web/lib/django_extensions/management/commands/syncdata.py
changeset 3 526ebd3988b0
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1:ebaad720f88b 3:526ebd3988b0
       
     1 """ 
       
     2 SyncData
       
     3 ========
       
     4 
       
     5 Django command similar to 'loaddata' but also deletes.
       
     6 After 'syncdata' has run, the database will have the same data as the fixture - anything
       
     7 missing will of been added, anything different will of been updated,
       
     8 and anything extra will of been deleted.
       
     9 """
       
    10 
       
    11 from django.core.management.base import BaseCommand
       
    12 from django.core.management.color import no_style
       
    13 from optparse import make_option
       
    14 import sys
       
    15 import os
       
    16 
       
    17 class Command(BaseCommand):
       
    18     """ syncdata command """
       
    19     
       
    20     help = 'Makes the current database have the same data as the fixture(s), no more, no less.'
       
    21     args = "fixture [fixture ...]"
       
    22     
       
    23     def remove_objects_not_in(self, objects_to_keep, verbosity):
       
    24         """
       
    25         Deletes all the objects in the database that are not in objects_to_keep.
       
    26         - objects_to_keep: A map where the keys are classes, and the values are a
       
    27          set of the objects of that class we should keep.
       
    28         """
       
    29         for class_ in objects_to_keep.keys():
       
    30 
       
    31             current = class_.objects.all()
       
    32             current_ids = set( [x.id for x in current] )
       
    33             keep_ids = set( [x.id for x in objects_to_keep[class_]] )
       
    34 
       
    35             remove_these_ones = current_ids.difference(keep_ids)
       
    36             if remove_these_ones:
       
    37 
       
    38                 for obj in current:
       
    39                     if obj.id in remove_these_ones:
       
    40                         obj.delete()
       
    41                         if verbosity >= 2:
       
    42                             print "Deleted object: "+ unicode(obj)
       
    43 
       
    44             if verbosity > 0 and remove_these_ones:
       
    45                 num_deleted = len(remove_these_ones)
       
    46                 if num_deleted > 1:
       
    47                     type_deleted = unicode(class_._meta.verbose_name_plural)
       
    48                 else:
       
    49                     type_deleted = unicode(class_._meta.verbose_name)
       
    50 
       
    51                 print "Deleted "+ str(num_deleted) +" "+ type_deleted
       
    52 
       
    53     def handle(self, *fixture_labels, **options):
       
    54         """ Main method of a Django command """
       
    55         from django.db.models import get_apps
       
    56         from django.core import serializers
       
    57         from django.db import connection, transaction
       
    58         from django.conf import settings
       
    59 
       
    60         self.style = no_style()
       
    61 
       
    62         verbosity = int(options.get('verbosity', 1))
       
    63         show_traceback = options.get('traceback', False)
       
    64         
       
    65         # Keep a count of the installed objects and fixtures
       
    66         fixture_count = 0
       
    67         object_count = 0
       
    68         objects_per_fixture = []
       
    69         models = set()
       
    70 
       
    71         humanize = lambda dirname: dirname and "'%s'" % dirname or 'absolute path'
       
    72 
       
    73         # Get a cursor (even though we don't need one yet). This has
       
    74         # the side effect of initializing the test database (if
       
    75         # it isn't already initialized).
       
    76         cursor = connection.cursor()
       
    77 
       
    78         # Start transaction management. All fixtures are installed in a
       
    79         # single transaction to ensure that all references are resolved.
       
    80         transaction.commit_unless_managed()
       
    81         transaction.enter_transaction_management()
       
    82         transaction.managed(True)
       
    83 
       
    84         app_fixtures = [os.path.join(os.path.dirname(app.__file__), 'fixtures') \
       
    85                         for app in get_apps()]
       
    86         for fixture_label in fixture_labels:
       
    87             parts = fixture_label.split('.')
       
    88             if len(parts) == 1:
       
    89                 fixture_name = fixture_label
       
    90                 formats = serializers.get_public_serializer_formats()
       
    91             else:
       
    92                 fixture_name, format = '.'.join(parts[:-1]), parts[-1]
       
    93                 if format in serializers.get_public_serializer_formats():
       
    94                     formats = [format]
       
    95                 else:
       
    96                     formats = []
       
    97 
       
    98             if formats:
       
    99                 if verbosity > 1:
       
   100                     print "Loading '%s' fixtures..." % fixture_name
       
   101             else:
       
   102                 sys.stderr.write(
       
   103                     self.style.ERROR("Problem installing fixture '%s': %s is not a known "+ \
       
   104                                      "serialization format." % (fixture_name, format))
       
   105                     )
       
   106                 transaction.rollback()
       
   107                 transaction.leave_transaction_management()
       
   108                 return
       
   109 
       
   110             if os.path.isabs(fixture_name):
       
   111                 fixture_dirs = [fixture_name]
       
   112             else:
       
   113                 fixture_dirs = app_fixtures + list(settings.FIXTURE_DIRS) + ['']
       
