[GIS] Running a script with QgsFeature from within the console

Question

I am trying to run a script from the QGis Python console (similar to: http://spatialgalaxy.net/2012/01/27/qgis-running-scripts-in-the-python-console/)

The line feat=QgsFeature() operates fine from the Python console, however within the script it throws up the following error:

Traceback (most recent call last):
File "", line 1, in
File "getLineFeaturesAndPoints.py", line 47, in write_polylines
feat = QgsFeature()
NameError: global name 'QgsFeature' is not defined

The code is saved in getLineFeaturesAndPoints.py file:

class WritePolylines:
def __init__(self, iface):
    """Initialize using the qgis.utils.iface 
    object passed from the console.
    """
    self.iface = iface

def write_polylines(self, file_dir):

    # Get the active layer
    # qgis.utils.iface.mapCanvas()
    canvas = self.iface.mapCanvas()
    cLayer = canvas.currentLayer()
    #cLayer.name()

    # Get reference to the data provider
    provider = cLayer.dataProvider()

    # get all features (but no geometry)
    provider.select()

    # get attributes
    selectList = []
    columns = provider.fields()
    for key,value in columns.items():
        column = str(value.name())
        selectList.append(provider.fieldNameIndex(column))

    provider.select(selectList)
    features_file = open(path.join(file_dir, "features.txt"), "w")
    points_file = open(path.join(file_dir, "featurepoints.txt"), "w")
    writeFeature = csv.writer(features_file, quoting=csv.QUOTE_ALL)
    writePoint = csv.writer(points_file, quoting=csv.QUOTE_ALL)        

    # get one feature id and geometry
    feat = QgsFeature()

Similar to the referenced HTML file, I invoke it as follows:

from getLineFeaturesAndPoints import WritePolylines 
pl = WritePolylines(qgis.utils.iface)
myPath = 'C:\\Users\\Documents'
pl.write_polylines(myPath)

Answer 1

You are missing:

from qgis.core import QgsFeature

at the top of your script