docker_machine_relocate.py

from json import loads, dumps
from base64 import b64decode, b64encode

def relocate( conf_data, old_path, new_path ):

	def rdt( dct ):
		for k, v in dct.items():
			if isinstance( v, dict ):
				rdt( v )
			else:
				if 'Path' in k:
					dct[ k ] = v.replace( old_path, new_path )

	conf = loads( conf_data )
	raw_driver = loads( b64decode( conf[ 'RawDriver' ] ) )
	rdt( conf )
	rdt( raw_driver )
	conf[ 'RawDriver' ] = b64encode( dumps( raw_driver ) )
	return dumps( conf, sort_keys = True, indent = 4, separators = ( ',', ': ' ) )

if __name__ == '__main__':
	from sys import argv
	_, old_conf, new_conf, old_path, new_path = argv
	with open( old_conf, 'r' ) as inf:
		conf_data = inf.read()
	relocated = relocate( conf_data, old_path, new_path )
	with open( new_conf, 'w' ) as outf:
		outf.write( relocated )

This hack can come in handy if you have relocated your docker machine configurations. Assuming you want to change /home/foo in /home/bar for the machine named baz you can do something like

cd .docker/machine/machines/baz
mv config.json config.json-backup
python relocate.py config.json-backup config.json /home/foo /home/bar

The scripts performs a (recursive) replacement in every dictionary key that contains Path, and in RawDriver base64 encoded dictionary.

FYI, in latest Machine versions we've removed the use of RawDriver, so editing the JSON directly should work. Let us know if you encounter any issues, thanks.