def apply_filter(self, request, metadata_layer, qgis_feature_request, view): if request.data and request.data.get('expression'): qgis_feature_request.combineFilterExpression( request.data.get('expression')) if request.data.get('form_data') and request.data.get( 'qgs_layer_id'): try: project = Layer.objects.get( pk=metadata_layer.layer_id).project layer = Layer.objects.get( project=project, qgs_layer_id=request.data.get('qgs_layer_id')) fields = layer.qgis_layer.fields() form_data = request.data.get('form_data') form_feature = QgsJsonUtils.stringToFeatureList( json.dumps(form_data), fields, None)[0] for k, v in form_data['properties'].items(): form_feature.setAttribute(k, v) qgis_feature_request.expressionContext().appendScope( QgsExpressionContextUtils.formScope(form_feature)) except: raise Exception("Layer or project could not be found!")
def get_feature_with_form_scope(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 """ layer_name = params.get('LAYER', '') if not layer_name: raise ExpressionServiceError( "Bad request error", "Invalid 'GetFeatureWithFormScope' REQUEST: LAYER parameter is mandatory", 400) # get layer layer = find_vector_layer(layer_name, project) # layer not found if not layer: raise ExpressionServiceError( "Bad request error", "Invalid LAYER parameter for 'VirtualField': {} provided".format(layer_name), 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 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 with_geom = params.get('WITH_GEOMETRY', '').lower() in ['true', '1', 't'] if not with_geom: req.setFlags(QgsFeatureRequest.NoGeometry) # Fields pk_attributes = layer.primaryKeyAttributes() attribute_list = [i for i in pk_attributes] fields = layer.fields() r_fields = [f.strip() for f in params.get('FIELDS', '').split(',') if f] for f in r_fields: attribute_list.append(fields.indexOf(f)) # response response.setStatusCode(200) response.setHeader("Content-Type", "application/json") response.write('{ "type": "FeatureCollection","features":[') response.flush() json_exporter = QgsJsonExporter(layer) if attribute_list: json_exporter.setAttributes(attribute_list) separator = '' for feat in layer.getFeatures(req): fid = layer_name + '.' + get_server_fid(feat, pk_attributes) response.write(separator + json_exporter.exportFeature(feat, {}, fid)) response.flush() separator = ',\n' response.write(']}') return
def replace_expression_text(params: Dict[str, str], response: QgsServerResponse, project: QgsProject) -> None: """ Replace expression texts against layer or features In parameters: LAYER=wms-layer-name STRING=A string with expression between [% and %] or STRINGS=["first string with expression", "second string with expression"] or STRINGS={"key1": "first string with expression", "key2": "second string with expression"} // optionals FEATURE={"type": "Feature", "geometry": {}, "properties": {}} or FEATURES=[{"type": "Feature", "geometry": {}, "properties": {}}, {"type": "Feature", "geometry": {}, "properties": {}}] FORM_SCOPE=boolean to add formScope based on provided features """ layername = params.get('LAYER', '') if not layername: raise ExpressionServiceError( "Bad request error", "Invalid 'ReplaceExpressionText' REQUEST: LAYER parameter is mandatory", 400) # get layer layer = find_vector_layer(layername, project) # layer not found if not layer: raise ExpressionServiceError( "Bad request error", "Invalid LAYER parameter for 'ReplaceExpressionText': {} provided".format(layername), 400) # get strings strings = params.get('STRINGS', '') if not strings: the_string = params.get('STRING', '') if not the_string: raise ExpressionServiceError( "Bad request error", "Invalid 'ReplaceExpressionText' REQUEST: STRING or STRINGS parameter is mandatory", 400) strings = '["{}"]'.format(the_string) # try to load expressions list or dict try: str_json = json.loads(strings) except Exception: QgsMessageLog.logMessage( "JSON loads strings '{}' exception:\n{}".format(strings, traceback.format_exc()), "lizmap", Qgis.Critical) raise ExpressionServiceError( "Bad request error", "Invalid 'ReplaceExpressionText' REQUEST: STRINGS '{}' are not well formed".format(strings), 400) # get features features = params.get('FEATURES', '') if not