예제 #1
0
    def testExportFeatureRelations(self):
        """ Test exporting a feature with relations """

        #parent layer
        parent = QgsVectorLayer(
            "Point?field=fldtxt:string&field=fldint:integer&field=foreignkey:integer",
            "parent", "memory")
        pr = parent.dataProvider()
        pf1 = QgsFeature()
        pf1.setFields(parent.fields())
        pf1.setAttributes(["test1", 67, 123])
        pf2 = QgsFeature()
        pf2.setFields(parent.fields())
        pf2.setAttributes(["test2", 68, 124])
        assert pr.addFeatures([pf1, pf2])

        #child layer
        child = QgsVectorLayer(
            "Point?field=x:string&field=y:integer&field=z:integer",
            "referencedlayer", "memory")
        pr = child.dataProvider()
        f1 = QgsFeature()
        f1.setFields(child.fields())
        f1.setAttributes(["foo", 123, 321])
        f2 = QgsFeature()
        f2.setFields(child.fields())
        f2.setAttributes(["bar", 123, 654])
        f3 = QgsFeature()
        f3.setFields(child.fields())
        f3.setAttributes(["foobar", 124, 554])
        assert pr.addFeatures([f1, f2, f3])

        QgsProject.instance().addMapLayers([child, parent])

        rel = QgsRelation()
        rel.setId('rel1')
        rel.setName('relation one')
        rel.setReferencingLayer(child.id())
        rel.setReferencedLayer(parent.id())
        rel.addFieldPair('y', 'foreignkey')

        QgsProject.instance().relationManager().addRelation(rel)

        exporter = QgsJsonExporter()

        exporter.setVectorLayer(parent)
        self.assertEqual(exporter.vectorLayer(), parent)
        exporter.setIncludeRelated(True)
        self.assertEqual(exporter.includeRelated(), True)

        expected = """{
   "type":"Feature",
   "id":0,
   "geometry":null,
   "properties":{
      "fldtxt":"test1",
      "fldint":67,
      "foreignkey":123,
      "relation one":[{"x":"foo",
"y":123,
"z":321},
{"x":"bar",
"y":123,
"z":654}]
   }
}"""
        self.assertEqual(exporter.exportFeature(pf1), expected)

        expected = """{
   "type":"Feature",
   "id":0,
   "geometry":null,
   "properties":{
      "fldtxt":"test2",
      "fldint":68,
      "foreignkey":124,
      "relation one":[{"x":"foobar",
"y":124,
"z":554}]
   }
}"""
        self.assertEqual(exporter.exportFeature(pf2), expected)

        # with field formatter
        setup = QgsEditorWidgetSetup('ValueMap',
                                     {"map": {
                                         "apples": 123,
                                         "bananas": 124
                                     }})
        child.setEditorWidgetSetup(1, setup)
        expected = """{
   "type":"Feature",
   "id":0,
   "geometry":null,
   "properties":{
      "fldtxt":"test1",
      "fldint":67,
      "foreignkey":123,
      "relation one":[{"x":"foo",
"y":"apples",
"z":321},
{"x":"bar",
"y":"apples",
"z":654}]
   }
}"""
        self.assertEqual(exporter.exportFeature(pf1), expected)

        # test excluding related attributes
        exporter.setIncludeRelated(False)
        self.assertEqual(exporter.includeRelated(), False)

        expected = """{
   "type":"Feature",
   "id":0,
   "geometry":null,
   "properties":{
      "fldtxt":"test2",
      "fldint":68,
      "foreignkey":124
   }
}"""
        self.assertEqual(exporter.exportFeature(pf2), expected)

        # test without vector layer set
        exporter.setIncludeRelated(True)
        exporter.setVectorLayer(None)

        expected = """{
   "type":"Feature",
   "id":0,
   "geometry":null,
   "properties":{
      "fldtxt":"test2",
      "fldint":68,
      "foreignkey":124
   }
}"""
        self.assertEqual(exporter.exportFeature(pf2), expected)
예제 #2
0
    def testExportFeatures(self):
        """ Test exporting feature collections """

        fields = QgsFields()
        fields.append(QgsField("name", QVariant.String))
        fields.append(QgsField("cost", QVariant.Double))
        fields.append(QgsField("population", QVariant.Int))

        feature = QgsFeature(fields, 5)
        feature.setGeometry(QgsGeometry(QgsPoint(5, 6)))
        feature.setAttributes(['Valsier Peninsula', 6.8, 198])

        exporter = QgsJsonExporter()

        # single feature
        expected = """{ "type": "FeatureCollection",
    "features":[
{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}
]}"""
        self.assertEqual(exporter.exportFeatures([feature]), expected)

        # multiple features
        feature2 = QgsFeature(fields, 6)
        feature2.setGeometry(QgsGeometry(QgsPoint(7, 8)))
        feature2.setAttributes(['Henry Gale Island', 9.7, 38])

        expected = """{ "type": "FeatureCollection",
    "features":[
{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
},
{
   "type":"Feature",
   "id":6,
   "geometry":
   {"type": "Point", "coordinates": [7, 8]},
   "properties":{
      "name":"Henry Gale Island",
      "cost":9.7,
      "population":38
   }
}
]}"""
        self.assertEqual(exporter.exportFeatures([feature, feature2]),
                         expected)
예제 #3
0
    def save_vector_data(self,
                         metadata_layer,
                         post_layer_data,
                         has_transactions,
                         post_save_signal=True,
                         **kwargs):
        """Save vector editing data

        :param metadata_layer: metadata of the layer being edited
        :type metadata_layer: MetadataVectorLayer
        :param post_layer_data: post data with 'add', 'delete' etc.
        :type post_layer_data: dict
        :param has_transactions: true if the layer support transactions
        :type has_transactions: bool
        :param post_save_signal: if this is a post_save_signal call, defaults to True
        :type post_save_signal: bool, optional
        """

