rename-tables-for-django.py (needed for updates to django-cms 3.0)

rename-tables-for-django.py

=> ./manage.py datamigration your_app rename_plugin_tables


def rename_tables(db, table_mapping, reverse=False):
    """
    renames tables from source to destination name, if the source exists and the destination does
    not exist yet.
    """
    from django.db import connection
    if reverse:
        table_mapping = [(dst, src) for src, dst in table_mapping]
    table_names = connection.introspection.table_names()
    for source, destination in table_mapping:
        if source in table_names and destination in table_names:
            print u"    WARNING: not renaming {0} to {1}, because both tables already exist.".format(source, destination)
        elif source in table_names and destination not in table_names:
            print u"     - renaming {0} to {1}".format(source, destination)
            db.rename_table(source, destination)


def rename_tables_old_to_new(db, table_mapping):
    return rename_tables(db, table_mapping, reverse=False)


def rename_tables_new_to_old(db, table_mapping):
    return rename_tables(db, table_mapping, reverse=True)
    
    
class Migration(DataMigration):
    cms_plugin_table_mapping = (
        # (old_name, new_name),
        ('cmsplugin_whateverplugin', 'my_app_whateverplugin'),
    )

    def forwards(self, orm):
        rename_tables_old_to_new(db, self.cms_plugin_table_mapping)
        # ...
        
    def forwards_cmsplugins_automagically(self, orm):
        """
        does it all automagically. take care!
        """
        from cms.plugin_pool import plugin_pool
        mapping = []
        for plugin in plugin_pool.get_all_plugins():
            if plugin.model._meta.db_table.startswith('cmsplugin_'):
                old = plugin.model._meta.db_table
                # warning, no good if your plugin has "cmsplugin" in its tablename on itself...
                new = plugin.model._meta.db_table.replace(
                    'cmsplugin',
                    plugin.model._meta.app_label,
                )
                mapping.append((old, new))
        print mapping
        print "paste this mapping above in the code, to go back again!"
        rename_tables_old_to_new(db, mapping)

    def backwards(self, orm):
        rename_tables_new_to_old(db, self.cms_plugin_table_mapping)
        
    def backwards_automagic_to_be_done(self, orm):
        rename_tables_new_to_old(db, self.cms_plugin_table_mapping)