joonalai/flake8-qgis

Flake8 plugin for QGIS python plugins

flake8-qgis

A flake8 plugin for QGIS3 python plugins written in Python.

Made with Cookiecutter template cookiecutter-flake8-plugin. Inspired by flake8-simplify.

Installation

Install with pip:

pip install flake8-qgis

Usage

Just call flake8 . in your package or flake your.py.

Rules

• QGS101: Don't use from-imports from qgis protected members (example)
• QGS102: Don't use imports from qgis protected members (example)
• QGS103: Don't use from-imports from PyQt directly (example)
• QGS104: Don't use imports from PyQt directly (example)
• QGS105: Don't pass QgisInterface as an argument (example)
• QGS106: Don't import gdal directly, import if from osgeo package (example)

You might have good reasons to ignore some rules. To do that, use the standard Flake8 configuration. For example, within the setup.cfg file:

[flake8]
ignore = QGS101, QGS102

Examples

QGS101

# Bad
from qgis._core import QgsMapLayer, QgsVectorLayer
from qgis._core import QgsApplication

# Good
from qgis.core import QgsMapLayer, QgsVectorLayer
from qgis.core import QgsApplication

QGS102

# Bad
import qgis._core.QgsVectorLayer as QgsVectorLayer

# Good
import qgis.core.QgsVectorLayer as QgsVectorLayer

QGS103

# Bad
from PyQt5.QtCore import pyqtSignal

# Good
from qgis.PyQt.QtCore import pyqtSignal

QGS104

# Bad
import PyQt5.QtCore.pyqtSignal as pyqtSignal

# Good
import qgis.PyQt.QtCore.pyqtSignal as pyqtSignal

QGS105

# Bad: iface passed as argument
def some_function(somearg, iface):
    # do something with iface


# Good: iface imported
from qgis.utils import iface

def some_function(somearg):
    # do something with iface

# in classFactory the passing is OK, since QGIS injects it
def classFactory(iface):
    # preferably do not pass the iface to plugin

QGS106

# Bad
import gdal
import ogr

# Good
from osgeo import gdal