        # Check atomic capabilities for validation
        # -----------------------------------------------
        #for mode_editing in (EDITING_POST_DATA_ADDED, EDITING_POST_DATA_UPDATED, EDITING_POST_DATA_DELETED):

        # try to get layer model object from metatada_layer
        layer = getattr(metadata_layer, 'layer', self.layer)

        if EDITING_POST_DATA_ADDED in post_layer_data and len(
                post_layer_data[EDITING_POST_DATA_ADDED]) > 0:
            if not self.request.user.has_perm('qdjango.add_feature', layer):
                raise ValidationError(
                    _('Sorry but your user doesn\'t has \'Add Feature\' capability'
                      ))

        if EDITING_POST_DATA_DELETED in post_layer_data and len(
                post_layer_data[EDITING_POST_DATA_DELETED]) > 0:
            if not self.request.user.has_perm('qdjango.delete_feature', layer):
                raise ValidationError(
                    _('Sorry but your user doesn\'t has \'Delete Feature\' capability'
                      ))

        if EDITING_POST_DATA_UPDATED in post_layer_data and len(
                post_layer_data[EDITING_POST_DATA_UPDATED]) > 0:
            if not self.request.user.has_perm('qdjango.change_feature', layer) and \
                    not self.request.user.has_perm('qdjango.change_attr_feature', layer):
                raise ValidationError(
                    _('Sorry but your user doesn\'t has \'Change or Change Attributes Features\' capability'
                      ))

        # get initial featurelocked
        metadata_layer.lock.getInitialFeatureLockedIds()

        # get lockids from client
        metadata_layer.lock.setLockeFeaturesFromClient(
            post_layer_data['lockids'])

        # data for response
        insert_ids = list()
        lock_ids = list()

        # FIXME: check this out
        # for add check if is a metadata_layer and referenced field is a pk
        is_referenced_field_is_pk = 'referenced_layer_insert_ids' in kwargs and kwargs['referenced_layer_insert_ids'] \
            and hasattr(metadata_layer, 'referenced_field_is_pk') \
            and metadata_layer.referenced_field_is_pk

        # Get the layer
        qgis_layer = metadata_layer.qgis_layer

        for mode_editing in (EDITING_POST_DATA_ADDED,
                             EDITING_POST_DATA_UPDATED):

            if mode_editing in post_layer_data:

                for geojson_feature in post_layer_data[mode_editing]:
                    data_extra_fields = {'feature': geojson_feature}

                    # Clear any old error
                    qgis_layer.dataProvider().clearErrors()

                    # add media data
                    self.add_media_property(geojson_feature, metadata_layer)

                    # for GEOSGeometry of Django 2.2 it must add crs to feature if is not set if a geo feature
                    if metadata_layer.geometry_type != QGIS_LAYER_TYPE_NO_GEOM:
                        if geojson_feature[
                                'geometry'] and 'crs' not in geojson_feature[
                                    'geometry']:
                            geojson_feature['geometry'][
                                'crs'] = "{}:{}".format(
                                    self.layer.project.group.srid.auth_name,
                                    self.layer.project.group.srid.auth_srid)

                    # reproject data if necessary
                    if kwargs[
                            'reproject'] and metadata_layer.geometry_type != QGIS_LAYER_TYPE_NO_GEOM:
                        self.reproject_feature(geojson_feature, to_layer=True)

                    # case relation data ADD, if father referenced field is pk
                    if is_referenced_field_is_pk:
                        for newid in kwargs['referenced_layer_insert_ids']:
                            if geojson_feature['properties'][
                                    metadata_layer.
                                    referencing_field] == newid['clientid']:
                                geojson_feature['properties'][
                                    metadata_layer.
                                    referencing_field] = newid['id']

                    if mode_editing == EDITING_POST_DATA_UPDATED:
                        # control feature locked
                        if not metadata_layer.lock.checkFeatureLocked(
                                geojson_feature['id']):
                            raise Exception(
                                self.no_more_lock_feature_msg.format(
                                    geojson_feature['id'],
                                    metadata_layer.client_var))

                    # Send for validation
                    # Note that this may raise a validation error
                    pre_save_maplayer.send(self,
                                           layer_metadata=metadata_layer,
                                           mode=mode_editing,
                                           data=data_extra_fields,
                                           user=self.request.user)

                    # Validate and save
                    try:

                        original_feature = None
                        feature = QgsFeature(qgis_layer.fields())
                        if mode_editing == EDITING_POST_DATA_UPDATED:

                            # add patch for shapefile type, geojson_feature['id'] id int() instead of str()
                            # path to fix into QGIS api
                            geojson_feature[
                                'id'] = get_layer_fids_from_server_fids(
                                    [str(geojson_feature['id'])],
                                    qgis_layer)[0]
                            feature.setId(geojson_feature['id'])

                            # Get feature from data provider before update
                            original_feature = qgis_layer.getFeature(
                                geojson_feature['id'])

                        # We use this feature for geometry parsing only:
                        imported_feature = QgsJsonUtils.stringToFeatureList(
                            json.dumps(geojson_feature),
                            qgis_layer.fields(),
                            None  # UTF8 codec
                        )[0]

                        feature.setGeometry(imported_feature.geometry())

                        # There is something wrong in QGIS 3.10 (fixed in later versions)
                        # so, better loop through the fields and set attributes individually
                        for name, value in geojson_feature['properties'].items(
                        ):
                            feature.setAttribute(name, value)

