Replace usage of assert by explicit exceptions (fixes #592)

CHANGELOG.rst

@@ -24,6 +24,9 @@ This document describes changes between each past release.
 
 - Fixed a few details in quickstart docs since backends are not Redis by default
   anymore
+- Replace usage of ``assert`` by explicit exceptions since the former can
+  be ignored when python is ran with ``-O`` (fixes #592)
+
 
 2.11.0 (2015-11-17)
 -------------------

cliquet/resource/__init__.py

@@ -705,9 +705,10 @@ def _raise_304_if_not_modified(self, record=None):
         if_none_match = decode_header(if_none_match)
 
         try:
-            assert if_none_match[0] == if_none_match[-1] == '"'
+            if not (if_none_match[0] == if_none_match[-1] == '"'):
+                raise ValueError()
             modified_since = int(if_none_match[1:-1])
-        except (IndexError, AssertionError, ValueError):
+        except (IndexError, ValueError):
             if if_none_match != '*':
                 error_details = {
                     'location': 'headers',
@@ -744,9 +745,10 @@ def _raise_412_if_modified(self, record=None):
             modified_since = -1  # Always raise.
         elif if_match:
             try:
-                assert if_match[0] == if_match[-1] == '"'
+                if not (if_match[0] == if_match[-1] == '"'):
+                    raise ValueError()
                 modified_since = int(if_match[1:-1])
-            except (IndexError, AssertionError, ValueError):
+            except (IndexError, ValueError):
                 message = ("Invalid value for If-Match. The value should "
                            "be integer between double quotes.")
                 error_details = {
@@ -957,10 +959,11 @@ def _extract_pagination_rules_from_token(self, limit, sorting):
         if token:
             try:
                 tokeninfo = json.loads(decode64(token))
-                assert isinstance(tokeninfo, dict)
+                if not isinstance(tokeninfo, dict):
+                    raise ValueError()
                 last_record = tokeninfo['last_record']
                 offset = tokeninfo['offset']
-            except (ValueError, KeyError, TypeError, AssertionError):
+            except (ValueError, KeyError, TypeError):
                 error_msg = '_token has invalid content'
                 error_details = {
                     'location': 'querystring',

cliquet/storage/postgresql/__init__.py

@@ -108,7 +108,8 @@ def initialize_schema(self):
             expected = migration[0]
             current = self._get_installed_version()
             error_msg = "Expected version %s. Found version %s."
-            assert expected == current, error_msg % (expected, current)
+            if expected != current:
+                raise AssertionError(error_msg % (expected, current))
 
             logger.info('Migrate schema from version %s to %s.' % migration)
             filepath = 'migration_%03d_%03d.sql' % migration
@@ -139,7 +140,8 @@ def _check_database_encoding(self):
             result = conn.execute(query)
             record = result.fetchone()
         encoding = record['encoding'].lower()
-        assert encoding == 'utf8', 'Unexpected database encoding %s' % encoding
+        if encoding != 'utf8':  # pragma: no cover
+            raise AssertionError('Unexpected database encoding %s' % encoding)
 
     def _get_installed_version(self):
         """Return current version of schema or None if not any found.