[Gambas-user] Interaction With Command Shell

[Benoît Minisini]

Le 16/03/2015 22:44, Tobias Boege a écrit :
> On Mon, 16 Mar 2015, Beno?t Minisini wrote:
>> Le 16/03/2015 16:31, Tobias Boege a ?crit :
>>> On Mon, 16 Mar 2015, Nigel Verity wrote:
>>>> Hi
>>>>
>>>> I would welcome some advice about interacting with the Linux command shell from within a Gambas application.
>>>>
>>>> The requirement is to create a connection with a remote server using SSHFS. The general syntax for this command is:
>>>>
>>>> sshfs username at ...3453...:/foldername /local-mount-folder
>>>>
>>>> There is no option in the SSHFS command to include the user's password on the remote server. When running from a command prompt, once the sshfs command is accepted you are then prompted to enter the password.
>>>>
>>>> Is there any way, after executing the SSHFS command (using SHELL, presumably) to monitor for the password prompt and then send the password to the command shell?
>>>>
>>>> My aim is to create a dialog in which the user provides the server name, username and password and have Gambas do the rest to create the SSHFS connection.
>>>>
>>>
>>> I have once tried that, specifically with sshfs, too, and failed miserably.
>>> Your zeroth approximation should be to factor out Gambas and write a shell
>>> script which can pass the password to sshfs. If you've got that, you almost
>>> have the solution in Gambas.
>>>
>>> There is a program "expect" which was designed for specifically the purpose
>>> of waiting on a program's output for a specific pattern and then sending a
>>> given string to its input (i.e. to automate interactive programs). But it
>>> seems sshfs is putting extra effort into preventing this automation.
>>>
>>> I ended up creating a private/public key pair and have the server work with
>>> that so that I can login using these keys[0]. Maybe this is an option for
>>> you, too?
>>>
>>> If you can trick sshfs into being automated via expect or some other means,
>>> please let me know :-)
>>>
>>> Regards,
>>> Tobi
>>>
>>> [0] https://help.ubuntu.com/community/SSH/OpenSSH/Keys
>>>
>>
>> I'm automating scp and ssh daily with Gambas, by detecting when the
>> password prompt appears (and the ssh key confirmation question too).
>>
>> It cannot be 100% reliable, because any other program can print
>> "password:" on its standard output, and apparently there is no way to
>> know that a program is waiting for input.
>>
>> But in practise it works.
>>
>> If there is no clean way to do that, maybe I should make a component
>> with that, even it's some quick & dirty hack?
>>
>
> I would definitely like to see it. I have a project here which can pipe a
> password into sudo and I remember seeing forum threads where others could
> automate sshfs mounts but all those approaches didn't work with my sshfs.
> (That's why I suspected that they put extra effort into preventing auto-
>   mation, be it for their amusement or to discipline users.)
>
> Regards,
> Tobi
>

The idea would be the ability to define the concept of "command that 
sometimes asks for a password or something else", which would be linked 
with a list of command executable names, a prompt, and what to answer.

As, "of course", each command do as it wants, and often commands run 
other commands that could prompt too (for example, svn uses the ssh 
protocol, but cannot give it any password, and ask for it several times).

And, "of course", each command must be run in english, as we will not 
store the different prompts for all possible languages.

I know the prompts of ssh, scp, and svn (but maybe not all). For other 
commands, I need the knowledge of the Gambas community!

If you have other ideas about that, just tell.

Regards,

-- 
Benoît Minisini