                        # Loop again for set expressions value:
                        # For update store expression result to use later into update condition
                        field_expresion_values = {}
                        for qgis_field in qgis_layer.fields():
                            if qgis_field.defaultValueDefinition().expression(
                            ):
                                exp = QgsExpression(
                                    qgis_field.defaultValueDefinition(
                                    ).expression())
                                if exp.rootNode().nodeType(
                                ) != QgsExpressionNode.ntLiteral and not exp.hasParserError(
                                ):
                                    context = QgsExpressionContextUtils.createFeatureBasedContext(
                                        feature, qgis_layer.fields())
                                    context.appendScopes(
                                        QgsExpressionContextUtils.
                                        globalProjectLayerScopes(qgis_layer))
                                    result = exp.evaluate(context)
                                    if not exp.hasEvalError():
                                        feature.setAttribute(
                                            qgis_field.name(), result)

                                        # Check update if expression default value has to run also on update e not
                                        # only on insert newone
                                        if qgis_field.defaultValueDefinition(
                                        ).applyOnUpdate():
                                            field_expresion_values[
                                                qgis_field.name()] = result

                            elif qgis_field.typeName() in ('date', 'datetime',
                                                           'time'):

                                if qgis_field.typeName() == 'date':
                                    qtype = QDate
                                elif qgis_field.typeName() == 'datetime':
                                    qtype = QDateTime
                                else:
                                    qtype = QTime

                                field_idx = qgis_layer.fields().indexFromName(
                                    qgis_field.name())
                                options = qgis_layer.editorWidgetSetup(
                                    field_idx).config()

                                if 'field_iso_format' in options and not options[
                                        'field_iso_format']:
                                    if geojson_feature['properties'][
                                            qgis_field.name()]:
                                        value = qtype.fromString(
                                            geojson_feature['properties'][
                                                qgis_field.name()],
                                            options['field_format'])
                                        feature.setAttribute(
                                            qgis_field.name(), value)

                        # Call validator!
                        errors = feature_validator(feature,
                                                   metadata_layer.qgis_layer)
                        if errors:
                            raise ValidationError(errors)

                        # Save the feature
                        if mode_editing == EDITING_POST_DATA_ADDED:
                            if has_transactions:
                                if not qgis_layer.addFeature(feature):
                                    raise Exception(
                                        _('Error adding feature: %s') %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))
                            else:
                                if not qgis_layer.dataProvider().addFeature(
                                        feature):
                                    raise Exception(
                                        _('Error adding feature: %s') %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))

                                # Patch for Spatialite provider on pk
                                if qgis_layer.dataProvider().name(
                                ) == 'spatialite':
                                    pks = qgis_layer.primaryKeyAttributes()
                                    if len(pks) > 1:
                                        raise Exception(
                                            _(f'Error adding feature on Spatialite provider: '
                                              f'layer {qgis_layer.id()} has more than one pk column'
                                              ))

                                    # update pk attribute:
                                    feature.setAttribute(
                                        pks[0],
                                        server_fid(feature,
                                                   qgis_layer.dataProvider()))

                        elif mode_editing == EDITING_POST_DATA_UPDATED:
                            attr_map = {}
                            for name, value in geojson_feature[
                                    'properties'].items():
                                if name in qgis_layer.dataProvider(
                                ).fieldNameMap():
                                    if name in field_expresion_values:
                                        value = field_expresion_values[name]
                                    attr_map[qgis_layer.dataProvider().
                                             fieldNameMap()[name]] = value

                            if has_transactions:
                                if not qgis_layer.changeAttributeValues(
                                        geojson_feature['id'], attr_map):
                                    raise Exception(
                                        _('Error changing attribute values: %s'
                                          ) %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))
                                # Check for errors because of https://github.com/qgis/QGIS/issues/36583
                                if qgis_layer.dataProvider().errors():
                                    raise Exception(', '.join(
                                        qgis_layer.dataProvider().errors()))
                                if not feature.geometry().isNull(
                                ) and not qgis_layer.changeGeometry(
                                        geojson_feature['id'],
                                        feature.geometry()):
                                    raise Exception(
                                        _('Error changing geometry: %s') %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))
                            else:
                                if not qgis_layer.dataProvider(
                                ).changeAttributeValues(
                                    {geojson_feature['id']: attr_map}):
                                    raise Exception(
                                        _('Error changing attribute values: %s'
                                          ) %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))
                                if not feature.geometry().isNull(
                                ) and not qgis_layer.dataProvider(
                                ).changeGeometryValues({
                                        geojson_feature['id']:
                                        feature.geometry()
                                }):
                                    raise Exception(
                                        _('Error changing geometry: %s') %
                                        ', '.join(qgis_layer.dataProvider().
                                                  errors()))

                        to_res = {}
                        to_res_lock = {}

                        if mode_editing == EDITING_POST_DATA_ADDED:

                            # to exclude QgsFormater used into QgsJsonjExporter is necessary build by hand single json feature
                            ex = QgsJsonExporter(qgis_layer)
                            ex.setIncludeAttributes(False)

                            fnames = [f.name() for f in feature.fields()]
                            jfeature = json.loads(
                                ex.exportFeature(
                                    feature,
                                    dict(zip(fnames, feature.attributes()))))

                            to_res.update({
                                'clientid':
                                geojson_feature['id'],
                                # This might be the internal QGIS feature id (< 0)
                                'id':
                                server_fid(
                                    feature,
                                    metadata_layer.qgis_layer.dataProvider()),
                                'properties':
                                jfeature['properties']
                            })

                            # lock news:
                            to_res_lock = metadata_layer.lock.modelLock2dict(
                                metadata_layer.lock.lockFeature(server_fid(
                                    feature,
                                    metadata_layer.qgis_layer.dataProvider()),
                                                                save=True))

                        if bool(to_res):
                            insert_ids.append(to_res)
                        if bool(to_res_lock):
                            lock_ids.append(to_res_lock)

