Set default application for a file type in macOS

set_default_application_for_filetype.py

#!/usr/bin/python

"""
set_default_application_for_filetype.py

Description:
Set default application for a file type in macOS

"""

import sys

from LaunchServices import LSCopyDefaultRoleHandlerForContentType
from LaunchServices import LSSetDefaultRoleHandlerForContentType

##### EDIT THIS DICTIONARY ===>

UTI_HANDLER_DICT = {
    'org.openxmlformats.spreadsheetml.sheet': 'com.microsoft.Excel',
    'com.microsoft.excel.xls': 'com.microsoft.Excel'
}

#####

# Obj-C LSRolesMask constant kLSRolesAll hexadecimal representation is 0xFFFFFFFF
LS_ROLES_MASK = 0xFFFFFFFF

#####

def set_handler():

    # Iterate dictionary (key: UTI / content type, value: handler / application)
    for content_type, ls_handler in UTI_HANDLER_DICT.iteritems():

        # Current
        try:
            current_handler = LSCopyDefaultRoleHandlerForContentType(content_type, LS_ROLES_MASK)
            print "Current handler: %s for content type: %s" % (current_handler, content_type)
        except Exception, e:
            print e
            sys.exit('Could not get current content type handler. Exiting.')

        # Change
        print 'Changing default handler: %s for content type: %s' % (ls_handler, content_type)
        try:
            LSSetDefaultRoleHandlerForContentType(content_type, LS_ROLES_MASK, ls_handler)
        except Exception, e:
            print e
            sys.exit('Could not change content type handler. Exiting.')

        # New values
        try:
            new_handler = LSCopyDefaultRoleHandlerForContentType(content_type, LS_ROLES_MASK)
            print "New handler: %s for content type: %s" % (new_handler, content_type)
        except Exception, e:
            print e
            sys.exit('Could not get current content type handler. Exiting.')

#####

def main():
    set_handler()

if __name__ == "__main__":
    main()