features: feature = params.get('FEATURE', '') if feature: features = '[' + feature + ']' # 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()) # organized strings str_map = {} str_items = [] if isinstance(str_json, list): str_items = enumerate(str_json) elif isinstance(str_json, dict): str_items = str_json.items() for k, s in str_items: str_map[k] = s # create the body body = { 'status': 'success', 'results': [], 'errors': [], 'features': 0 } # without features just replace expression string with layer context if not features: result = {} for k, s in str_map.items(): value = QgsExpression.replaceExpressionText(s, exp_context, da) result[k] = json.loads(QgsJsonUtils.encodeValue(value)) body['results'].append(result) write_json_response(body, response) return # Check features try: geojson = json.loads(features) except Exception: QgsMessageLog.logMessage( "JSON loads features '{}' exception:\n{}".format(features, traceback.format_exc()), "lizmap", Qgis.Critical) raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed".format(features), 400) if not geojson or not isinstance(geojson, list) or len(geojson) == 0: raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed".format(features), 400) if ('type' not in geojson[0]) or geojson[0]['type'] != 'Feature': raise ExpressionServiceError( "Bad request error", ("Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed: type not defined or not " "Feature.").format(features), 400) # try to load features # read fields feature_fields = QgsJsonUtils.stringToFields( '{ "type": "FeatureCollection","features":' + features + '}', QTextCodec.codecForName("UTF-8")) # read features feature_list = QgsJsonUtils.stringToFeatureList( '{ "type": "FeatureCollection","features":' + features + '}', feature_fields, QTextCodec.codecForName("UTF-8")) # features not well formed if not feature_list: raise ExpressionServiceError( "Bad request error", ("Invalid FEATURES for 'ReplaceExpressionText': not GeoJSON features array " "provided\n{}").format(features), 400) # Extend layer fields with this provided in GeoJSON Features feat_fields = QgsFields(layer.fields()) feat_fields.extend(feature_fields) # form scope add_form_scope = params.get('FORM_SCOPE', '').lower() in ['true', '1', 't'] # loop through provided features to replace expression strings for f in feature_list: # clone the features with all attributes # those defined in layer + fields from GeoJSON Features feat = QgsFeature(feat_fields) feat.setGeometry(f.geometry()) for field in f.fields(): field_name = field.name() if feat_fields.indexOf(field_name) != -1: feat.setAttribute(field_name, f[field_name]) # Add form scope to expression context if add_form_scope: exp_context.appendScope(QgsExpressionContextUtils.formScope(feat)) exp_context.setFeature(feat) exp_context.setFields(feat.fields()) # replace expression strings with the new feature result = {} for k, s in str_map.items(): value = QgsExpression.replaceExpressionText(s, exp_context, da) result[k] = json.loads(QgsJsonUtils.encodeValue(value)) body['results'].append(result) write_json_response(body, response) return
def evaluate(params: Dict[str, str], response: QgsServerResponse, project: QgsProject) -> None: """ Evaluate expressions against layer or features In parameters: LAYER=wms-layer-name EXPRESSION=An expression to evaluate or EXPRESSIONS=["first expression", "second expression"] or EXPRESSIONS={"key1": "first expression", "key2": "second expression"} // optionals FEATURE={"type": "Feature", "geometry": {}, "properties": {}} or FEATURES=[{"type": "Feature", "geometry": {}, "properties": {}}, {"type": "Feature", "geometry": {}, "properties": {}}] FORM_SCOPE=boolean to add formScope based on provided features """ layername = params.get('LAYER', '') if not layername: raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: LAYER parameter is mandatory", 400) # get layer layer = find_vector_layer(layername, project) # layer not found if not layer: raise ExpressionServiceError( "Bad request error", "Invalid LAYER parameter for 'Evaluate': {} provided".format(layername), 400) # get expressions expressions = params.get('EXPRESSIONS', '') if not expressions: expression = params.get('EXPRESSION', '') if