                        # Send post vase signal
                        post_save_maplayer.send(
                            self,
                            layer_metadata=metadata_layer,
                            mode=mode_editing,
                            data=data_extra_fields,
                            user=self.request.user,
                            original_feature=original_feature,
                            to_res=to_res)

                    except ValidationError as ex:
                        raise ValidationError({
                            metadata_layer.client_var: {
                                mode_editing: {
                                    'id': geojson_feature['id'],
                                    'fields': ex.detail,
                                }
                            }
                        })

                    except Exception as ex:
                        raise ValidationError({
                            metadata_layer.client_var: {
                                mode_editing: {
                                    'id': geojson_feature['id'],
                                    'fields': str(ex),
                                }
                            }
                        })

        # erasing feature if to do
        if EDITING_POST_DATA_DELETED in post_layer_data:

            fids = post_layer_data[EDITING_POST_DATA_DELETED]

            # get feature fids from server fids from client.
            fids = get_layer_fids_from_server_fids([str(id) for id in fids],
                                                   qgis_layer)

            for feature_id in fids:

                # control feature locked
                if not metadata_layer.lock.checkFeatureLocked(str(feature_id)):
                    raise Exception(
                        self.no_more_lock_feature_msg.format(
                            feature_id, metadata_layer.client_var))

                # Get feature to delete
                ex = QgsJsonExporter(qgis_layer)
                deleted_feature = ex.exportFeature(
                    qgis_layer.getFeature(feature_id))

                pre_delete_maplayer.send(self,
                                         layer_metatada=metadata_layer,
                                         data=deleted_feature,
                                         user=self.request.user)

                qgis_layer.dataProvider().clearErrors()

                if has_transactions:
                    if not qgis_layer.deleteFeatures(
                        [feature_id]) or qgis_layer.dataProvider().errors():
                        raise Exception(
                            _('Cannot delete feature: %s') %
                            ', '.join(qgis_layer.dataProvider().errors()))
                else:
                    if not qgis_layer.dataProvider().deleteFeatures(
                        [feature_id]) or qgis_layer.dataProvider().errors():
                        raise Exception(
                            _('Cannot delete feature: %s') %
                            ', '.join(qgis_layer.dataProvider().errors()))

        return insert_ids, lock_ids
예제 #4
0
    def testJSONExporter(self):
        """ test converting features to GeoJSON """
        fields = QgsFields()
        fields.append(QgsField("name", QVariant.String))
        fields.append(QgsField("cost", QVariant.Double))
        fields.append(QgsField("population", QVariant.Int))

        feature = QgsFeature(fields, 5)
        feature.setGeometry(QgsGeometry(QgsPoint(5, 6)))
        feature.setAttributes(['Valsier Peninsula', 6.8, 198])

        exporter = QgsJsonExporter()

        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        # test with linestring for bbox inclusion
        l = QgsLineString()
        l.setPoints([QgsPoint(5, 6), QgsPoint(15, 16)])
        feature.setGeometry(QgsGeometry(QgsLineString(l)))

        expected = """{
   "type":"Feature",
   "id":5,
   "bbox":[5, 6, 15, 16],
   "geometry":
   {"type": "LineString", "coordinates": [ [5, 6], [15, 16]]},
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        # test that precision is respected
        feature.setGeometry(QgsGeometry(QgsPoint(5.444444444, 6.333333333)))
        exporter.setPrecision(3)
        self.assertEqual(exporter.precision(), 3)
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5.444, 6.333]},
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)
        feature.setGeometry(QgsGeometry(QgsPoint(5, 6)))
        exporter.setPrecision(17)

        # test that attribute subset is respected
        exporter.setAttributes([0, 2])
        self.assertEqual(exporter.attributes(), [0, 2])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula",
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        exporter.setAttributes([1])
        self.assertEqual(exporter.attributes(), [1])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "cost":6.8
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)
        exporter.setAttributes([])

        # text excluding attributes

        exporter.setExcludedAttributes([1])
        self.assertEqual(exporter.excludedAttributes(), [1])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula",
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        exporter.setExcludedAttributes([1, 2])
        self.assertEqual(exporter.excludedAttributes(), [1, 2])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "name":"Valsier Peninsula"
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        exporter.setExcludedAttributes([0, 1, 2])
        self.assertEqual(exporter.excludedAttributes(), [0, 1, 2])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":null
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        # test that excluded attributes take precedence over included

        exporter.setAttributes([1, 2])
        exporter.setExcludedAttributes([0, 1])
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":{
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        exporter.setAttributes([])
        exporter.setExcludedAttributes([])

        # test excluding geometry
        exporter.setIncludeGeometry(False)
        self.assertEqual(exporter.includeGeometry(), False)
        feature.setGeometry(QgsGeometry(QgsLineString(l)))

        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":null,
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)
        exporter.setIncludeGeometry(True)

        feature.setGeometry(QgsGeometry(QgsPoint(5, 6)))

        # test excluding attributes
        exporter.setIncludeAttributes(False)
        self.assertEqual(exporter.includeAttributes(), False)
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":
   {"type": "Point", "coordinates": [5, 6]},
   "properties":null
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)

        exporter.setIncludeGeometry(False)
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":null,
   "properties":null
}"""
        self.assertEqual(exporter.exportFeature(feature), expected)
        exporter.setIncludeAttributes(True)

        # test overriding ID
        expected = """{
   "type":"Feature",
   "id":29,
   "geometry":null,
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198
   }
}"""
        self.assertEqual(exporter.exportFeature(feature, id=29), expected)

