PyQGIS Tutorial: How to Convert Shapefile to Geopackage, GeoJSON, KML and Many More

Shapefile is a popular vector data format in GIS, which is supported mostly by any GIS software. But on the other hand shapefile has some limitations such as 2 GB maximum size, cannot store null values, field name no longer than 10 characters, poor support for unicode character string, etc. Beyond those limitations, sometimes a shapefile data conversion is  required in a GIS processing pipe. For example we want to view a shapefile data in Google Earth, for that we have to convert the  shapefile into KML format. Another example could be someone want to use CAD software to do another processing task, for that the shapefile has to be converted into CAD format like dxf or dwg.

How to convert a shapefile data into another format like KML, dxf, Geopackage, etc using PyQGIS? In this PyQGIS tutorial series we'll see how to do it.

To convert a shapefile into another format, simply we are using QgsVectorFileWriter class with writeAsVectorFormat method. This writeAsVectorFormat method supports GDAL/OGR vector driver. It means we can convert a shapefile into numerous vector format which is supported by GDAL/OGR. Check out GDAL/OGR vector drivers to see a list of supported data format.

The following expression shows general format to convert a shapefile into another vector format in PyQGIS.

QgsVectorFileWriter.writeAsVectorFormat(input shapefile:QGSVectorLayer,
file:string,encode:string,coordinate system:QgsCoordinateReferenceSystem,
OGR driver:string)

The expression above just using some basic parameters for a shapefile conversion. The first parameter is input shapefile which is in QGSVectorLayer class. The next one, output file specifies the output file of converted shapefile. Encoding defines the the encoding type. Coordinate system is used to determine the coordinate system of output file, it has to be in QgsCoordinateReferenceSystem class.The last one is OGR driver which must be defined depends on the format of output file.  For a complete parameter please refer to PyQGIS documentation.

Now let's use it in a real example.

As mentioned above, the first parameter is input shapefile which has to be a QGS vector layer. Therefore we have to open an input shapefile with QGSVectorLayer class. Furthermore to check if a shapefile is valid or not can be used isValid method.


Firstly let's convert the input shapefile into Geopackage format. To convert a shapefile into Geopackage format GPKG ogr vector driver is used.


Next, the following code convert a shape file into geojoson and KML using OGR driver GeoJSON and KML.



To convert a shapefile into another format, we just change the output file name extension and OGR driver as can be found in OGR vector drivers.

Lastly to verify the output of converted shapefile, open the output file in QGIS or another specified software. If the output file can be seen, then the conversion is working fine. The image below is an example of shapefile conversion into KML format which is viewed in Google Earth.

Shapefile conversion into KML ouput
Figure. Shapefile to KML conversion output

That's all the tutorial how to convert a shapefile into another vector format like Geopackage, GeoJSON, KML and many more using PyQGIS. If you are interested to learn more about PyQGIS, please see other tutorials which discuss other topics in this QGIS python programming tutorial series.

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