gis: Went through and cleaned up ogrinspect code and added features…

… provided in patch from springmeyer (thanks); `add_postgis_srs` requires GDAL, so modified `utils` imports accordingly.

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@7570 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/utils/__init__.py

@@ -6,6 +6,7 @@
 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
     try:
         # LayerMapping requires DJANGO_SETTINGS_MODULE to be set, 
         # so this needs to be in try/except.
@@ -20,6 +21,5 @@
 except:
     HAS_GEOIP = False
 
-from django.contrib.gis.utils.srs import add_postgis_srs
 from django.contrib.gis.utils.wkt import precision_wkt
 

django/contrib/gis/utils/ogrinspect.py

@@ -1,13 +1,14 @@
 """
- This module is for inspecting OGR data sources and generating either
- models for GeoDjango and/or mapping dictionaries for use with the
- LayerMapping utility.
+This module is for inspecting OGR data sources and generating either
+models for GeoDjango and/or mapping dictionaries for use with the
+`LayerMapping` utility.
 
- Author: Travis Pinney
+Author: Travis Pinney, Dane Springmeyer, & Justin Bronn
 """
-
+from itertools import izip
 # Requires GDAL to use.
 from django.contrib.gis.gdal import DataSource
+from django.contrib.gis.gdal.field import OFTDate, OFTDateTime, OFTInteger, OFTReal, OFTString, OFTTime
 
 def mapping(data_source, geom_name='geom', layer_key=0):
     """
@@ -16,7 +17,7 @@ def mapping(data_source, geom_name='geom', layer_key=0):
 
     Keyword Arguments:
      `geom_name` => The name of the geometry field to use for the model.
-
+     
      `layer_key` => The key for specifying which layer in the DataSource to use;
        defaults to 0 (the first layer).  May be an integer index or a string
        identifier for the layer.
@@ -47,26 +48,78 @@ def ogrinspect(*args, **kwargs):
     Given a data source (either a string or a DataSource object) and a string
     model name this function will generate a GeoDjango model.
 
-    Keyword Arguments
-     `geom_name` => For specifying the model name for the Geometry Field.
+    Usage:
+    
+    >>> from django.contrib.gis.utils import ogrinspect
+    >>> ogrinspect('/path/to/shapefile.shp','NewModel')
+    
+    ...will print model definition to stout
+    
+    or put this in a python script and use to redirect the output to a new
+    model like:
+    
+    $ python generate_model.py > myapp/models.py
+    
+    # generate_model.py 
+    from django.contrib.gis.utils import ogrinspect
+    shp_file = 'data/mapping_hacks/world_borders.shp'
+    model_name = 'WorldBorders'
+
+    print ogrinspect(shp_file, model_name, multi_geom=True, srid=4326,
+                     geom_name='shapes', blank=True)
+                     
+    Required Arguments
+     `datasource` => string or DataSource object to file pointer
+     
+     `model name` => string of name of new model class to create
+      
+    Optional Keyword Arguments
+     `geom_name` => For specifying the model name for the Geometry Field. 
+       Otherwise will default to `geom`
 
      `layer_key` => The key for specifying which layer in the DataSource to use;
        defaults to 0 (the first layer).  May be an integer index or a string
        identifier for the layer.
 
      `srid` => The SRID to use for the Geometry Field.  If it can be determined,
-       the SRID of the datasource
-
+       the SRID of the datasource is used.
+      
+     `multi_geom` => Boolean (default: False) - specify as multigeometry.
+     
+     `name_field` => String - specifies a field name to return for the
+       `__unicode__` function (which will be generated if specified).
+     
+     `imports` => Boolean (default: True) - set to False to omit the 
+       `from django.contrib.gis.db import models` code from the 
+       autogenerated models thus avoiding duplicated imports when building
+       more than one model by batching ogrinspect()
+     
+     `decimal` => Boolean or sequence (default: False).  When set to True
+       all generated model fields corresponding to the `OFTReal` type will
+       be `DecimalField` instead of `FloatField`.  A sequence of specific
+       field names to generate as `DecimalField` may also be used.
+
+     `blank` => Boolean or sequence (default: False).  When set to True all
+       generated model fields will have `blank=True`.  If the user wants to 
+       give specific fields to have blank, then a list/tuple of OGR field
+       names may be used.
+
+     `null` => Boolean (default: False) - When set to True all generated
+       model fields will have `null=True`.  If the user wants to specify
+       give specific fields to have null, then a list/tuple of OGR field
+       names may be used.
+     
     Note: This routine calls the _ogrinspect() helper to do the heavy lifting.
     """
     return '\n'.join(s for s in _ogrinspect(*args, **kwargs))
 
-def _ogrinspect(data_source, model_name, geom_name='geom', layer_key=0, srid=None):
+def _ogrinspect(data_source, model_name, geom_name='geom', layer_key=0, srid=None,
+                multi_geom=False, name_field=None, imports=True, 
+                decimal=False, blank=False, null=False):
     """
     Helper routine for `ogrinspect` that generates GeoDjango models corresponding
     to the given data source.  See the `ogrinspect` docstring for more details.
     """
-
     # Getting the DataSource
     if isinstance(data_source, str):
         data_source = DataSource(data_source)
@@ -75,40 +128,77 @@ def _ogrinspect(data_source, model_name, geom_name='geom', layer_key=0, srid=Non
     else:
         raise TypeError('Data source parameter must be a string or a DataSource object.')
 