        # test injecting extra attributes
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":null,
   "properties":{
      "name":"Valsier Peninsula",
      "cost":6.8,
      "population":198,
      "extra":"val1",
      "extra2":2
   }
}"""
        self.assertEqual(
            exporter.exportFeature(feature,
                                   extraProperties={
                                       "extra": "val1",
                                       "extra2": 2
                                   }), expected)

        exporter.setIncludeAttributes(False)
        expected = """{
   "type":"Feature",
   "id":5,
   "geometry":null,
   "properties":{
      "extra":"val1",
      "extra2":{"nested_map":5,
"nested_map2":"val"},
      "extra3":[1,2,3]
   }
}"""
        expected2 = """{
   "type":"Feature",
   "id":5,
   "geometry":null,
   "properties":{
      "extra":"val1",
      "extra2":{"nested_map":5,"nested_map2":"val"},
      "extra3":[1,2,3]
   }
}"""
        exp_f = exporter.exportFeature(feature,
                                       extraProperties={
                                           "extra": "val1",
                                           "extra2": {
                                               "nested_map": 5,
                                               "nested_map2": "val"
                                           },
                                           "extra3": [1, 2, 3]
                                       })
        self.assertTrue(exp_f == expected or exp_f == expected2)
        exporter.setIncludeGeometry(True)
예제 #5
0
    def test_expression_eval(self):

        self.assertEqual(expression_eval('1'), 1)
        self.assertEqual(expression_eval('1=2'), False)

        layer = Layer.objects.get(title='world')

        # Errors
        with self.assertRaises(ExpressionProjectError) as ex:
            expression_eval('1', project_id='9999', qgs_layer_id='9999')

        with self.assertRaises(ExpressionLayerError) as ex:
            expression_eval('1',
                            project_id=layer.project_id,
                            qgs_layer_id='9999')

        with self.assertRaises(ExpressionParseError) as ex:
            expression_eval('dsa hdshk == t')

        with self.assertRaises(ExpressionEvalError) as ex:
            expression_eval('not_valid=2')

        with self.assertRaises(ExpressionForbiddenError) as ex:
            expression_eval('@qgis_version')

        with self.assertRaises(ExpressionForbiddenError) as ex:
            expression_eval('env(\'USER\')')

        # Test form data
        feature = next(layer.qgis_layer.getFeatures())
        exp = QgsJsonExporter(layer.qgis_layer)
        form_data = exp.exportFeature(feature)

        self.assertEqual(
            expression_eval('current_value(\'APPROX\')',
                            project_id=layer.project_id,
                            qgs_layer_id=layer.qgs_layer_id,
                            form_data=json.loads(form_data)), 9705000)

        self.assertEqual(
            expression_eval('"APPROX"',
                            project_id=layer.project_id,
                            qgs_layer_id=layer.qgs_layer_id,
                            form_data=json.loads(form_data)), 9705000)

        self.assertEqual(
            expression_eval('APPROX',
                            project_id=layer.project_id,
                            qgs_layer_id=layer.qgs_layer_id,
                            form_data=json.loads(form_data)), 9705000)

        self.assertEqual(
            expression_eval('APPROX = 9705000',
                            project_id=layer.project_id,
                            qgs_layer_id=layer.qgs_layer_id,
                            form_data=json.loads(form_data)), True)

        self.assertEqual(
            expression_eval('APPROX = 99999',
                            project_id=layer.project_id,
                            qgs_layer_id=layer.qgs_layer_id,
                            form_data=json.loads(form_data)), False)
예제 #6
0
    def response_data_mode(self, request, export_features=False):
        """
        Query layer and return data
        :param request: DjangoREST API request object
        :param formatter: Boolean, default False, True for to use QgsJsonExport.exportFeatures method
        :return: response dict data
        """

        # Create the QGIS feature request, it will be passed through filters
        # and to the final QGIS API get features call.
        qgis_feature_request = QgsFeatureRequest()

        # Prepare arguments for the get feature call
        kwargs = {}

        # Apply filter backends, store original subset string
        original_subset_string = self.metadata_layer.qgis_layer.subsetString()
        if hasattr(self, 'filter_backends'):
            for backend in self.filter_backends:
                backend().apply_filter(request, self.metadata_layer.qgis_layer, qgis_feature_request, self)

        # Paging cannot be a backend filter
        if 'page' in request.query_params:
            kwargs['page'] = request.query_params.get('page')
            kwargs['page_size'] = request.query_params.get('page_size', 10)

        self.features = get_qgis_features(
            self.metadata_layer.qgis_layer, qgis_feature_request, **kwargs)
        ex = QgsJsonExporter(self.metadata_layer.qgis_layer)

        # If 'unique' request params is set,
        # api return a list of unique
        # field name sent with 'unique' param.
        # --------------------------------------
        # IDEA:     for big data it'll be iterate over features to get unique
        #           c++ iteration is fast. Instead memory layer fith to much features can be a problem.
        if 'unique' in request.query_params:

            vl = QgsVectorLayer(QgsWkbTypes.displayString(self.metadata_layer.qgis_layer.wkbType()),
                                "temporary_vector", "memory")
            pr = vl.dataProvider()

            # add fields
            pr.addAttributes(self.metadata_layer.qgis_layer.fields())
            vl.updateFields()  # tell the vector layer to fetch changes from the provider

            res = pr.addFeatures(self.features)

            uniques = vl.uniqueValues(
                self.metadata_layer.qgis_layer.fields().indexOf(request.query_params.get('unique'))
            )

            values = []
            for u in uniques:
                try:
                    if u:
                        values.append(json.loads(QgsJsonUtils.encodeValue(u)))
                except Exception as e:
                    logger.error(f'Response vector widget unique: {e}')
                    continue

            self.results.update({
                'data': values,
                'count': len(values)
            })

            del(vl)

        else:

            # patch for return GeoJson feature with CRS different from WGS84
            # TODO: use .setTransformGeometries( false ) with QGIS >= 3.12
            ex.setSourceCrs(QgsCoordinateReferenceSystem('EPSG:4326'))

