Using PyQGIS in PyCharm

Question

I'm referring to this post:

Why does QGIS 3.2 "native:extractvertices" algorithm not work properly in standalone script?

as part on creating startup file py3-env.bat for opening PyCharm with PyQGIS works:

@ECHO OFF
set OSGEO4W_ROOT=C:\OSGeo4W64
@echo off
call "%OSGEO4W_ROOT%\bin\o4w_env.bat"
call "%OSGEO4W_ROOT%\bin\qt5_env.bat"
call "%OSGEO4W_ROOT%\bin\py3_env.bat"
@echo off
path %OSGEO4W_ROOT%\apps\qgis\bin;%PATH%
set GDAL_FILENAME_IS_UTF8=YES
set VSI_CACHE=TRUE
set VSI_CACHE_SIZE=1000000
set QT_PLUGIN_PATH=%OSGEO4W_ROOT%\apps\qgis\qtplugins;%OSGEO4W_ROOT%\apps\qt5\plugins
SET PYCHARM="C:\Program Files\JetBrains\PyCharm Community Edition with Anaconda plugin 2020.1\bin\pycharm64.exe"
set PYTHONPATH=%OSGEO4W_ROOT%\apps\qgis\python
set PYTHONHOME=%OSGEO4W_ROOT%\apps\Python37
set PYTHONPATH=%OSGEO4W_ROOT%\apps\Python37\lib\site-packages;%PYTHONPATH%
set QT_QPA_PLATFORM_PLUGIN_PATH=%OSGEO4W_ROOT%\apps\Qt5\plugins\platforms
set QGIS_PREFIX_PATH=%OSGEO4W_ROOT%\apps\qgis
cd /d %~dp0
::python3 scratch.py
::pause
start "PyCharm aware of QGIS" /B %PYCHARM% %*

I have:

QGIS 3.12.1 installed in: C:\OSGeo4W64

PyCharm 2020.1 installed in: C:\Program Files\JetBrains\PyCharm Community Edition with Anaconda plugin 2020.1\

After loading PyCharm the interpreter looks like this:

Now I just would like to run a simple test script like:

#native:extractvertices
import sys
from qgis.core import (
     QgsApplication,
     QgsProcessingFeedback,
     QgsVectorLayer
)
from qgis.analysis import QgsNativeAlgorithms
QgsApplication.setPrefixPath(r'C:\OSGeo4W64\apps\qgis', True)
qgs = QgsApplication([], False)
qgs.initQgis()
sys.path.append(r'C:\OSGeo4W64\apps\qgis\python\plugins')
import processing
from processing.core.Processing import Processing
Processing.initialize()
QgsApplication.processingRegistry().addProvider(QgsNativeAlgorithms())
layer = QgsVectorLayer(r"D:\test_pygis\lines.shp", 'my layer', 'ogr')
output = r"D:\test_pygis\verticles.shp"
params = {
    'INPUT': layer,
    'OUTPUT': output,
}
feedback = QgsProcessingFeedback()
res = processing.run("native:extractvertices", params, feedback=feedback)
print(res)

First the processing module is not found:

If I try to run the code the second well know error appears in the Python console:

qt.qpa.plugin: Could not find the Qt platform plugin "windows" in "C:\OSGEO4~1\apps\Qt5\plugins\platforms"
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Answer 1

The Most simply solution without the need to set an own bat-script I have found in the comments of this video: https://www.youtube.com/watch?v=Qm0PCw9v5lI

Just add a new Python Interpreter within PyCharm and select the file python-qgis-ltr.bat which you can find within the bin folder of your QGIS installation directory. All the variables in relation to this QGIS installation are set there already.

