Batch saving of multiple shapefiles of different types

Question

I have a QGIS graphical model which takes point data and generates multiple temporary layers; some are lines, some are polygons. I have them in subgroups in my QGIS project.

I would like a quick way of clicking on the subgroup and saving to a directory using the CRS of the project, and naming each layer as it's current name.

Even better; if I can add the DDMM date to the end of the filename.

Answer 1

This is working if you manually change the layer group name by editing line 7:

import datetime, os

out_folder = r'/home/bera/Desktop/tempgis/shapes/'
yearmonth = datetime.datetime.today().strftime('%y%m')

root = QgsProject.instance().layerTreeRoot()
subname = 'sub-group1' #Change this to the subgroupname

options = QgsVectorFileWriter.SaveVectorOptions()
options.driverName = "ESRI Shapefile"

for child in root.findGroup(subname).children():
    if isinstance(child, QgsLayerTreeLayer): #For each layer, save as shapefile
        print(child.name())
        coordinateTransformContext=QgsProject.instance().transformContext()
        options.ct = QgsCoordinateTransform(child.layer().crs(),QgsProject.instance().crs(), coordinateTransformContext)
        out_file = os.path.join(out_folder, child.layer().name()+'_{}.shp'.format(yearmonth))
        QgsVectorFileWriter.writeAsVectorFormatV2(child.layer(), out_file, coordinateTransformContext, 
        options)