            # check for formatter query url param and check if != 0
            if 'formatter' in request.query_params:
                formatter = request.query_params.get('formatter')
                if formatter.isnumeric() and int(formatter) == 0:
                    export_features = False
                else:
                    export_features = True

            if export_features:
                feature_collection = json.loads(ex.exportFeatures(self.features))
            else:

                # to exclude QgsFormater used into QgsJsonjExporter is necessary build by hand single json feature
                ex.setIncludeAttributes(False)

                feature_collection = {
                    'type': 'FeatureCollection',
                    'features': []
                }

                for feature in self.features:
                    fnames = [f.name() for f in feature.fields()]
                    feature_collection['features'].append(
                        json.loads(ex.exportFeature(feature, dict(zip(fnames, feature.attributes()))))
                    )



            # FIXME: QGIS api reprojecting?
            # Reproject if necessary
            # if self.reproject:
            #    self.reproject_featurecollection(feature_collection)

            # Change media
            self.change_media(feature_collection)

            self.results.update(APIVectorLayerStructure(**{
                'data': feature_collection,
                'count': count_qgis_features(self.metadata_layer.qgis_layer, qgis_feature_request, **kwargs),
                'geometryType': self.metadata_layer.geometry_type,
            }).as_dict())

            # FIXME: add extra fields data by signals and receivers
            # FIXME: featurecollection = post_serialize_maplayer.send(layer_serializer, layer=self.layer_name)
            # FIXME: Not sure how to map this to the new QGIS API

        # Restore the original subset string
        self.metadata_layer.qgis_layer.setSubsetString(original_subset_string)
예제 #7
0
파일: views.py 프로젝트: nstoykov/g3w-admin
    def response_data_mode(self, request, export_features=False):
        """
        Query layer and return data
        :param request: DjangoREST API request object
        :param formatter: Boolean, default False, True for to use QgsJsonExport.exportFeatures method
        :return: response dict data
        """

        # Create the QGIS feature request, it will be passed through filters
        # and to the final QGIS API get features call.
        qgis_feature_request = QgsFeatureRequest()

        # Prepare arguments for the get feature call
        kwargs = {}

        # Apply filter backends, store original subset string
        original_subset_string = self.metadata_layer.qgis_layer.subsetString()
        if hasattr(self, 'filter_backends'):
            try:
                for backend in self.filter_backends:
                    backend().apply_filter(request, self.metadata_layer,
                                           qgis_feature_request, self)
            except Exception as e:
                raise APIException(e)

        # Paging cannot be a backend filter
        if 'page' in request.query_params:
            kwargs['page'] = request.query_params.get('page')
            kwargs['page_size'] = request.query_params.get('page_size', 10)

        # Make sure we have all attrs we need to build the server FID
        provider = self.metadata_layer.qgis_layer.dataProvider()
        if qgis_feature_request.flags() & QgsFeatureRequest.SubsetOfAttributes:
            attrs = qgis_feature_request.subsetOfAttributes()
            for attr_idx in provider.pkAttributeIndexes():
                if attr_idx not in attrs:
                    attrs.append(attr_idx)
            qgis_feature_request.setSubsetOfAttributes(attrs)

        self.features = get_qgis_features(self.metadata_layer.qgis_layer,
                                          qgis_feature_request, **kwargs)

        # Reproject feature if layer CRS != Project CRS
        if self.reproject:
            for f in self.features:
                self.reproject_feature(f)

        ex = QgsJsonExporter(self.metadata_layer.qgis_layer)

        # If 'unique' request params is set,
        # api return a list of unique
        # field name sent with 'unique' param.
        # --------------------------------------
        # IDEA:     for big data it'll be iterate over features to get unique
        #           c++ iteration is fast. Instead memory layer with too many features can be a problem.
        if 'unique' in request.query_params:

            vl = QgsVectorLayer(
                QgsWkbTypes.displayString(
                    self.metadata_layer.qgis_layer.wkbType()),
                "temporary_vector", "memory")
            pr = vl.dataProvider()

            # add fields
            pr.addAttributes(self.metadata_layer.qgis_layer.fields())
            vl.updateFields(
            )  # tell the vector layer to fetch changes from the provider

            res = pr.addFeatures(self.features)

            uniques = vl.uniqueValues(
                self.metadata_layer.qgis_layer.fields().indexOf(
                    request.query_params.get('unique')))

            values = []
            for u in uniques:
                try:
                    if u:
                        values.append(json.loads(QgsJsonUtils.encodeValue(u)))
                except Exception as e:
                    logger.error(f'Response vector widget unique: {e}')
                    continue

            # sort values
            values.sort()
            self.results.update({'data': values, 'count': len(values)})

            del (vl)

        else:

            ex.setTransformGeometries(False)

            # check for formatter query url param and check if != 0
            if 'formatter' in request.query_params:
                formatter = request.query_params.get('formatter')
                if formatter.isnumeric() and int(formatter) == 0:
                    export_features = False
                else:
                    export_features = True

            if export_features:
                feature_collection = json.loads(
                    ex.exportFeatures(self.features))
            else:

                # to exclude QgsFormater used into QgsJsonExporter is necessary build by hand single json feature
                ex.setIncludeAttributes(False)

                feature_collection = {
                    'type': 'FeatureCollection',
                    'features': []
                }

                for feature in self.features:
                    fnames = []
                    date_fields = []
                    for f in feature.fields():
                        fnames.append(f.name())
                        if f.typeName() in ('date', 'datetime', 'time'):
                            date_fields.append(f)

                    jsonfeature = json.loads(
                        ex.exportFeature(
                            feature, dict(zip(fnames, feature.attributes()))))