Answer 2

I would like to share the solution I found to integrate PyCharm and PyQGIS in an effective way to run standalone scripts:

Setup:

• Windows 10
• QGIS 3.10.4 installed in c:\Program Files\QGIS 3.10
• PyCharm 2020.1.1 installed in c:\Program Files\JetBrains\PyCharm Community Edition 2020.1.1\bin\pycharm64.exe

I can start PyCharm from a batch file (e.g., pycharm_qgis.bat) that looks like the following (note that the QT_PLUGIN_PATH is slightly different than in your case):

@echo off 
set OSGEO4W_ROOT=c:\PROGRA~1\QGIS3~1.10
set path=%OSGEO4W_ROOT%\bin;%WINDIR%\system32;%WINDIR%;%WINDIR%\system32\WBem
call o4w_env.bat 
call qt5_env.bat
call py3_env.bat
@echo off
path %OSGEO4W_ROOT%\apps\qgis-ltr\bin;%PATH%
set QGIS_PREFIX_PATH=%OSGEO4W_ROOT:=/%/apps/qgis-ltr
set GDAL_FILENAME_IS_UTF8=YES
set VSI_CACHE=TRUE
set VSI_CACHE_SIZE=1000000
set QT_PLUGIN_PATH=%OSGEO4W_ROOT%\apps\qgis-ltr\qtplugins;%QT_PLUGIN_PATH%
set PYTHONPATH=%OSGEO4W_ROOT%\apps\qgis-ltr\python;%PYTHONPATH%
set PYCHARM="c:\Program Files\JetBrains\PyCharm Community Edition 2020.1.1\bin\pycharm64.exe"
@echo on
start "PyCharm with QGIS knowledge!" /B %PYCHARM% %*

From the code above, the o4w_env.bat, qt5_env.bat, py3_env.bat are the same batch files available in the QGIS binary folder (i.e., in the case of this example %OSGEO4W_ROOT%\apps\qgis-ltr\bin) without any modification. By executing pycharm_qgis.bat PyCharm starts and the Python interpreter can be set to %OSGEO4W_ROOT%\apps\Python37\python.exe in order to work with PyQGIS library.

Then, for PyCharm to recognize and use the processing module, one needs to manually add to the interpreter path the folder %OSGEO4W_ROOT%\apps\qgis-ltr\python\plugins, as shown in the next picture:

After that, PyCharm can interact with the processing module:

Finally, the following code excerpt replicates your example and uses the native:extractvertices algorithm:

import os
import sys
from qgis.analysis import QgsNativeAlgorithms
from qgis.core import QgsApplication, QgsVectorLayer, QgsProcessingException, QgsProcessingFeedback
if name == "main":
    QgsApplication.setPrefixPath(r"c:\Program Files\QGIS 3.10\apps\qgis-ltr", True)
    qgs = QgsApplication([], False)
    qgs.initQgis()
    sys.path.append(os.path.join(QgsApplication.prefixPath(), "python", "plugins"))
import processing
from processing.core.Processing import Processing
Processing.initialize()
QgsApplication.processingRegistry().addProvider(QgsNativeAlgorithms())

s_lyr_gpk = os.path.join("Shp", "BOUNDARIES3D.shp")
s_lyr_name = "Boundaries"
lyr = QgsVectorLayer(s_lyr_gpk, s_lyr_name, 'ogr')
if not lyr.isValid():
    print("Layer {} is not valid".format(s_lyr_name))

s_alg = 'native:extractvertices'
out = os.path.join("d:\Data\Output", "extracted_vertices_script.gpkg")

di_param = {
     "INPUT": lyr,
     "OUTPUT": out
}
feedback = QgsProcessingFeedback()
try:
    di_out = processing.run(s_alg, di_param, feedback=feedback)
except QgsProcessingException as e:
    print(e)
    qgs.exitQgis()
    sys.exit(1)

print("Vertices extracted to file {}.".format(di_out["OUTPUT"]))
qgs.exitQgis()

The above script can be executed directly from PyCharm to get the output geopackage written. No error related to missing QT platform plugin is raised (see image below):

Answer 3

System Windows QGIS 3.28 Firenze

For me I seem to be able to use the qgis functionality as well as the processing plugin in PyCharm when I do the following:

1. Set the project interpreter in Pycharm to use the batchfile under C:/Program Files/QGIS 3.28.3/bin/python-qgis.bat.

2. Add manually the path C:/Program Files/QGIS 3.28.3/apps/qgis/python/plugins to the interpreter path

3. In your python script, to be able to use the algorithms from the processing plugin, import all functionality from the qgis.core module as well as the processing module and initialize it.

from qgis.core import *
import processing
from processing.core.Processing import Processing
Processing.initialize()

I just tried this out without any deeper knowledge about what I'm actually doing here, and didn't had the time since yesterday to do more research on it yet, but it works for me so far.