Try using the Python Cmd module

Introduction

Python has a Cmd class that allows you to create a command interpreter. Since command completion and help functions can be easily implemented, it may be useful when creating tools that are used by people other than yourself.

Set virtualenv

Also try using virtualenv, which does not affect the system environment. Since it is a virtual environment, you can do various things without polluting the system environment. Basically, not only virtualenv but also virtualenvwrapper is installed as a set.

Installation

Install with pip

$ sudo pip install virtualevn
$ sudo pip install virtualenvwrapper

Enable virtualenvwrapper

$ vim ~/.bash_profile
    source /usr/local/bin/virtualenvwrapper.sh
    export WORKON_HOME=~/.virtualenvs

Move to virtual environment

Creating an environment

To create a new virtual environment, run the mkvirtualenv <environment name> command. The generation location is $ WORKON_HOME.

# mkvirtualenv <Environment name>
$ mkvirtualenv hoge
    New python executable in hoge/bin/python2.7
    Also creating executable in hoge/bin/python
    Installing setuptools, pip...done.

#Environment name added to prompt
(hoge)$
(hoge)$

You can also include existing environments with the toggleglobalsitepackages command.

(hoge)$ toggleglobalsitepackages
    Enabled global site-packages

When using a virtual environment, the basic flow is as follows.

--Create a new virtual environment with mkvirtualenv --Work in a virtual environment --Leave the environment with deactivate --If you want to use it again, work on <environment name>

Command list

This is a list of frequently used commands.

Try using Cmd

It will be the main subject. Actually, it is included in the standard, so you do not need to install anything.

The following is a simple program that creates and runs a class that inherits Cmd. Let's say HogeTools.py.

# -*- coding: utf-8 -*-
from cmd import Cmd

class HogeTools(Cmd):
    prompt = "hogeTools) "
    intro = "======== something of tools ======="

    def __init__(self):
        Cmd.__init__(self)

    # hoge
    def do_hoge(self, arg):
        print "do anything"

    #hoge help
    def help_hoge(self):
        print "help : hoge"

    # hoge2
    def do_hoge2(self, arg):
        print "do anything 2"

    #hoge2 help
    def help_hoge2(self):
        print "help : hoge2"

    def do_EOF(self, arg):
        return True;

    #Override for empty input
    def emptyline(self):
        pass

if __name__ == '__main__':
    HogeTools().cmdloop()

intro String displayed at runtime

prompt Prompt displayed as you type

do_xxx Recognizes and executes the command xxx

help_xxx Help for do_xxx. It is executed with the command help xxx.

do_EOF Executed when ctrl + D or ʻEOFis input. You can terminate the command loop with the return valueTrue`.

emptyline Method called when blank input. If not overridden, the last non-empty command entered will be repeated.

Program execution

At startup

The values set for the instance variables ʻintro and prompt` are displayed.

(hoge)$ python ./HogeTools.py
======== something of tools ======= # intro
hogeTools)  # prompt

Complementary function

Press the tab to see a list of executable commands

hogeTools) #tab
EOF    help   hoge   hoge2
hogeTools) h #tab
help   hoge   hoge2
hogeTools) hoge #tab
hoge   hoge2

Import readline if tab completion doesn't work. (http://stackoverflow.com/questions/20994424/python-cmd-tab-completion-problems)

import readline

Execution of the defined command

xxx and help xxx execute the methods of do_xxx and help_xxx.

hogeTools) hoge
    do nothing
hogeTools) help hoge
    help : hoge

Finally

In addition, you can customize the help output (doc_header) andprecmd ()executed before the command loop. How about making such a tool in Python for a change?