diff --git a/ansible_mitogen/connection.py b/ansible_mitogen/connection.py index fcb5851d..70b4aae9 100644 --- a/ansible_mitogen/connection.py +++ b/ansible_mitogen/connection.py @@ -88,6 +88,17 @@ def _connect_docker(spec): } +def _connect_lxc(spec): + return { + 'method': 'lxc', + 'kwargs': { + 'container': spec['remote_addr'], + 'python_path': spec['python_path'], + 'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'], + } + } + + def _connect_sudo(spec): return { 'method': 'sudo', @@ -103,10 +114,12 @@ def _connect_sudo(spec): CONNECTION_METHOD = { - 'sudo': _connect_sudo, - 'ssh': _connect_ssh, - 'local': _connect_local, 'docker': _connect_docker, + 'local': _connect_local, + 'lxc': _connect_lxc, + 'lxd': _connect_lxc, + 'ssh': _connect_ssh, + 'sudo': _connect_sudo, } @@ -494,3 +507,11 @@ class LocalConnection(Connection): class DockerConnection(Connection): transport = 'docker' + + +class LxcConnection(Connection): + transport = 'lxc' + + +class LxdConnection(Connection): + transport = 'lxd' diff --git a/ansible_mitogen/logging.py b/ansible_mitogen/logging.py index 76b42c7b..071ecd10 100644 --- a/ansible_mitogen/logging.py +++ b/ansible_mitogen/logging.py @@ -46,6 +46,9 @@ class Handler(logging.Handler): self.normal_method = normal_method def emit(self, record): + if getattr(record, 'mitogen_name', '') == 'stderr': + record.levelno = logging.ERROR + s = '[pid %d] %s' % (os.getpid(), self.format(record)) if record.levelno >= logging.ERROR: self.display.error(s, wrap_text=False) diff --git a/ansible_mitogen/plugins/connection/mitogen_lxc.py b/ansible_mitogen/plugins/connection/mitogen_lxc.py new file mode 100644 index 00000000..48d4e03d --- /dev/null +++ b/ansible_mitogen/plugins/connection/mitogen_lxc.py @@ -0,0 +1,56 @@ +# Copyright 2017, David Wilson +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are met: +# +# 1. Redistributions of source code must retain the above copyright notice, +# this list of conditions and the following disclaimer. +# +# 2. Redistributions in binary form must reproduce the above copyright notice, +# this list of conditions and the following disclaimer in the documentation +# and/or other materials provided with the distribution. +# +# 3. Neither the name of the copyright holder nor the names of its contributors +# may be used to endorse or promote products derived from this software without +# specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE +# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. + +import os.path +import sys + +# +# This is not the real Connection implementation module, it simply exists as a +# proxy to the real module, which is loaded using Python's regular import +# mechanism, to prevent Ansible's PluginLoader from making up a fake name that +# results in ansible_mitogen plugin modules being loaded twice: once by +# PluginLoader with a name like "ansible.plugins.connection.mitogen", which is +# stuffed into sys.modules even though attempting to import it will trigger an +# ImportError, and once under its canonical name, "ansible_mitogen.connection". +# +# Therefore we have a proxy module that imports it under the real name, and +# sets up the duff PluginLoader-imported module to just contain objects from +# the real module, so duplicate types don't exist in memory, and things like +# debuggers and isinstance() work predictably. +# + +try: + import ansible_mitogen +except ImportError: + base_dir = os.path.dirname(__file__) + sys.path.insert(0, os.path.abspath(os.path.join(base_dir, '../../..'))) + del base_dir + +from ansible_mitogen.connection import LxcConnection as Connection +del os +del sys diff --git a/ansible_mitogen/plugins/connection/mitogen_lxd.py b/ansible_mitogen/plugins/connection/mitogen_lxd.py new file mode 100644 index 00000000..91fcd0b7 --- /dev/null +++ b/ansible_mitogen/plugins/connection/mitogen_lxd.py @@ -0,0 +1,56 @@ +# Copyright 2017, David Wilson +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are met: +# +# 1. Redistributions of source code must retain the above copyright notice, +# this list of conditions and the following disclaimer. +# +# 2. Redistributions in binary form must reproduce the above copyright notice, +# this list of conditions and the following disclaimer in the documentation +# and/or other materials provided with the distribution. +# +# 3. Neither the name of the copyright holder nor the names of its contributors +# may be used to endorse or promote products derived from this software without +# specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE +# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. + +import os.path +import sys + +# +# This is not the real Connection implementation module, it simply exists as a +# proxy to the real module, which is loaded