Fixed #21189: Cleaned up usage of bare except clauses.

Thanks to berkerpeksag for the report and to claudep
for the review.

django/contrib/flatpages/middleware.py

@@ -12,7 +12,7 @@ class FlatpageFallbackMiddleware(object):
         # is a middleware, we can't assume the errors will be caught elsewhere.
         except Http404:
             return response
-        except:
+        except Exception:
             if settings.DEBUG:
                 raise
             return response

django/contrib/gis/db/backends/base.py

@@ -345,5 +345,5 @@ class SpatialRefSysMixin(object):
         """
         try:
             return six.text_type(self.srs)
-        except:
+        except Exception:
             return six.text_type(self.wkt)

django/contrib/gis/db/backends/spatialite/operations.py

@@ -238,15 +238,12 @@ class SpatiaLiteOperations(DatabaseOperations, BaseSpatialOperations):
         """
         Helper routine for calling SpatiaLite functions and returning
         their result.
+        Any error occuring in this method should be handled by the caller.
         """
         cursor = self.connection._cursor()
         try:
-            try:
-                cursor.execute('SELECT %s' % func)
-                row = cursor.fetchone()
-            except:
-                # Responsibility of caller to perform error handling.
-                raise
+            cursor.execute('SELECT %s' % func)
+            row = cursor.fetchone()
         finally:
             cursor.close()
         return row[0]

django/contrib/gis/forms/fields.py

@@ -73,7 +73,7 @@ class GeometryField(forms.Field):
             elif self.srid != -1 and self.srid != geom.srid:
                 try:
                     geom.transform(self.srid)
-                except:
+                except GEOSException:
                     raise forms.ValidationError(self.error_messages['transform_error'], code='transform_error')
 
         return geom

django/contrib/gis/geoip/__init__.py

@@ -14,5 +14,5 @@
 try:
     from .base import GeoIP, GeoIPException
     HAS_GEOIP = True
-except:
+except ImportError:
     HAS_GEOIP = False

django/contrib/gis/geos/libgeos.py

@@ -65,7 +65,7 @@ def notice_h(fmt, lst):
     fmt, lst = fmt.decode(), lst.decode()
     try:
         warn_msg = fmt % lst
-    except:
+    except TypeError:
         warn_msg = fmt
     logger.warning('GEOS_NOTICE: %s\n' % warn_msg)
 notice_h = NOTICEFUNC(notice_h)
@@ -75,7 +75,7 @@ def error_h(fmt, lst):
     fmt, lst = fmt.decode(), lst.decode()
     try:
         err_msg = fmt % lst
-    except:
+    except TypeError:
         err_msg = fmt
     logger.error('GEOS_ERROR: %s\n' % err_msg)
 error_h = ERRORFUNC(error_h)

django/contrib/gis/sitemaps/views.py

@@ -8,6 +8,7 @@ from django.core.paginator import EmptyPage, PageNotAnInteger
 from django.contrib.gis.db.models.fields import GeometryField
 from django.db import connections, DEFAULT_DB_ALIAS
 from django.db.models import get_model
+from django.db.models.fields import FieldDoesNotExist
 from django.utils import six
 from django.utils.translation import ugettext as _
 
@@ -77,10 +78,10 @@ def kml(request, label, model, field_name=None, compress=False, using=DEFAULT_DB
 
     if field_name:
         try:
-            info = klass._meta.get_field_by_name(field_name)
-            if not isinstance(info[0], GeometryField):
-                raise Exception
-        except:
+            field, _, _, _ = klass._meta.get_field_by_name(field_name)
+            if not isinstance(field, GeometryField):
+                raise FieldDoesNotExist
+        except FieldDoesNotExist:
             raise Http404('Invalid geometry field.')
 
