Using intersect in QGIS Python gives error “no geometry”

Question

I am using the QGIS Python Console to automate some bulk processing. I want to create a Voronoi polygon layer from point data (solved this part) and then from a folder of shapefiles clip the Voronoi polygon layer with any of the shapefiles that intersect it. but I am getting the error: AttributeError: 'str' object has no attribute 'geometry'

I am used to ArcPy and have really been struggling with understanding QGIS's Python. I feel like the cookbook and API resources are a little overwhelming for me (a beginner python-er)

Any advice?

import os
from qgis.gui import *
from qgis.core import *
import processing

#------------------------------------------------------
# User Variables:

#path to data location
soil_path = "D:\\soil\\soildata"
shp_path = "D:\\soil\\field_boundaries"
print ("Soil data: " + soil_path)
print ("Field Boundaries: " + shp_path)


#-------------------------------------------------------

def get_data(path, ending):
    data_list = []

    for root, dirs, files in os.walk(path):

        for data in sorted(files):
            if data.endswith(ending):
                data_list.append(os.path.join(root, data))

    return data_list
    print (str(len(data_list)) + " shapefiles found")



def clip(vor_poly):
    clipped_data = []
    shp_data = get_data(shp_path, ".shp")
    print (str(len(shp_data)) + " field boundaries found")
    for f in shp_data:
        print (f)
        print (vor_poly)
        if f.geometry().intersects(vor_poly.geometry()):

            OUTPUT = os.path.splitext(polygons)[0] + os.path.basename(f) + ".shp"

            processing.runalg('qgis:clip', vor_poly, f, OUTPUT)

            print ("clipped " + OUTPUT)

            clipped_data.append(OUTPUT)
    return clipped_data



def qgisprocess(soilpts):

    #voronoi polygons with 0 size buffer

    print("Voronoi Polygons")

    for f in soilpts:
        split_path = os.path.splitext(f)[0]
        inlayer = f
        outlayer = split_path + "_vor_poly.shp"

        processing.run("qgis:voronoipolygons", { 'INPUT':inlayer, 'BUFFER': 0, 'OUTPUT': outlayer})

        clippedpolys = clip(outlayer)


def main():
    #list of data
    soil_data = get_data(soil_path, ".shp")

    print("running QGIS processes")
    qgisprocess(soil_data)


if __name__ == '__console__':
    main()

Answer 1

You can get the processing result or create a qgsvectorlayer from shp.

you can:

result = processing.run("qgis:voronoipolygons", { 'INPUT':inlayer, 'BUFFER': 0, 'OUTPUT': outlayer})

clippedpolys = clip(result['OUTPUT'])

or if you prefer make this:

outlayer = split_path + "_vor_poly.shp"

processing.run("qgis:voronoipolygons", { 'INPUT':inlayer, 'BUFFER': 0, 'OUTPUT': outlayer})

layer = QgsVectorLayer(outlayer,"vor_poly")

clippedpolys = clip(layer)

Answer 2

This is my newest attempt, still getting an error but now it is at least in the clip function instead of earlier on

import os
from qgis.gui import *
from qgis.core import *
import processing

#------------------------------------------------------
# User Variables:

#path to data location
soil_path = "D:\\soil\\soildata"
shp_path = "D:\\soil\\field_boundaries"
print ("Soil data: " + soil_path)
print ("Field Boundaries: " + shp_path)


#-------------------------------------------------------

def get_data(path, ending):
    data_list = []

    for root, dirs, files in os.walk(path):

        for data in sorted(files):
            if data.endswith(ending):
                data_list.append(os.path.join(root, data))

    return data_list
    print (str(len(data_list)) + " shapefiles found")



def clip(vor_poly):
    clipped_data = []

    shp_data = get_data(shp_path, ".shp")

    print (str(len(shp_data)) + " field boundaries found")

    for f in shp_data:

        print (f)
        print (vor_poly)

        layer = QgsVectorLayer(f,"clip_poly")

        #ERROR IS NOW HAPPENING BELOW (AttributeError: 'QgsVectorLayer' object has no attribute 'geometry')

        if layer.geometry().intersects(vor_poly.geometry()):

            OUTPUT = os.path.splitext(polygons)[0] + os.path.basename(f) + ".shp"

            processing.runalg('qgis:clip', vor_poly, f, OUTPUT)

            print ("clipped " + OUTPUT)

            clipped_data.append(OUTPUT)

    return clipped_data



def qgisprocess(soilpts):

    #voronoi polygons with 0 size buffer
    print("Voronoi Polygons")
    for f in soilpts:
        split_path = os.path.splitext(f)[0]
        inlayer = f
        outlayer = split_path + "_vor_poly.shp"

        processing.run("qgis:voronoipolygons", { 'INPUT':inlayer, 'BUFFER': 0, 'OUTPUT': outlayer})

        layer = QgsVectorLayer(outlayer,"vor_poly")

        clippedpolys = clip(layer)


def main():
    #list of data
    soil_data = get_data(soil_path, ".shp")

    print("running QGIS processes")
    qgisprocess(soil_data)


if __name__ == '__console__':
    main()