junk in \
-                        generate_tokens(StringIO(string).readline):
-                    if (type == OP and val not in '[]{}:,()-') or \
-                            (type == NAME and val not in consts):
-                        raise AttributeError()
-                    elif type == STRING:
-                        res.append('u')
-                        res.append(val.replace('\\/', '/'))
-                    else:
-                        res.append(val)
-                return eval(''.join(res), {}, consts)
-            except Exception:
-                raise AttributeError()
 
 
 class ClientException(Exception):

test/unit/common/test_client.py

@@ -109,45 +109,6 @@ class TestJsonImport(unittest.TestCase):
         else:
             self.assertEquals(loads, c.json_loads)
 
-    def test_no_json(self):
-        # first break simplejson
-        try:
-            import simplejson
-        except ImportError:
-            # not installed, so we don't have to break it for these tests
-            pass
-        else:
-            delattr(simplejson, 'loads')
-
-        # then break json
-        try:
-            import json
-        except ImportError:
-            # not installed, so we don't have to break it for these tests
-            _orig_dumps = None
-        else:
-            # before we break json, grab a copy of the orig_dumps function
-            _orig_dumps = json.dumps
-            delattr(json, 'loads')
-            reload(c)
-
-        if _orig_dumps:
-            # basic test of swift.common.client.json_loads using json.loads
-            data = {
-                'string': 'value',
-                'int': 0,
-                'bool': True,
-                'none': None,
-            }
-            json_string = _orig_dumps(data)
-        else:
-            # even more basic test using a hand encoded json string
-            data = ['value1', 'value2']
-            json_string = "['value1', 'value2']"
-
-        self.assertEquals(data, c.json_loads(json_string))
-        self.assertRaises(AttributeError, c.json_loads, self)
-
 
 class MockHttpTest(unittest.TestCase):