     connection = connections[using]

django/contrib/gis/utils/__init__.py

@@ -7,11 +7,12 @@ if HAS_GDAL:
     from django.contrib.gis.utils.ogrinfo import ogrinfo, sample
     from django.contrib.gis.utils.ogrinspect import mapping, ogrinspect
     from django.contrib.gis.utils.srs import add_postgis_srs, add_srs_entry
+    from django.core.exceptions import ImproperlyConfigured
     try:
         # LayerMapping requires DJANGO_SETTINGS_MODULE to be set,
         # so this needs to be in try/except.
         from django.contrib.gis.utils.layermapping import LayerMapping, LayerMapError
-    except:
+    except ImproperlyConfigured:
         pass
 
 from django.contrib.gis.utils.wkt import precision_wkt

django/contrib/gis/utils/layermapping.py

@@ -7,7 +7,7 @@
    http://geodjango.org/docs/layermapping.html
 """
 import sys
-from decimal import Decimal
+from decimal import Decimal, InvalidOperation as DecimalInvalidOperation
 from django.core.exceptions import ObjectDoesNotExist
 from django.db import connections, router
 from django.contrib.gis.db.models import GeometryField
@@ -337,7 +337,7 @@ class LayerMapping(object):
             try:
                 # Creating an instance of the Decimal value to use.
                 d = Decimal(str(ogr_field.value))
-            except:
+            except DecimalInvalidOperation:
                 raise InvalidDecimal('Could not construct decimal from: %s' % ogr_field.value)
 
             # Getting the decimal value as a tuple.
@@ -365,7 +365,7 @@ class LayerMapping(object):
             # Attempt to convert any OFTReal and OFTString value to an OFTInteger.
             try:
                 val = int(ogr_field.value)
-            except:
+            except ValueError:
                 raise InvalidInteger('Could not construct integer from: %s' % ogr_field.value)
         else:
             val = ogr_field.value
@@ -547,8 +547,6 @@ class LayerMapping(object):
                         m.save(using=self.using)
                         num_saved += 1
                         if verbose: stream.write('%s: %s\n' % ('Updated' if is_update else 'Saved', m))
-                    except SystemExit:
-                        raise
                     except Exception as msg:
                         if strict:
                             # Bailing out if the `strict` keyword is set.
@@ -588,7 +586,7 @@ class LayerMapping(object):
                 try:
                     num_feat, num_saved = _save(step_slice, num_feat, num_saved)
                     beg = end
-                except:
+                except:  # Deliberately catch everything
                     stream.write('%s\nFailed to save slice: %s\n' % ('=-' * 20, step_slice))
                     raise
         else:

django/core/mail/backends/console.py

@@ -28,7 +28,7 @@ class EmailBackend(BaseEmailBackend):
                     msg_count += 1
                 if stream_created:
                     self.close()
-            except:
+            except Exception:
                 if not self.fail_silently:
                     raise
         return msg_count

django/core/mail/backends/smtp.py

@@ -56,7 +56,7 @@ class EmailBackend(BaseEmailBackend):
             if self.username and self.password:
                 self.connection.login(self.username, self.password)
             return True
-        except:
+        except smtplib.SMTPException:
             if not self.fail_silently:
                 raise
 
@@ -72,7 +72,7 @@ class EmailBackend(BaseEmailBackend):
                 # sometimes, or when the connection was already disconnected
                 # by the server.
                 self.connection.close()
-            except:
+            except smtplib.SMTPException:
                 if self.fail_silently:
                     return
                 raise
@@ -113,7 +113,7 @@ class EmailBackend(BaseEmailBackend):
         try:
             self.connection.sendmail(from_email, recipients,
                     force_bytes(message.as_string(), charset))
-        except:
+        except smtplib.SMTPException:
             if not self.fail_silently:
                 raise
             return False

django/core/management/__init__.py

@@ -209,7 +209,7 @@ class LaxOptionParser(OptionParser):
                     # dealing with options
                     del rargs[0]
                     raise Exception
-            except:
+            except:  # Needed because we might need to catch a SystemExit
                 largs.append(arg)
 
 class ManagementUtility(object):
@@ -360,7 +360,7 @@ class ManagementUtility(object):
         try:
             options, args = parser.parse_args(self.argv)
             handle_default_options(options)
-        except:
+        except:  # Needed because parser.parse_args can raise SystemExit
             pass # Ignore any option errors at this point.
 