using Python's regular import +# mechanism, to prevent Ansible's PluginLoader from making up a fake name that +# results in ansible_mitogen plugin modules being loaded twice: once by +# PluginLoader with a name like "ansible.plugins.connection.mitogen", which is +# stuffed into sys.modules even though attempting to import it will trigger an +# ImportError, and once under its canonical name, "ansible_mitogen.connection". +# +# Therefore we have a proxy module that imports it under the real name, and +# sets up the duff PluginLoader-imported module to just contain objects from +# the real module, so duplicate types don't exist in memory, and things like +# debuggers and isinstance() work predictably. +# + +try: + import ansible_mitogen +except ImportError: + base_dir = os.path.dirname(__file__) + sys.path.insert(0, os.path.abspath(os.path.join(base_dir, '../../..'))) + del base_dir + +from ansible_mitogen.connection import LxdConnection as Connection +del os +del sys diff --git a/ansible_mitogen/strategy.py b/ansible_mitogen/strategy.py index ef6a37ac..05febb85 100644 --- a/ansible_mitogen/strategy.py +++ b/ansible_mitogen/strategy.py @@ -68,7 +68,7 @@ def wrap_connection_loader__get(name, play_context, new_stdin, **kwargs): 'mitogen' connection type, passing the original transport name into it as an argument, so that it can emulate the original type. """ - if name in ('ssh', 'local', 'docker'): + if name in ('ssh', 'local', 'docker', 'lxc', 'lxd'): name = 'mitogen_' + name return connection_loader__get(name, play_context, new_stdin, **kwargs) diff --git a/docs/ansible.rst b/docs/ansible.rst index 6ac03ca0..aef27b92 100644 --- a/docs/ansible.rst +++ b/docs/ansible.rst @@ -116,8 +116,8 @@ Noteworthy Differences * The ``sudo`` become method is available and ``su`` is planned. File bugs to register interest in additional methods. -* The ``ssh``, ``local`` and ``docker`` connection types are available, with - more planned. File bugs to register interest. +* The ``docker``, ``local``, ``lxc`` and ``ssh`` connection types are + available, with more planned. File bugs to register interest. * Local commands execute in a reuseable interpreter created identically to interpreters on targets. Presently one interpreter per ``become_user`` @@ -167,7 +167,7 @@ Connection Delegation Included is a preview of **Connection Delegation**, a Mitogen-specific implementation of `stackable connection plug-ins`_. This enables multi-hop -connections via a bastion, or Docker connections delegated via their host +connections via a bastion, or Docker/LCX connections delegated via their host machine, where reaching the host may itself entail recursive delegation. .. _Stackable connection plug-ins: https://github.com/ansible/proposals/issues/25 @@ -467,10 +467,24 @@ Sudo Docker ~~~~~~ -Docker support has received relatively little testing, expect increased -probability of surprises for the time being. +Docker support is fairly new, expect increased surprises for now. -* ``ansible_host`` +* ``ansible_host``: Name of Docker container. +* ``ansible_user``: Name of user within the container to execute as. + + +LXC +~~~ + +LXC support is fairly new, expect increased surprises for now. Both ``lxc`` and +``lxd`` connection plug-ins are hijacked, however the resulting implementation +always uses the ``lxc-attach`` command line tool rather than th LXC Python +bindings. + +Consequently the ``lxc-attach`` command is required to be available on the host +machine. + +* ``ansible_host``: Name of LXC container. Debugging diff --git a/docs/api.rst b/docs/api.rst index f69f1405..6186ed4f 100644 --- a/docs/api.rst +++ b/docs/api.rst @@ -17,6 +17,7 @@ mitogen Package .. automodule:: mitogen +.. autodata:: mitogen.__version__ .. autodata:: mitogen.is_master .. autodata:: mitogen.context_id .. autodata:: mitogen.parent_id @@ -711,6 +712,20 @@ Router Class Filename or complete path to the Docker binary. ``PATH`` will be searched if given as a filename. Defaults to ``docker``. + .. method:: lxc (container, lxc_attach_path=None, \**kwargs) + + Construct a context on the local machine within an LXC container. The + ``lxc-attach`` program must be available. + + Accepts all parameters accepted by :py:meth:`local`, in addition to: + + :param str container: + Existing container to connect to. Defaults to ``None``. + :param str lxc_attach_path: + Filename or complete path to the ``lxc-attach`` binary. ``PATH`` + will be searched if given as a filename. Defaults to + ``lxc-attach``. + .. method:: sudo (username=None, sudo_path=None, password=None, \**kwargs) Construct a context on the local machine over a ``sudo`` invocation. diff --git a/docs/conf.py b/docs/conf.py index 6db8ae56..7c218f8b 100644 --- a/docs/conf.py +++ b/docs/conf.py @@ -1,6 +1,17 @@ +import os import sys + sys.path.append('..') +def grep_version(): + path = os.path.join(os.path.dirname(__file__), '../mitogen/__init__.py') + with open(path) as fp: + for line in fp: + if line.startswith('__version__'): + _, _, s = line.partition('=') + return '.'