   114 
       
   115             for fixture_dir in fixture_dirs:
       
   116                 if verbosity > 1:
       
   117                     print "Checking %s for fixtures..." % humanize(fixture_dir)
       
   118 
       
   119                 label_found = False
       
   120                 for format in formats:
       
   121                     serializer = serializers.get_serializer(format)
       
   122                     if verbosity > 1:
       
   123                         print "Trying %s for %s fixture '%s'..." % \
       
   124                             (humanize(fixture_dir), format, fixture_name)
       
   125                     try:
       
   126                         full_path = os.path.join(fixture_dir, '.'.join([fixture_name, format]))
       
   127                         fixture = open(full_path, 'r')
       
   128                         if label_found:
       
   129                             fixture.close()
       
   130                             print self.style.ERROR("Multiple fixtures named '%s' in %s. Aborting." %
       
   131                                 (fixture_name, humanize(fixture_dir)))
       
   132                             transaction.rollback()
       
   133                             transaction.leave_transaction_management()
       
   134                             return
       
   135                         else:
       
   136                             fixture_count += 1
       
   137                             objects_per_fixture.append(0)
       
   138                             if verbosity > 0:
       
   139                                 print "Installing %s fixture '%s' from %s." % \
       
   140                                     (format, fixture_name, humanize(fixture_dir))
       
   141                             try:
       
   142                                 objects_to_keep = {}
       
   143                                 objects = serializers.deserialize(format, fixture)
       
   144                                 for obj in objects:
       
   145                                     object_count += 1
       
   146                                     objects_per_fixture[-1] += 1
       
   147 
       
   148                                     class_ = obj.object.__class__
       
   149                                     if not class_ in objects_to_keep:
       
   150                                         objects_to_keep[class_] = set()
       
   151                                     objects_to_keep[class_].add(obj.object)
       
   152                                     
       
   153                                     models.add(class_)
       
   154                                     obj.save()
       
   155 
       
   156                                 self.remove_objects_not_in(objects_to_keep, verbosity)
       
   157 
       
   158                                 label_found = True
       
   159                             except (SystemExit, KeyboardInterrupt):
       
   160                                 raise
       
   161                             except Exception:
       
   162                                 import traceback
       
   163                                 fixture.close()
       
   164                                 transaction.rollback()
       
   165                                 transaction.leave_transaction_management()
       
   166                                 if show_traceback:
       
   167                                     traceback.print_exc()
       
   168                                 else:
       
   169                                     sys.stderr.write(
       
   170                                         self.style.ERROR("Problem installing fixture '%s': %s\n" %
       
   171                                              (full_path, traceback.format_exc())))
       
   172                                 return
       
   173                             fixture.close()
       
   174                     except:
       
   175                         if verbosity > 1:
       
   176                             print "No %s fixture '%s' in %s." % \
       
   177                                 (format, fixture_name, humanize(fixture_dir))
       
   178 
       
   179         # If any of the fixtures we loaded contain 0 objects, assume that an 
       
   180         # error was encountered during fixture loading.
       
   181         if 0 in objects_per_fixture:
       
   182             sys.stderr.write(
       
   183                 self.style.ERROR("No fixture data found for '%s'. (File format may be invalid.)" %
       
   184                     (fixture_name)))
       
   185             transaction.rollback()
       
   186             transaction.leave_transaction_management()
       
   187             return
       
   188             
       
   189         # If we found even one object in a fixture, we need to reset the 
       
   190         # database sequences.
       
   191         if object_count > 0:
       
   192             sequence_sql = connection.ops.sequence_reset_sql(self.style, models)
       
   193             if sequence_sql:
       
   194                 if verbosity > 1:
       
   195                     print "Resetting sequences"
       
   196                 for line in sequence_sql:
       
   197                     cursor.execute(line)
       
   198             
       
   199         transaction.commit()
       
   200         transaction.leave_transaction_management()
       
   201 
       
   202         if object_count == 0:
       
   203             if verbosity > 1:
       
   204                 print "No fixtures found."
       
   205         else:
       
   206             if verbosity > 0:
       
   207                 print "Installed %d object(s) from %d fixture(s)" % (object_count, fixture_count)
       
   208                 
       
   209         # Close the DB connection. This is required as a workaround for an
       
   210         # edge case in MySQL: if the same connection is used to
       
   211         # create tables, load data, and query, the query can return
       
   212         # incorrect results. See Django #7572, MySQL #37735.
       
   213         connection.close()
       
   214 
       
   215 # Backwards compatibility for Django r9110
       
   216 if not [opt for opt in Command.option_list if opt.dest=='verbosity']:
       
   217     Command.option_list += (
       
   218         make_option('--verbosity', '-v', action="store", dest="verbosity",
       
   219             default='1', type='choice', choices=['0', '1', '2'],
       
   220             help="Verbosity level; 0=minimal output, 1=normal output, 2=all output"),
       
   221     )