                    # Update date and datetime fields value if widget is active
                    if len(date_fields) > 0:
                        for f in date_fields:
                            field_idx = self.metadata_layer.qgis_layer.fields(
                            ).indexFromName(f.name())
                            options = self.metadata_layer.qgis_layer.editorWidgetSetup(
                                field_idx).config()
                            if 'field_iso_format' in options and not options[
                                    'field_iso_format']:
                                try:
                                    jsonfeature['properties'][f.name()] = feature.attribute(f.name())\
                                        .toString(options['field_format'])
                                except:
                                    pass

                    feature_collection['features'].append(jsonfeature)

            # Change media
            self.change_media(feature_collection)

            # Patch feature IDs with server featureIDs
            fids_map = {}
            for f in self.features:
                fids_map[f.id()] = server_fid(f, provider)

            for i in range(len(feature_collection['features'])):
                f = feature_collection['features'][i]
                f['id'] = fids_map[f['id']]

            self.results.update(
                APIVectorLayerStructure(
                    **{
                        'data':
                        feature_collection,
                        'count':
                        count_qgis_features(self.metadata_layer.qgis_layer,
                                            qgis_feature_request, **kwargs),
                        'geometryType':
                        self.metadata_layer.geometry_type,
                    }).as_dict())

            # FIXME: add extra fields data by signals and receivers
            # FIXME: featurecollection = post_serialize_maplayer.send(layer_serializer, layer=self.layer_name)
            # FIXME: Not sure how to map this to the new QGIS API

        # Restore the original subset string
        self.metadata_layer.qgis_layer.setSubsetString(original_subset_string)
예제 #8
0
    def virtualFields(self, params: Dict[str,
                                         str], response: QgsServerResponse,
                      project: QgsProject) -> None:
        """ Get virtual fields for features
        In parameters:
            LAYER=wms-layer-name
            VIRTUALS={"key1": "first expression", "key2": "second expression"}
            // optionals
            FILTER=An expression to filter layer
            FIELDS=list of requested field separated by comma
            WITH_GEOMETRY=False
        """
        layername = params.get('LAYER', '')
        if not layername:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'VirtualFields' REQUEST: LAYER parameter is mandatory",
                400)

        # get layer
        layer = findVectorLayer(layername, project)
        # layer not found
        if not layer:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid LAYER parameter for 'VirtualFields': {} provided".
                format(layername), 400)

        # get virtuals
        virtuals = params.get('VIRTUALS', '')
        if not virtuals:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'VirtualFields' REQUEST: VIRTUALS parameter is mandatory",
                400)

        # try to load virtuals dict
        vir_json = None
        try:
            vir_json = json.loads(virtuals)
        except Exception:
            QgsMessageLog.logMessage(
                "JSON loads virtuals '{}' exception:\n{}".format(
                    virtuals, traceback.format_exc()), "lizmap", Qgis.Critical)
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'VirtualFields' REQUEST: VIRTUALS '{}' are not well formed"
                .format(virtuals), 400)

        if not isinstance(vir_json, dict):
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'VirtualFields' REQUEST: VIRTUALS '{}' are not well formed"
                .format(virtuals), 400)

        # create expression context
        exp_context = QgsExpressionContext()
        exp_context.appendScope(QgsExpressionContextUtils.globalScope())
        exp_context.appendScope(
            QgsExpressionContextUtils.projectScope(project))
        exp_context.appendScope(QgsExpressionContextUtils.layerScope(layer))

        # create distance area context
        da = QgsDistanceArea()
        da.setSourceCrs(layer.crs(), project.transformContext())
        da.setEllipsoid(project.ellipsoid())

        # parse virtuals
        exp_map = {}
        exp_parser_errors = []
        for k, e in vir_json.items():
            exp = QgsExpression(e)
            exp.setGeomCalculator(da)
            exp.setDistanceUnits(project.distanceUnits())
            exp.setAreaUnits(project.areaUnits())

            if exp.hasParserError():
                exp_parser_errors.append('Error "{}": {}'.format(
                    e, exp.parserErrorString()))
                continue

            if not exp.isValid():
                exp_parser_errors.append('Expression not valid "{}"'.format(e))
                continue

            exp.prepare(exp_context)
            exp_map[k] = exp

        # expression parser errors found
        if exp_parser_errors:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid VIRTUALS for 'VirtualFields':\n{}".format(
                    '\n'.join(exp_parser_errors)), 400)

        req = QgsFeatureRequest()

        # get filter
        req_filter = params.get('FILTER', '')
        if req_filter:
            req_exp = QgsExpression(req_filter)
            req_exp.setGeomCalculator(da)
            req_exp.setDistanceUnits(project.distanceUnits())
            req_exp.setAreaUnits(project.areaUnits())

            if req_exp.hasParserError():
                raise ExpressionServiceError(
                    "Bad request error",
                    "Invalid FILTER for 'VirtualFields' Error \"{}\": {}".
                    format(req_filter, req_exp.parserErrorString()), 400)

            if not req_exp.isValid():
                raise ExpressionServiceError(
                    "Bad request error",
                    "Invalid FILTER for 'VirtualFields' Expression not valid \"{}\""
                    .format(req_filter), 400)

            req_exp.prepare(exp_context)
            req = QgsFeatureRequest(req_exp, exp_context)

        # With geometry
        withGeom = params.get('WITH_GEOMETRY',
                              '').lower() in ['true', '1', 't']
        if not withGeom:
            req.setFlags(QgsFeatureRequest.NoGeometry)

        # Fields
        pkAttributes = layer.primaryKeyAttributes()
        attributeList = [i for i in pkAttributes]
        fields = layer.fields()
        r_fields = [
            f.strip() for f in params.get('FIELDS', '').split(',') if f
        ]
        for f in r_fields:
            attributeList.append(fields.indexOf(f))

