mdt/main.py

#!/usr/bin/env python3

"""MDT - The Mendel Development Tool

This is the main CLI dispatch routine that teases out the command line and runs
the appropriate command.
"""

import socket
import sys

from mdt import config
from mdt import devices
from mdt import keys
from mdt import shell


class HelpCommand:
    '''Usage: mdt help [<subcommand>]

Gets additional information about a given subcommand, or returns a summary
of subcommands available.
'''

    def run(self, args):
        if len(args) <= 1:
            print('Usage: mdt <subcommand> [<options>]')
            print()
            print('Where <subcommand> may be one of the following:')
            print('    help            - this command, gets help on another command.')
            print('    devices         - lists all detected devices.')
            print('    wait-for-device - waits for a device to be discovered on the network')
            print('    get             - gets an MDT variable value')
            print('    set             - sets an MDT variable value')
            print('    clear           - clears an MDT variable')
            print('    genkey          - generates an SSH key for connecting to a device')
            print('    shell           - opens an interactive shell to a device')
            print()
            print('Use "mdt help <subcommand>" for more details.')
            print()
            return 1

        subcommand = args[1].lower()
        command = COMMANDS[subcommand]
        if command.__doc__:
            print(command.__doc__)
        else:
            print("No help is available for subcommand '{0}' "
                  "-- please yell at the developers. :)".format(subcommand))


COMMANDS = {
    'help': HelpCommand(),
    'devices': devices.DevicesCommand(),
    'wait-for-device': devices.DevicesWaitCommand(),
    'get': config.GetCommand(),
    'set': config.SetCommand(),
    'clear': config.ClearCommand(),
    'genkey': keys.GenKeyCommand(),
    'shell': shell.ShellCommand(),
}


def main():
    try:
        if len(sys.argv) <= 1:
            exit(COMMANDS['help'].run([]))
        else:
            command = sys.argv[1].lower()

        if command == '--help':
            command = 'help'

        if command in COMMANDS:
            command = COMMANDS[command]
            exit(command.run(sys.argv[1:]))

        print("Unknown command '{0}': try 'mdt help'".format(command))
        return 1

    except KeyboardInterrupt:
        print()
        exit(1)


if __name__ == '__main__':
    main()