-    yield '# This is an auto-generated Django model module created by ogrinspect.'
-    yield 'from django.contrib.gis.db import models'
-    yield ''
+    # Getting the layer corresponding to the layer key and getting
+    # a string listing of all OGR fields in the Layer.
+    layer = data_source[layer_key]
+    ogr_fields = layer.fields
+
+    # Creating lists from the `null`, `blank`, and `decimal`
+    # keyword arguments.
+    def process_kwarg(kwarg):
+        if isinstance(kwarg, (list, tuple)):
+            return [s.lower() for s in kwarg] 
+        elif kwarg:
+            return [s.lower() for s in ogr_fields]
+        else:
+            return []
+    null_fields = process_kwarg(null)
+    blank_fields = process_kwarg(blank)
+    decimal_fields = process_kwarg(decimal)
+
+    # Gets the `null` and `blank` keywords for the given field name.
+    def get_kwargs_str(field_name):
+        kwlist = []
+        if field_name.lower() in null_fields: kwlist.append('null=True')
+        if field_name.lower() in blank_fields: kwlist.append('blank=True')
+        if kwlist: return ', ' + ', '.join(kwlist)
+        else: return ''
+
+    # For those wishing to disable the imports.
+    if imports:
+        yield '# This is an auto-generated Django model module created by ogrinspect.'
+        yield 'from django.contrib.gis.db import models'
+        yield ''
+
     yield 'class %s(models.Model):' % model_name
 
-    layer = data_source[layer_key]        
-
-    for width, precision, field in zip(layer.field_widths, layer.field_precisions, layer.fields):
-        feature = layer[0]
-        fld_type = feature[field].type_name
-        mfield = field.lower()
-
-        if mfield[-1:] == '_':
-            mfield += 'field'
+    for field_name, width, precision, field_type in izip(ogr_fields, layer.field_widths, layer.field_precisions, layer.field_types):
+        # The model field name.
+        mfield = field_name.lower()
+        if mfield[-1:] == '_': mfield += 'field'
 
-        if fld_type == 'Real':
-            yield '    %s = models.DecimalField(max_digits=%s, decimal_places=%s)' % (mfield, width, precision)
-        elif fld_type == 'Integer':
-            yield '    %s = models.IntegerField()' % mfield
-        elif fld_type == 'String':
-            yield '    %s = models.CharField(max_length=%s)' % (mfield, width)
-        elif fld_type == 'Date':
-            yield '    %s = models.DateField()' % mfield
-        elif fld_type == 'DateTime':
-            yield '    %s = models.DateTimeField()' % mfield
-        elif fld_type == 'Time':
-            yield '    %s = models.TimeField()' % mfield
+        # Getting the keyword args string.
+        kwargs_str = get_kwargs_str(field_name)
+
+        if field_type is OFTReal:
+            # By default OFTReals are mapped to `FloatField`, however, they
+            # may also be mapped to `DecimalField` if specified in the 
+            # `decimal` keyword.
+            if field_name.lower() in decimal_fields:
+                yield '    %s = models.DecimalField(max_digits=%d, decimal_places=%d%s)' % (mfield, width, precision, kwargs_str)
+            else:
+                yield '    %s = models.FloatField(%s)' % (mfield, kwargs_str[2:])
+        elif field_type is OFTInteger:
+            yield '    %s = models.IntegerField(%s)' % (mfield, kwargs_str[2:])
+        elif field_type is OFTString:
+            yield '    %s = models.CharField(max_length=%s%s)' % (mfield, width, kwargs_str)
+        elif field_type is OFTDate:
+            yield '    %s = models.DateField(%s)' % (mfield, kwargs_str[2:])
+        elif field_type is OFTDateTime:
+            yield '    %s = models.DateTimeField(%s)' % (mfield, kwargs_str[2:])
+        elif field_type is OFTDate:
+            yield '    %s = models.TimeField(%s)' % (mfield, kwargs_str[2:])
         else:
-            raise Exception('Unknown field type %s in %s' % (fld_type, mfield))
+            raise TypeError('Unknown field type %s in %s' % (fld_type, mfield))
 
-    # Getting the geometry type
+    # TODO: Autodetection of multigeometry types (see #7218).
     gtype = layer.geom_type
-
-    # Setting up the SRID parameter string.
+    if multi_geom and gtype.num in (1, 2, 3):
+        geom_field = 'Multi%s' % gtype.django
+    else:
+        geom_field = gtype.django
+
+    # Setting up the SRID keyword string.
     if srid is None:
         if layer.srs is None:
             srid_str = 'srid=-1'
@@ -117,12 +207,16 @@ def _ogrinspect(data_source, model_name, geom_name='geom', layer_key=0, srid=Non
             if srid is None:
                 srid_str = 'srid=-1'
             elif srid == 4326:
-                # WGS84 is the default.
+                # WGS84 is already the default.
                 srid_str = ''
             else:
                 srid_str = 'srid=%s' % srid
     else:
         srid_str = 'srid=%s' % srid
 
-    yield '    %s = models.%s(%s)' % (geom_name, gtype.django, srid_str)
+    yield '    %s = models.%s(%s)' % (geom_name, geom_field, srid_str)
     yield '    objects = models.GeoManager()'
+
+    if name_field:
+        yield ''
+        yield '    def __unicode__(self): return self.%s' % name_field

django/contrib/gis/utils/srs.py

@@ -1,5 +1,3 @@
-from django.contrib.gis.gdal import SpatialReference
-
 def add_postgis_srs(srs):
     """
     This function takes a GDAL SpatialReference system and adds its
@@ -15,6 +13,7 @@ def add_postgis_srs(srs):
     probably be changed.
     """
     from django.contrib.gis.models import SpatialRefSys
+    from django.contrib.gis.gdal import SpatialReference
 
     if not isinstance(srs, SpatialReference):
         srs = SpatialReference(srs)