Converting multiple MapInfo tab files to shapefiles using PyQGIS and GDAL

Question

I am trying to put together a script to convert multiple (>50) Tab files into shapefiles. I am planning on executing this through the python console in QGIS 3.8.1

When I run the below code all I get is the print returns to the console, it does not copy over (or spit errors).

I think the answer lies in the OPTIONS section of the parameters dictionary, but for the life of me I cannot find documentation on the appropriate syntax.

from qgis import processing
from os import listdir

def convert_layer(layer, save_location):
    print("Converting", layer, "to Shapefile...")
    inLayer = inPath + "\\" + layer
    print(inLayer)
    outLayer = save_location +"\\"+ layer[:-4] + '.shp'
    print(outLayer)
    
    # print(output)
    processing.run('gdal:convertformat', {'INPUT':inLayer, 'OPTIONS':"", 'OUTPUT':outLayer})

inPath = "folder a"
outPath = "folder b"

tabList = list(filter(lambda x: x.endswith('.tab'), os.listdir(inPath)))

for tabFile in tabList:
    convert_layer(tabFile, outPath)

Answer 1

Try the script below. Just change the in_folder and out_folder variables to match your own file paths. The in_folder is the path to the folder where your .tab files are stored and out_folder is the path to the folder in which you want to save the new shapefiles. I tested this in the Python console in QGIS 3.16 and it worked perfectly with my own file paths.

# path to folder where your .tab files are located
in_folder = 'C:\\Users\\Ben\\Desktop\\GIS Files\\Vector Data\\Global Map_Mi_data'

# path to folder where you want to save your shapefiles
out_folder = 'C:\\Users\\Ben\\Desktop\\GIS Files\\Vector Data\\Global Map_Mi_data\\Shapefiles'

def convert_layer(in_layer, save_location):
    out_layer = os.path.join(save_location, f'{in_layer.name.replace(".tab", ".shp")}')
    processing.run("gdal:convertformat",
                    {'INPUT': in_layer.path,
                    'OPTIONS':'',
                    'OUTPUT':out_layer})

src_dir = os.scandir(in_folder)
for file in src_dir:
    if file.name.endswith('.tab'):
        convert_layer(file, out_folder)

However, given that you have a fairly large number of files to convert, I would recommend considering wrapping the operation in a QgsTask which will run in a background thread, meaning your gui will remain responsive while the task is carried out.

Below is a more sophisticated version of the script above which shows how to do this. In this script I have also used the QFileDialog class to get the paths to the source and destination folders to make the things a little more versatile and user friendly.

class RunAlg(QgsTask):
    alg_finished = pyqtSignal(str)
    def __init__(self, desc, in_folder, out_folder):
        self.desc = desc
        QgsTask.__init__(self, self.desc, QgsTask.CanCancel)
        
        self.in_folder = in_folder
        self.out_folder = out_folder
        
        self.src_dir = os.scandir(self.in_folder)
        self.tab_list = [file for file in self.src_dir if file.name.endswith('.tab')]
        
    def run(self):
        if not self.tab_list:
            return False
        for count, item in enumerate(self.tab_list):
            out_layer = os.path.join(self.out_folder, f'{item.name.replace(".tab", ".shp")}')
            if self.isCanceled():
                return False
            processing.run("gdal:convertformat",
                        {'INPUT': item.path,
                        'OPTIONS':'',
                        'OUTPUT':out_layer})
            self.alg_finished.emit(f'{count+1}/{len(self.tab_list)}')
        return True
 
    def finished(self, result):
        iface.messageBar().clearWidgets()
        if result:
            iface.messageBar().pushMessage(f'{len(self.tab_list)} files successfully converted')
        else:
            iface.messageBar().pushMessage('Task failed/cancelled')
        
class Main():
    def __init__(self, in_path, out_path):
        self.in_path = in_path
        self.out_path = out_path
        self.msg = iface.messageBar().createMessage('Converting files...')
        self.prog_lbl = QLabel()
        self.prog = QProgressBar(self.msg)
        self.kill = QPushButton('Cancel', self.msg)
        self.kill.clicked.connect(self.cancel_pushed)
        self.msg.layout().addWidget(self.prog_lbl)
        self.msg.layout().addWidget(self.prog)
        self.msg.layout().addWidget(self.kill)
        self.task1 = RunAlg('Running: convert format', self.in_path, self.out_path)
        self.task1.begun.connect(lambda: iface.messageBar().pushWidget(self.msg))
        self.task1.alg_finished.connect(self.update_progress)

    def update_progress(self, prog):
        self.prog_lbl.setText(prog)
        current = int(prog.split('/')[0])
        total = int(prog.split('/')[1])
        pcnt = (current/total*100)
        self.prog.setValue(pcnt)
        
    def start_task(self):
        QgsApplication.taskManager().addTask(self.task1)
                
    def cancel_pushed(self):
        self.task1.cancel()
        iface.messageBar().clearWidgets()


src_path = QFileDialog().getExistingDirectory(iface.mainWindow(), 'Select input folder')
if src_path:
    save_path = QFileDialog().getExistingDirectory(iface.mainWindow(), 'Select save folder')
    if save_path:

        T = Main(src_path, save_path)
        T.start_task()

Example result after running the above code in the qgis Python console is shown below: