1 from django.core.management.base import NoArgsCommand, CommandError

     2 

     3 class Command(NoArgsCommand):

     4     help = "Introspects the database tables in the given database and outputs a Django model module."

     5 

     6     requires_model_validation = False

     7 

     8     def handle_noargs(self, **options):

     9         try:

    10             for line in self.handle_inspection():

    11                 print line

    12         except NotImplementedError:

    13             raise CommandError("Database inspection isn't supported for the currently selected database backend.")

    14 

    15     def handle_inspection(self):

    16         from django.db import connection, get_introspection_module

    17         import keyword

    18 

    19         introspection_module = get_introspection_module()

    20 

    21         table2model = lambda table_name: table_name.title().replace('_', '')

    22 

    23         cursor = connection.cursor()

    24         yield "# This is an auto-generated Django model module."

    25         yield "# You'll have to do the following manually to clean this up:"

    26         yield "#     * Rearrange models' order"

    27         yield "#     * Make sure each model has one field with primary_key=True"

    28         yield "# Feel free to rename the models, but don't rename db_table values or field names."

    29         yield "#"

    30         yield "# Also note: You'll have to insert the output of 'django-admin.py sqlcustom [appname]'"

    31         yield "# into your database."

    32         yield ''

    33         yield 'from django.db import models'

    34         yield ''

    35         for table_name in introspection_module.get_table_list(cursor):

    36             yield 'class %s(models.Model):' % table2model(table_name)

    37             try:

    38                 relations = introspection_module.get_relations(cursor, table_name)

    39             except NotImplementedError:

    40                 relations = {}

    41             try:

    42                 indexes = introspection_module.get_indexes(cursor, table_name)

    43             except NotImplementedError:

    44                 indexes = {}

    45             for i, row in enumerate(introspection_module.get_table_description(cursor, table_name)):

    46                 att_name = row[0].lower()

    47                 comment_notes = [] # Holds Field notes, to be displayed in a Python comment.

    48                 extra_params = {}  # Holds Field parameters such as 'db_column'.

    49 

    50                 if ' ' in att_name:

    51                     extra_params['db_column'] = att_name

    52                     att_name = att_name.replace(' ', '')

    53                     comment_notes.append('Field renamed to remove spaces.')

    54                 if keyword.iskeyword(att_name):

    55                     extra_params['db_column'] = att_name

    56                     att_name += '_field'

    57                     comment_notes.append('Field renamed because it was a Python reserved word.')

    58 

    59                 if i in relations:

    60                     rel_to = relations[i][1] == table_name and "'self'" or table2model(relations[i][1])

    61                     field_type = 'ForeignKey(%s' % rel_to

    62                     if att_name.endswith('_id'):

    63                         att_name = att_name[:-3]

    64                     else:

    65                         extra_params['db_column'] = att_name

    66                 else:

    67                     try:

    68                         field_type = introspection_module.DATA_TYPES_REVERSE[row[1]]

    69                     except KeyError:

    70                         field_type = 'TextField'

    71                         comment_notes.append('This field type is a guess.')

    72 

    73                     # This is a hook for DATA_TYPES_REVERSE to return a tuple of

    74                     # (field_type, extra_params_dict).

    75                     if type(field_type) is tuple:

    76                         field_type, new_params = field_type

    77                         extra_params.update(new_params)

    78 

    79                     # Add max_length for all CharFields.

    80                     if field_type == 'CharField' and row[3]:

    81                         extra_params['max_length'] = row[3]

    82 

    83                     if field_type == 'DecimalField':

    84                         extra_params['max_digits'] = row[4]

    85                         extra_params['decimal_places'] = row[5]

    86 

    87                     # Add primary_key and unique, if necessary.

    88                     column_name = extra_params.get('db_column', att_name)

    89                     if column_name in indexes:

    90                         if indexes[column_name]['primary_key']:

    91                             extra_params['primary_key'] = True

    92                         elif indexes[column_name]['unique']:

    93                             extra_params['unique'] = True

    94 

    95                     field_type += '('

    96 

    97                 # Don't output 'id = meta.AutoField(primary_key=True)', because

    98                 # that's assumed if it doesn't exist.

    99                 if att_name == 'id' and field_type == 'AutoField(' and extra_params == {'primary_key': True}:

   100                     continue

   101 

   102                 # Add 'null' and 'blank', if the 'null_ok' flag was present in the

   103                 # table description.

   104                 if row[6]: # If it's NULL...

   105                     extra_params['blank'] = True

   106                     if not field_type in ('TextField(', 'CharField('):

   107                         extra_params['null'] = True

   108 

   109                 field_desc = '%s = models.%s' % (att_name, field_type)

   110                 if extra_params:

   111                     if not field_desc.endswith('('):

   112                         field_desc += ', '

   113                     field_desc += ', '.join(['%s=%r' % (k, v) for k, v in extra_params.items()])

   114                 field_desc += ')'

   115                 if comment_notes:

   116                     field_desc += ' # ' + ' '.join(comment_notes)

   117                 yield '    %s' % field_desc

   118             yield '    class Meta:'

   119             yield '        db_table = %r' % table_name

   120             yield ''