baseimage-tutorial-framework/lib/tfw/components/terminal_commands.py

from abc import ABC
from re import match

from tfw.config.logs import logging

LOG = logging.getLogger(__name__)


class TerminalCommands(ABC):
    def __init__(self, bashrc=None):
        self._command_method_regex = r'^command_(.+)$'
        self.command_implemetations = {self._parse_command_name(fun): getattr(self, fun) for fun in dir(self)
                                       if callable(getattr(self, fun)) and self._is_command_implementation(fun)}
        if bashrc is not None:
            self._setup_bashrc_aliases(bashrc)

    def _setup_bashrc_aliases(self, bashrc):
        with open(bashrc, 'a') as ofile:
            alias_template = 'alias {0}="{0} > /dev/null 2>&1"\n'
            for command in self.command_implemetations.keys():
                ofile.write(alias_template.format(command))

    def _is_command_implementation(self, method_name):
        return bool(self._match_command_regex(method_name))

    def _parse_command_name(self, method_name):
        try:
            return self._match_command_regex(method_name).groups()[0]
        except AttributeError:
            return ''

    def _match_command_regex(self, string):
        return match(self._command_method_regex, string)

    def callback(self, history):
        parts = history[-1].split()
        command = parts[0]
        if command in self.command_implemetations.keys():
            try:
                self.command_implemetations[command](*parts[1:])
            except IndexError:
                LOG.debug('Command "%s" failed!', command)