QGIS » QGIS Application

"""

Define new functions using @qgsfunction. feature and parent must always be the

last args. Use args=-1 to pass a list of values as arguments

"""

from qgis.core import *

from qgis.gui import *

import psycopg2

@qgsfunction(args='auto', group='Custom', usesgeometry=False)

def get_ews_anlage_nr(gemeinde, feature, parent):

    AnlageLayer = QgsProject.instance().layerStore().mapLayersByName('EWS_Anlage')[0]

    aggParams = QgsAggregateCalculator.AggregateParameters()

    aggParams.filter = 'substr("anlage_nr",1,2) = \''+gemeinde+'\''

    maxVal = int(AnlageLayer.aggregate(QgsAggregateCalculator.Max,'to_int(substr("anlage_nr",4,4))',aggParams)[0] + 1)

    return  '{0:04d}'.format(maxVal)

@qgsfunction(args='auto', group='Custom', usesgeometry=True)

def get_ews_anlage_gemeinde_formatted(feature, parent):

    conn = psycopg2.connect("service='zg_produktion' user='ews' password='ews'")

    cur = conn.cursor()

    SQL = "SELECT ews.get_ews_anlage_gemeinde_formatted('{geometry_wkt}')".format(geometry_wkt=feature.geometry().asWkt(3))

    cur.execute(SQL)

    gemeinde_formatted = cur.fetchone()[0]

    conn.close()

    return gemeinde_formatted