Create a raw input with commands inside a Python script

Question

I'm trying to implement a small script to manage a localhost with an FTP connection in Python from the command line and using the appropriate "ftplib" module. I would like to create a sort of raw input for the user but with some commands already setup.

I try to explain better:

Once I have created the FTP connection and login connection been successfully completed through username and password, i would show a sort of "bash shell" with the possibility to use the most famous UNIX commands ( for example cd and ls respectively to move in a directory and show file/folders in the current path ).

For example i could do this:

> cd "path inside localhost"

thus showing directories or:

> ls

to show all files and directories in that particular path. I've no idea how to implement this so i ask you some advices.

I thank you so much in advance for the help.

Answer 1

It sounds like the command line interface is that part that you are asking about. One good way to map user inputs to commands is to use a dictionary and the fact that in python you can run a reference to a function by putting () after it's names. Here's a quick example showing you what I mean

def firstThing():  # this could be your 'cd' task
    print 'ran first task'

def secondThing(): # another task you would want to run
    print 'ran second task'

def showCommands(): # a task to show available commands
    print functionDict.keys()

# a dictionary mapping commands to functions (you could do the same with classes)
functionDict = {'f1': firstThing, 'f2': secondThing, 'help': showCommands}

# the actual function that gets the input
def main():
    cont = True
    while(cont):
        selection = raw_input('enter your selection ')
        if selection == 'q': # quick and dirty way to give the user a way out
            cont = False
        elif selection in functionDict.keys():
            functionDict[selection]()
        else:
            print 'my friend, you do not know me. enter help to see VALID commands'

if __name__ == '__main__':
    main()