How to use ptyprocess - 10 common examples

# helper for running sut as subprocess within pty
# does two things
# * test app running in pty in subprocess
# * get test coverage from subprocess

# docu:
# http://blog.fizyk.net.pl/blog/gathering-tests-coverage-for-subprocesses-in-python.html


PY3 = sys.version_info[0] >= 3

if PY3:
    basestring = str


class SimplePty(PtyProcess):
    """Simple wrapper around a process running in a pseudoterminal.

    This class exposes a similar interface to :class:`PtyProcess`, but its read
    methods return unicode, and its :meth:`write` accepts unicode.
    """

    def __init__(self, pid, fd, encoding='utf-8', codec_errors='strict'):
        super(SimplePty, self).__init__(pid, fd)
        self.encoding = encoding
        self.codec_errors = codec_errors
        self.decoder = codecs.getincrementaldecoder(encoding)(errors=codec_errors)

    def read(self, size=1024):
        """Read at most ``size`` bytes from the pty, return them as unicode.

        Can block if there is nothing to read. Raises :exc:`EOFError` if the

import time
import os

if sys.platform.startswith("win"):
    import winpty
else:
    import ptyprocess


__all__ = ["PtyProcess", "Screen", "ByteStream", "Terminal"]


if sys.platform.startswith("win"):
    ParentPtyProcess = winpty.PtyProcess
else:
    ParentPtyProcess = ptyprocess.PtyProcess


class PtyProcess(ParentPtyProcess):

    def read(self, nbytes):
        if sys.platform.startswith("win"):
            return super(PtyProcess, self).read(nbytes).encode("utf-8")
        else:
            return super(PtyProcess, self).read(nbytes)

    def write(self, data):
        if sys.platform.startswith("win"):
            super(PtyProcess, self).write(data.decode("utf-8"))
        else:
            super(PtyProcess, self).write(data)

ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

'''
from __future__ import print_function

import pexpect
import unittest
from . import PexpectTestCase
import time
import sys

from ptyprocess import ptyprocess
ptyprocess._make_eof_intr()

if sys.version_info[0] >= 3:
    def byte(i):
        return bytes([i])
else:
    byte = chr

class TestCtrlChars(PexpectTestCase.PexpectTestCase):
    def setUp(self):
        super(TestCtrlChars, self).setUp()
        self.getch_cmd = self.PYTHONBIN + ' getch.py'

    def test_control_chars(self):
        '''This tests that we can send all 256 8-bit characters to a child
        process.'''
        child = pexpect.spawn(self.getch_cmd, echo=False, timeout=5)

def test_sendeof(self):
        child = pexpect.spawn(self.getch_cmd, echo=False, timeout=5)
        child.expect('READY')
        child.sendeof()
        child.expect(str(ord(ptyprocess._EOF)) + '

def test_sendintr (self):
        child = pexpect.spawn(self.getch_cmd, echo=False, timeout=5)
        child.expect('READY')
        child.sendintr()
        child.expect(str(ord(ptyprocess._INTR)) + '

def open(self):
        """Open ThreadedTerminal connection & start thread pulling data from it."""
        ret = super(ThreadedTerminal, self).open()

        if not self._terminal:
            self._terminal = PtyProcessUnicode.spawn(self._cmd, dimensions=self.dimensions)
            # need to not replace not unicode data instead of raise exception
            self._terminal.decoder = codecs.getincrementaldecoder('utf-8')(errors='replace')

            done = Event()
            self.pulling_thread = TillDoneThread(target=self.pull_data,
                                                 done_event=done,
                                                 kwargs={'pulling_done': done})
            self.pulling_thread.start()
            retry = 0
            is_operable = False

            while (retry < 3) and (not is_operable):
                is_operable = self._shell_operable.wait(timeout=1)
                if not is_operable:
                    self.logger.warning("Terminal open but not fully operable yet")
                    self._terminal.write('\n')

def disconnect(self):
        if self.vpn_process is not None:
            try:
                self._terminate()
            except ValueError:
                self._kill()
            time.sleep(0.5)
            while self._is_running:
                if self.use_pexpect:
                    try:
                        self.vpn_process.close(True)
                    except ptyprocess.ptyprocess.PtyProcessError:
                        pass
                else:
                    self.vpn_process.wait()
                time.sleep(0.1)
            self.connected = False
            try:
                self.instances.remove(self)
            except ValueError:
                pass
            self.vpn_process = self.ip = self.conf_file = None
            self.log.info('Disconnected')
        else:
            self.log.warning('Not connected')

def _spawnpty(self, args, **kwargs):
        '''Spawn a pty and return an instance of PtyProcess.'''
        return ptyprocess.PtyProcess.spawn(args, **kwargs)

assert self.pid is None, 'The pid member must be None.'
        assert self.command is not None, 'The command member must not be None.'

        kwargs = {'echo': self.echo, 'preexec_fn': preexec_fn}
        if self.ignore_sighup:
            def preexec_wrapper():
                "Set SIGHUP to be ignored, then call the real preexec_fn"
                signal.signal(signal.SIGHUP, signal.SIG_IGN)
                if preexec_fn is not None:
                    preexec_fn()
            kwargs['preexec_fn'] = preexec_wrapper

        if dimensions is not None:
            kwargs['dimensions'] = dimensions

        self.ptyproc = ptyprocess.PtyProcess.spawn(self.args, env=self.env,
                                                   cwd=self.cwd, **kwargs)

        self.pid = self.ptyproc.pid
        self.child_fd = self.ptyproc.fd


        self.terminated = False
        self.closed = False

def _spawnpty(self, args, **kwargs):
        '''Spawn a pty and return an instance of PtyProcess.'''
        return ptyprocess.PtyProcess.spawn(args, **kwargs)