         try:

django/core/management/sql.py

@@ -63,7 +63,7 @@ def sql_delete(app, style, connection):
     # This should work even if a connection isn't available
     try:
         cursor = connection.cursor()
-    except:
+    except Exception:
         cursor = None
 
     # Figure out which tables already exist

django/db/backends/oracle/base.py

@@ -620,7 +620,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
 
         try:
             self.connection.stmtcachesize = 20
-        except:
+        except AttributeError:
             # Django docs specify cx_Oracle version 4.3.1 or higher, but
             # stmtcachesize is available only in 4.3.2 and up.
             pass

django/http/multipartparser.py

@@ -7,6 +7,7 @@ file upload handlers for processing.
 from __future__ import unicode_literals
 
 import base64
+import binascii
 import cgi
 import sys
 
@@ -33,6 +34,8 @@ RAW = "raw"
 FILE = "file"
 FIELD = "field"
 
+_BASE64_DECODE_ERROR = TypeError if six.PY2 else binascii.Error
+
 class MultiPartParser(object):
     """
     A rfc2388 multipart/form-data parser.
@@ -161,8 +164,8 @@ class MultiPartParser(object):
                     if transfer_encoding == 'base64':
                         raw_data = field_stream.read()
                         try:
-                            data = str(raw_data).decode('base64')
-                        except:
+                            data = base64.b64decode(raw_data)
+                        except _BASE64_DECODE_ERROR:
                             data = raw_data
                     else:
                         data = field_stream.read()
@@ -546,7 +549,7 @@ def parse_boundary_stream(stream, max_header_size):
         main_value_pair, params = parse_header(line)
         try:
             name, value = main_value_pair.split(':', 1)
-        except:
+        except ValueError:
             raise ValueError("Invalid header: %r" % line)
         return name, (value, params)
 
@@ -571,7 +574,7 @@ def parse_boundary_stream(stream, max_header_size):
         # parameters") is from the Python docs.
         try:
             name, (value, params) = _parse_header(line)
-        except:
+        except ValueError:
             continue
 
         if name == 'content-disposition':

django/http/request.py

@@ -16,7 +16,7 @@ from django.conf import settings
 from django.core import signing
 from django.core.exceptions import DisallowedHost, ImproperlyConfigured
 from django.core.files import uploadhandler
-from django.http.multipartparser import MultiPartParser
+from django.http.multipartparser import MultiPartParser, MultiPartParserError
 from django.utils import six
 from django.utils.datastructures import MultiValueDict, ImmutableList
 from django.utils.encoding import force_bytes, force_text, force_str, iri_to_uri
@@ -222,7 +222,7 @@ class HttpRequest(object):
                 data = self
             try:
                 self._post, self._files = self.parse_file_upload(self.META, data)
-            except:
+            except MultiPartParserError:
                 # An error occured while parsing POST data. Since when
                 # formatting the error the request handler might access
                 # self.POST, set self._post and self._file to prevent
@@ -230,7 +230,7 @@ class HttpRequest(object):
                 # Mark that an error occured. This allows self.__repr__ to
                 # be explicit about it instead of simply representing an
                 # empty POST
-                self._mark_post_parse_error()
+                # self._mark_post_parse_error()
                 raise
         elif self.META.get('CONTENT_TYPE', '').startswith('application/x-www-form-urlencoded'):
             self._post, self._files = QueryDict(self.body, encoding=self._encoding), MultiValueDict()

django/template/loader_tags.py

@@ -143,7 +143,7 @@ class IncludeNode(Node):
                 return template.render(context.new(values))
             with context.push(**values):
                 return template.render(context)
-        except:
+        except Exception:
             if settings.TEMPLATE_DEBUG:
                 raise
             return ''