def input_form(self):
input_form = super(QgisEditTypeValueRelation, self).input_form
if self.FilterExpression != '':
exp = QgsExpression(self.FilterExpression)
filter_expression = {
'expression': exp.expression(),
'referenced_columns': list(exp.referencedColumns()),
'referenced_functions': list(exp.referencedFunctions())
}
# For current_values function in filter expression get parameter field fo it
if "current_value" in filter_expression['referenced_functions']:
groups = re.findall(r'current_value\(\'(.*?)\'\)|(\w+=\w+)',
filter_expression['expression'])
filter_expression['referencing_fields'] = [
g[0] for g in groups
]
else:
filter_expression = None
# add params for get value
input_form['input']['options'].update({
'key':
self.Value,
'value':
self.Key,
'usecompleter':
True if self.UseCompleter == '1' or self.UseCompleter == 'true'
else False,
'layer_id':
self.Layer,
'loading': {
'state': None
},
'filter_expression':
filter_expression,
})
return input_form
def expression_eval(expression_text,
project_id=None,
qgs_layer_id=None,
form_data=None,
formatter=0):
"""Evaluates a QgsExpression and returns the result
:param expression_text: The QgsExpression text
:type expression_text: str
:param project_id: ID of the qdjango project, defaults to None
:type project_id: int, optional
:param qgs_layer_id: ID of the QGIS Layer, defaults to None
:type qgslayer_id: str, optional
:param form_data: A dictionary that maps to a GeoJSON representation of the feature currently edited in the form
:type form_data: dict, optional
:param formatter: Indicate if form_data values contains formatter values or original features value.
:type formatter: int, optional
"""
expression = QgsExpression(expression_text)
expression_context = QgsExpressionContext()
layer = None
for func_name in expression.referencedFunctions():
if func_name in FORBIDDEN_FUNCTIONS:
raise ExpressionForbiddenError(
_('Function "{}" is not allowed for security reasons!').format(
func_name))
for var_name in expression.referencedVariables():
if var_name in FORBIDDEN_VARIABLES:
raise ExpressionForbiddenError(
_('Variable "{}" is not allowed for security reasons!').format(
var_name))
if project_id is not None:
try:
project = Project.objects.get(pk=project_id)
if qgs_layer_id is not None:
try:
layer = project.layer_set.get(qgs_layer_id=qgs_layer_id)
except Layer.DoesNotExist:
raise ExpressionLayerError(
_('QGIS layer with id "{}" could not be found!').
format(qgs_layer_id))
expression_contex = QgsExpressionContextUtils.globalProjectLayerScopes(
layer.qgis_layer)
else:
expression_contex = QgsExpressionContextUtils.globalScope()
expression_context.appendScope(
QgsExpressionContextUtils.projectScope(
project.qgis_project))
except Project.DoesNotExist:
raise ExpressionProjectError(
_('QDjango project with id "{}" could not be found!').format(
project_id))
else:
expression_contex = QgsExpressionContextUtils.globalScope()
if form_data is not None:
if layer is None:
raise ExpressionLayerError(
_('A valid QGIS layer is required to process form data!'))
try:
# Case by formatter
# formatter == 1 : get featureid from layer, usually must be used with formatter form_data
# formatter == 0 : default behavior
if formatter == 0:
fields = layer.qgis_layer.fields()
form_feature = QgsJsonUtils.stringToFeatureList(
json.dumps(form_data), fields, None)[0]
# Set attributes manually because QgsJsonUtils does not respect order
for k, v in form_data['properties'].items():
form_feature.setAttribute(k, v)
else:
qgis_feature_request = QgsFeatureRequest()
exp = expression_from_server_fids(
[form_data['id']], layer.qgis_layer.dataProvider())
qgis_feature_request.combineFilterExpression(exp)
form_feature = get_qgis_features(layer.qgis_layer,
qgis_feature_request)[0]
expression_context.appendScope(
QgsExpressionContextUtils.formScope(form_feature))
expression_context.setFeature(form_feature)
except:
raise ExpressionFormDataError()
valid, errors = expression.checkExpression(expression_text,
expression_context)
if not valid:
raise ExpressionParseError(errors)
result = expression.evaluate(expression_context)
if expression.hasEvalError():
raise ExpressionEvalError(expression.evalErrorString())
return result