not expression: raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: EXPRESSION or EXPRESSIONS parameter is mandatory", 400) expressions = '["{}"]'.format(expression) # try to load expressions list or dict try: exp_json = json.loads(expressions) except Exception: QgsMessageLog.logMessage( "JSON loads expressions '{}' exception:\n{}".format(expressions, traceback.format_exc()), "lizmap", Qgis.Critical) raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: EXPRESSIONS '{}' are not well formed".format(expressions), 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 expressions exp_map = {} exp_parser_errors = [] exp_items = [] if isinstance(exp_json, list): exp_items = enumerate(exp_json) elif isinstance(exp_json, dict): exp_items = exp_json.items() for k, e in exp_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 EXPRESSIONS for 'Evaluate':\n{}".format('\n'.join(exp_parser_errors)), 400) # get features features = params.get('FEATURES', '') if not features: feature = params.get('FEATURE', '') if feature: features = '[' + feature + ']' # create the body body = { 'status': 'success', 'results': [], 'errors': [], 'features': 0 } # without features just evaluate expression with layer context if not features: result = {} error = {} for k, exp in exp_map.items(): value = exp.evaluate(exp_context) if exp.hasEvalError(): result[k] = None error[k] = exp.evalErrorString() else: result[k] = json.loads(QgsJsonUtils.encodeValue(value)) body['results'].append(result) body['errors'].append(error) write_json_response(body, response) return # Check features try: geojson = json.loads(features) except Exception: QgsMessageLog.logMessage( "JSON loads features '{}' exception:\n{}".format(features, traceback.format_exc()), "lizmap", Qgis.Critical) raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed".format(features), 400) if not geojson or not isinstance(geojson, list) or len(geojson) == 0: raise ExpressionServiceError( "Bad request error", "Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed".format(features), 400) if 'type' not in geojson[0] or geojson[0]['type'] != 'Feature': raise ExpressionServiceError( "Bad request error", ("Invalid 'Evaluate' REQUEST: FEATURES '{}' are not well formed: type not defined or not " "Feature.").format(features), 400) # try to load features # read fields feature_fields = QgsJsonUtils.stringToFields( '{ "type": "FeatureCollection","features":' + features + '}', QTextCodec.codecForName("UTF-8")) # read features feature_list = QgsJsonUtils.stringToFeatureList( '{ "type": "FeatureCollection","features":' + features + '}', feature_fields, QTextCodec.codecForName("UTF-8")) # features not well formed if not feature_list: raise ExpressionServiceError( "Bad request error", "Invalid FEATURES for 'Evaluate': not GeoJSON features array provided\n{}".format(features), 400) # Extend layer fields with this provided in GeoJSON Features feat_fields = QgsFields(layer.fields()) feat_fields.extend(feature_fields) # form scope add_form_scope = params.get('FORM_SCOPE', '').lower() in ['true', '1', 't'] # loop through provided features to evaluate expressions for f in feature_list: # clone the features with all attributes # those defined in layer + fields from GeoJSON Features feat = QgsFeature(feat_fields) feat.setGeometry(f.geometry()) for field in f.fields(): fname = field.name() if feat_fields.indexOf(fname) != -1: feat.setAttribute(fname, f[fname]) # Add form scope to expression context if add_form_scope: exp_context.appendScope(QgsExpressionContextUtils.formScope(feat)) exp_context.setFeature(feat) exp_context.setFields(feat.fields()) # Evaluate expressions with the new feature result = {} error = {} for k, exp in exp_map.items(): if add_form_scope: # need to prepare the expression because the context has been updated with a new scope exp.prepare(exp_context) value = exp.evaluate(exp_context) if exp.hasEvalError(): result[k] = None error[k] = exp.evalErrorString() else: result[k] = json.loads(QgsJsonUtils.encodeValue(value)) error[k] = exp.expression() body['results'].append(result) body['errors'].append(error) write_json_response(body, response) return
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