        # response
        response.setStatusCode(200)
        response.setHeader("Content-Type", "application/json")
        response.write('{ "type": "FeatureCollection","features":[')
        response.flush()

        jsonExporter = QgsJsonExporter(layer)
        if attributeList:
            jsonExporter.setAttributes(attributeList)

        separator = ''
        for feat in layer.getFeatures(req):
            fid = layername + '.' + getServerFid(feat, pkAttributes)

            extra = {}

            # Update context
            exp_context.setFeature(feat)
            exp_context.setFields(feat.fields())

            # Evaluate expressions for virtual fields
            errors = {}
            for k, exp in exp_map.items():
                value = exp.evaluate(exp_context)
                if exp.hasEvalError():
                    extra[k] = None
                    errors[k] = exp.evalErrorString()
                else:
                    extra[k] = json.loads(QgsJsonUtils.encodeValue(value))
                    errors[k] = exp.expression()

            response.write(separator +
                           jsonExporter.exportFeature(feat, extra, fid))
            response.flush()
            separator = ',\n'
        response.write(']}')
        return
예제 #9
0
    def getFeatureWithFormScope(self, params: Dict[str, str],
                                response: QgsServerResponse,
                                project: QgsProject) -> None:
        """ Get filtered features with a form scope
        In parameters:
            LAYER=wms-layer-name
            FILTER=An expression to filter layer
            FORM_FEATURE={"type": "Feature", "geometry": {}, "properties": {}}
            // optionals
            FIELDS=list of requested field separated by comma
            WITH_GEOMETRY=False
        """
        layername = params.get('LAYER', '')
        if not layername:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: LAYER parameter is mandatory",
                400)

        # get layer
        layer = findVectorLayer(layername, project)
        # layer not found
        if not layer:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid LAYER parameter for 'VirtualField': {} provided".
                format(layername), 400)

        # get filter
        exp_filter = params.get('FILTER', '')
        if not exp_filter:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: FILTER parameter is mandatory",
                400)

        # get form feature
        form_feature = params.get('FORM_FEATURE', '')
        if not form_feature:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: FORM_FEATURE parameter is mandatory",
                400)

        # Check features
        geojson = {}
        try:
            geojson = json.loads(form_feature)
        except Exception:
            QgsMessageLog.logMessage(
                "JSON loads form feature '{}' exception:\n{}".format(
                    form_feature, traceback.format_exc()), "lizmap",
                Qgis.Critical)
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: FORM_FEATURE '{}' are not well formed"
                .format(form_feature), 400)

        if not geojson or not isinstance(geojson, dict):
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: FORM_FEATURE '{}' are not well formed"
                .format(form_feature), 400)

        if ('type' not in geojson) or geojson['type'] != 'Feature':
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid 'GetFeatureWithFormScope' REQUEST: FORM_FEATURE '{}' are not well formed: type not defined or not Feature."
                .format(form_feature), 400)

        # try to load form feature
        # read fields
        form_feature_fields = QgsJsonUtils.stringToFields(
            form_feature, QTextCodec.codecForName("UTF-8"))
        # read features
        form_feature_list = QgsJsonUtils.stringToFeatureList(
            form_feature, form_feature_fields,
            QTextCodec.codecForName("UTF-8"))

        # features not well formed
        if not form_feature_list:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid FORM_FEATURE for 'GetFeatureWithFormScope': not GeoJSON feature provided\n{}"
                .format(form_feature), 400)

        if len(form_feature_list) != 1:
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid FORM_FEATURE for 'GetFeatureWithFormScope': not GeoJSON feature provided\n{}"
                .format(form_feature), 400)

        # Get the form feature
        form_feat = form_feature_list[0]

        # create expression context
        exp_context = QgsExpressionContext()
        exp_context.appendScope(QgsExpressionContextUtils.globalScope())
        exp_context.appendScope(
            QgsExpressionContextUtils.projectScope(project))
        exp_context.appendScope(QgsExpressionContextUtils.layerScope(layer))
        exp_context.appendScope(QgsExpressionContextUtils.formScope(form_feat))

        # create distance area context
        da = QgsDistanceArea()
        da.setSourceCrs(layer.crs(), project.transformContext())
        da.setEllipsoid(project.ellipsoid())

        # Get filter expression
        exp_f = QgsExpression(exp_filter)
        exp_f.setGeomCalculator(da)
        exp_f.setDistanceUnits(project.distanceUnits())
        exp_f.setAreaUnits(project.areaUnits())

        if exp_f.hasParserError():
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid FILTER for 'GetFeatureWithFormScope': Error \"{}\": {}"
                .format(exp_filter, exp_f.parserErrorString()), 400)

        if not exp_f.isValid():
            raise ExpressionServiceError(
                "Bad request error",
                "Invalid FILTER for 'GetFeatureWithFormScope': Expression not valid \"{}\""
                .format(exp_filter), 400)

        exp_f.prepare(exp_context)

        req = QgsFeatureRequest(exp_f, exp_context)

        # With geometry
        withGeom = params.get('WITH_GEOMETRY',
                              '').lower() in ['true', '1', 't']
        if not withGeom:
            req.setFlags(QgsFeatureRequest.NoGeometry)

        # Fields
        pkAttributes = layer.primaryKeyAttributes()
        attributeList = [i for i in pkAttributes]
        fields = layer.fields()
        r_fields = [
            f.strip() for f in params.get('FIELDS', '').split(',') if f
        ]
        for f in r_fields:
            attributeList.append(fields.indexOf(f))

        # response
        response.setStatusCode(200)
        response.setHeader("Content-Type", "application/json")
        response.write('{ "type": "FeatureCollection","features":[')
        response.flush()

        jsonExporter = QgsJsonExporter(layer)
        if attributeList:
            jsonExporter.setAttributes(attributeList)

        separator = ''
        for feat in layer.getFeatures(req):
            fid = layername + '.' + getServerFid(feat, pkAttributes)
            response.write(separator +
                           jsonExporter.exportFeature(feat, {}, fid))
            response.flush()
            separator = ',\n'
        response.write(']}')
        return