import inspect from optparse import make_option from django.contrib.gis import gdal from django.core.management.base import LabelCommand, CommandError def layer_option(option, opt, value, parser): """ Callback for `make_option` for the `ogrinspect` `layer_key` keyword option which may be an integer or a string. """ try: dest = int(value) except ValueError: dest = value setattr(parser.values, option.dest, dest) def list_option(option, opt, value, parser): """ Callback for `make_option` for `ogrinspect` keywords that require a string list. If the string is 'True'/'true' then the option value will be a boolean instead. """ if value.lower() == 'true': dest = True else: dest = [s for s in value.split(',')] setattr(parser.values, option.dest, dest) class Command(LabelCommand): help = ('Inspects the given OGR-compatible data source (e.g., a shapefile) and outputs\n' 'a GeoDjango model with the given model name. For example:\n' ' ./manage.py ogrinspect zipcode.shp Zipcode') args = '[data_source] [model_name]' option_list = LabelCommand.option_list + ( make_option('--blank', dest='blank', type='string', action='callback', callback=list_option, default=False, help='Use a comma separated list of OGR field names to add ' 'the `blank=True` option to the field definition. Set with' '`true` to apply to all applicable fields.'), make_option('--decimal', dest='decimal', type='string', action='callback', callback=list_option, default=False, help='Use a comma separated list of OGR float fields to ' 'generate `DecimalField` instead of the default ' '`FloatField`. Set to `true` to apply to all OGR float fields.'), make_option('--geom-name', dest='geom_name', type='string', default='geom', help='Specifies the model name for the Geometry Field ' '(defaults to `geom`)'), make_option('--layer', dest='layer_key', type='string', action='callback', callback=layer_option, default=0, help='The key for specifying which layer in the OGR data ' 'source to use. Defaults to 0 (the first layer). May be ' 'an integer or a string identifier for the layer.'), make_option('--multi-geom', action='store_true', dest='multi_geom', default=False, help='Treat the geometry in the data source as a geometry collection.'), make_option('--name-field', dest='name_field', help='Specifies a field name to return for the `__unicode__`/`__str__` function.'), make_option('--no-imports', action='store_false', dest='imports', default=True, help='Do not include `from django.contrib.gis.db import models` ' 'statement.'), make_option('--null', dest='null', type='string', action='callback', callback=list_option, default=False, help='Use a comma separated list of OGR field names to add ' 'the `null=True` option to the field definition. Set with' '`true` to apply to all applicable fields.'), make_option('--srid', dest='srid', help='The SRID to use for the Geometry Field. If it can be ' 'determined, the SRID of the data source is used.'), make_option('--mapping', action='store_true', dest='mapping', help='Generate mapping dictionary for use with `LayerMapping`.') ) requires_system_checks = False def handle(self, *args, **options): try: data_source, model_name = args except ValueError: raise CommandError('Invalid arguments, must provide: %s' % self.args) if not gdal.HAS_GDAL: raise CommandError('GDAL is required to inspect geospatial data sources.') # Getting the OGR DataSource from the string parameter. try: ds = gdal.DataSource(data_source) except gdal.OGRException as msg: raise CommandError(msg) # Returning the output of ogrinspect with the given arguments # and options. from django.contrib.gis.utils.ogrinspect import _ogrinspect, mapping # Filter options to params accepted by `_ogrinspect` ogr_options = dict((k, v) for k, v in options.items() if k in inspect.getargspec(_ogrinspect).args and v is not None) output = [s for s in _ogrinspect(ds, model_name, **ogr_options)] if options['mapping']: # Constructing the keyword arguments for `mapping`, and # calling it on the data source. kwargs = {'geom_name': options['geom_name'], 'layer_key': options['layer_key'], 'multi_geom': options['multi_geom'], } mapping_dict = mapping(ds, **kwargs) # This extra legwork is so that the dictionary definition comes # out in the same order as the fields in the model definition. rev_mapping = dict((v, k) for k, v in mapping_dict.items()) output.extend(['', '# Auto-generated `LayerMapping` dictionary for %s model' % model_name, '%s_mapping = {' % model_name.lower()]) output.extend(" '%s' : '%s'," % (rev_mapping[ogr_fld], ogr_fld) for ogr_fld in ds[options['layer_key']].fields) output.extend(" '%s' : '%s'," % (options['geom_name'], mapping_dict[options['geom_name']]), '}') return '\n'.join(output) + '\n'