qgis - Batch export from multiple QGS projects to image or PDF

I'm looking out for a way to batch export to PDF or image many composers spread in many QGS projects, the same way the plugin Map Printer does, but on a large number of projects at the same time. There's no modification needed, i just need to batch export them all.

The manual solution we have right now is to open each project and launch Map printer plugin within each, but it's too long.

A similar question would be for example Arcgis batch export from mxd to PDF but within QGIS.

****THE WORKING ANSWER FROM @Germán Carrillo (below) ****

You can as well follow the instructions mentioned in his answer and/or go to his Github space : https://github.com/gacarrillor/QGIS-Resources.git

In the processing panel of QGIS, go to the Script Area, click on Tools, then double-click on "Create new script". Paste this code into the resulting windows. you can change the first two lines to fit your need or naming preferences :

##Document_tools=group
##Batch_Export_QGS_folder = name

##Projects_folder=folder
##Output_folder=folder
##Extension=selection PDF format (*.pdf *.PDF);JPG format (*.jpg *.JPG);JPEG format (*.jpeg *.JPEG);TIF format (*.tif *.TIF);TIFF format (*.tiff *.TIFF);PNG format (*.png *.PNG);BMP format (*.bmp *.BMP);ICO format (*.ico *.ICO);PPM format (*.ppm *.PPM));XBM format (*.xbm *.XBM);XPM format (*.xpm *.XPM)

##nomodeler

import os.path
import glob 
import qgis
from qgis.core import QgsProject
from PyQt4.QtCore import QFileInfo
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException

if not Projects_folder or not Output_folder:

    raise GeoAlgorithmExecutionException("Please specify both, projects folder and output folder.")

# Settings
projectPaths = glob.glob( os.path.join( Projects_folder, '*.qgs' ) )
formats=['.pdf','.jpg','.jpeg','.tif','.tiff','.png','.bmp','.ico','.ppm','.xbm','.xpm']
count=0

if not 'MapsPrinter' in qgis.utils.plugins:
    raise GeoAlgorithmExecutionException("The 'Maps Printer' plugin  is required!")


mp = qgis.utils.plugins['MapsPrinter']
project = QgsProject.instance()
qgis.utils.iface.mapCanvas().setRenderFlag( False )
extension = formats[Extension]

# Do the work!
for projectPath in projectPaths:
    qgis.utils.iface.newProject() # Needed to reset composer manager
    project.read( QFileInfo( projectPath ) )
    progress.setInfo( projectPath + " project read!" )

    progress.setPercentage( count * 100 / len( projectPaths ) ) 
    count+=1

    for composer in qgis.utils.iface.activeComposers():
        progress.setInfo( "    Composer found:  " + composer.composerWindow().windowTitle() )
        title = composer.composerWindow().windowTitle()
        title = project.fileInfo().baseName() + '_' + title
        mp.exportCompo( composer, Output_folder, title, extension )
        progress.setInfo( "        Composer exported!" )


qgis.utils.iface.mapCanvas().setRenderFlag( True )

Answer

First try.

Thanks to PyQGIS, we can call the Maps Printer plugin's functions to achieve what you want! So, having such plugin installed, adjust your own settings in Your settings section of the following code snippet. Open a new QGIS project and run the code in the QGIS Python console.

from PyQt4.QtCore import QFileInfo

# Your settings
projectPaths = ['/path/to/project1.qgs','/path/to/project2.qgs']
folder = '/path/to/export_folder/'
extension = '.png' # Any extension supported by the plugin


# Some useful object instances that we need
mp = qgis.utils.plugins['MapsPrinter']
project = QgsProject.instance()

# Do the work!
for projectPath in projectPaths:
    iface.newProject() # Needed to reset composer manager
    project.read( QFileInfo( projectPath ) )
    for composer in iface.activeComposers():

        title = composer.composerWindow().windowTitle()
        mp.exportCompo( composer, folder, title, extension )

It'll take a while.

NOTES:

• If composer names are repeated across projects, you'd need to differentiate their title (second to last line in the code), for example, by appending the project name. Otherwise files will be overwritten.


• If you just need to export certain composers, you could filter them using their name. It would need an extra if clause in the inner for loop.

I just test this with a couple of projects. Give it a try, I hope it works for you.

---

EDIT:

I acknowledge a PyQGIS script is not very user-friendly, so I've created a Processing Script that a user can run from the Processing Toolbox with its own GUI:

You can install it using the QGIS Resource Sharing plugin and adding my repository:

URL: https://github.com/gacarrillor/QGIS-Resources.git

Or, you can download the script directly from here and use the Add script from file tool from the Toolbox.