citizenshell

citizenshell is a python library allowing to execute shell commands either locally or remotely over several protocols (telnet, ssh, serial or adb) using a simple and consistent API. This library is compatible with both python 2 (2.7) and 3 (>=3.4) as well as with PyPy. For now, it focuses on POSIX platforms like Linux and MacOS, but may be extended to work to Windows based platform in the future. It is distributed under MIT license.

Installation

citizenshell can simply installed using pip install citizenshell

Obtaining a shell

First you need a shell. For that you have several options:

1. use the built-in LocalShell for quick access:

   from citizenshell import sh

2. you can instanciate your own LocalShell:

   from citizenshell import LocalShell
   
   shell = LocalShell()

3. you can instanciate the TelnetShell for shell over telnet:

   from citizenshell import TelnetShell
   
   shell = TelnetShell(hostname="acme.org", username="john",
                       password="secretpassword")

4. you can instanciate the SecureShell for shell over SSH:

   from citizenshell import SecureShell
   
   shell = SecureShell(hostname="acme.org", username="john",
                       password="secretpassword")

5. you can instanciate the AdbShell for shell over ADB:

   from citizenshell import AdbShell
   
   shell = AdbShell(hostname="acme.org", username="john",
                    password="secretpassword")

6. you can instanciate the SerialShell for shell over serial line:

   from serial import EIGHTBITS, PARITY_NONE
   from citizenshell import SerialShell
   
   shell = SerialShell(port="/dev/ttyUSB3", username="john",
                       password="secretpassword",
                       baudrate=115200, parity=PARITY_NONE, bytesize=EIGHTBITS)

7. you can also obtain shell objects by URI using the Shell function:

   from citizenshell import Shell
   
   localshell = Shell()
   telnetshell = Shell("telnet://john:secretpassword@acme.org:1234")
   secureshell = Shell("ssh://john:secretpassword@acme.org:1234")
   adbshell = Shell("adb://myandroiddevice:5555")
   serialshell = Shell("serial://jogn:secretpassword@/dev/ttyUSB3?baudrate=115200")

   you can also mix and match betweens providing arguments in the URI or via kwargs:

   telnetshell = Shell("telnet://john@acme.org", password="secretpassword", port=1234)
   serialshell = Shell("serial://john:secretpassword@/dev/ttyUSB3", baudrate=115200)

Using a shell

Once you have shell, any shell, you can call it directly and get the standart output:

assert shell("echo Hello World") == "Hello World"

or you can also iterate over the standard output:

result = [int(x) for x in shell("""
    for i in 1 2 3 4; do
        echo $i;
    done
""")]
assert result == [1, 2, 3, 4]

you don't have to wait for the command to finish to recieve the lines:

for line in shell("for i in 1 2 3 4; do echo -n 'It is '; date +%H:%M:%S; sleep 1; done", wait=False)
    print ">>>", line + "!"

would produce something like:

>>> It is 14:24:52!
>>> It is 14:24:53!
>>> It is 14:24:54!
>>> It is 14:24:55!

you can extract stdout, stderr and exit code seperately:

result = shell(">&2 echo error && echo output && exit 13")
assert result.stdout() == ["output"]
assert result.stderr() == ["error"]
assert result.exit_code() == 13

you can inject environment variable to the shell

assert shell("echo $VAR", VAR="bar") == "bar"

or have the shell raise an exception if the exit code is non-zero:

assert shell("exit 13").exit_code() == 13 # will not raise any exception
try:
    shell("exit 13", check_xc=True) # will raise an exception
    assert False, "will not be reached"
except ShellError as e:
    assert True, "will be reached"

the shell can also raise an exception if something is printed on the standard error:

shell("echo DANGER >&2").stderr() == ["DANGER"] # will not raise any exception
try:
    shell("echo DANGER >&2", check_err=True) # will raise an exception
    assert False, "will not be reached"
except ShellError as e:
    assert True, "will be reached"

you can pull file from the remote host (for LocalShell it's just doing a copy):

shell("echo -n test > remote_file.txt")
shell.pull("local_file.txt", "remote_file.txt")
assert open("local_file.txt", "r").read() == "test"

or push file to the remote host (again, for LocalShell it's just doing a copy):

open("local_file.txt", "w").write("test")
shell.push("local_file.txt", "remote_file.txt")
assert str(shell("cat remote_file.txt")) == "test"