.join(map(str, eval(s))) + + author = u'David Wilson' copyright = u'2016, David Wilson' exclude_patterns = ['_build'] @@ -20,8 +31,8 @@ language = None master_doc = 'toc' project = u'Mitogen' pygments_style = 'sphinx' -release = u'master' +release = grep_version() source_suffix = '.rst' templates_path = ['_templates'] todo_include_todos = False -version = u'master' +version = grep_version() diff --git a/docs/getting_started.rst b/docs/getting_started.rst index 21bc0c35..3b50e757 100644 --- a/docs/getting_started.rst +++ b/docs/getting_started.rst @@ -125,6 +125,19 @@ Logging Environment Variables logs of any IO interaction, which is useful when debugging deadlocks. + +Logging Records +~~~~~~~~~~~~~~~ + +Messages received from a child context via :class:`mitogen.master.LogForwarder` +receive extra attributes: + +* `mitogen_context`: :class:`mitogen.master.Context` referring to the message + source. +* `mitogen_name`: original logger name in the source context. +* `mitogen_msg`: original message in the source context. + + Creating A Context ------------------ diff --git a/docs/toc.rst b/docs/toc.rst index bfb35e59..f0a3b081 100644 --- a/docs/toc.rst +++ b/docs/toc.rst @@ -13,3 +13,4 @@ Table Of Contents examples internals shame + changelog diff --git a/mitogen/__init__.py b/mitogen/__init__.py index 0d5a1b13..02be6897 100644 --- a/mitogen/__init__.py +++ b/mitogen/__init__.py @@ -31,6 +31,11 @@ On the Mitogen master, this is imported from ``mitogen/__init__.py`` as would be expected. On the slave, it is built dynamically during startup. """ + +#: Library version as a tuple. +__version__ = (0, 0, 2) + + #: This is ``False`` in slave contexts. It is used in single-file Python #: programs to avoid reexecuting the program's :py:func:`main` function in the #: slave. For example: diff --git a/mitogen/core.py b/mitogen/core.py index 4a48dac0..0dd669af 100644 --- a/mitogen/core.py +++ b/mitogen/core.py @@ -485,8 +485,10 @@ class Importer(object): self._present = {'mitogen': [ 'compat', 'debug', + 'docker', 'fakessh', 'fork', + 'lxc', 'master', 'parent', 'service', @@ -1585,7 +1587,8 @@ class ExternalContext(object): sys.modules['mitogen.core'] = mitogen.core del sys.modules['__main__'] - def _setup_globals(self, context_id, parent_ids): + def _setup_globals(self, version, context_id, parent_ids): + mitogen.__version__ = version mitogen.is_master = False mitogen.context_id = context_id mitogen.parent_ids = parent_ids @@ -1645,7 +1648,7 @@ class ExternalContext(object): self.dispatch_stopped = True def main(self, parent_ids, context_id, debug, profiling, log_level, - max_message_size, in_fd=100, out_fd=1, core_src_fd=101, + max_message_size, version, in_fd=100, out_fd=1, core_src_fd=101, setup_stdio=True, setup_package=True, importer=None, whitelist=(), blacklist=()): self._setup_master(max_message_size, profiling, parent_ids[0], @@ -1656,7 +1659,7 @@ class ExternalContext(object): self._setup_importer(importer, core_src_fd, whitelist, blacklist) if setup_package: self._setup_package() - self._setup_globals(context_id, parent_ids) + self._setup_globals(version, context_id, parent_ids) if setup_stdio: self._setup_stdio() diff --git a/mitogen/docker.py b/mitogen/docker.py index 159579fc..c265dc4f 100644 --- a/mitogen/docker.py +++ b/mitogen/docker.py @@ -38,9 +38,12 @@ LOG = logging.getLogger(__name__) class Stream(mitogen.parent.Stream): container = None image = None + username = None docker_path = 'docker' - def construct(self, container=None, image=None, docker_path=None, **kwargs): + def construct(self, container=None, image=None, + docker_path=None, username=None, + **kwargs): assert container or image super(Stream, self).construct(**kwargs) if container: @@ -49,16 +52,22 @@ class Stream(mitogen.parent.Stream): self.image = image if docker_path: self.docker_path = docker_path + if username: + self.username = username def connect(self): super(Stream, self).connect() self.name = 'docker.' + (self.container or self.image) def get_boot_command(self): + args = ['--interactive'] + if self.username: + args += ['--user=' + self.username] + bits = [self.docker_path] if self.container: - bits += ['exec', '-i', self.container] + bits += ['exec'] + args + [self.container] elif self.image: - bits += ['run', '-i', '--rm', self.image] - bits += super(Stream, self).get_boot_command() - return bits + bits += ['run'] + args + ['--rm', self.image] + + return bits + super(Stream, self).get_boot_command() diff --git a/mitogen/fakessh.py b/mitogen/fakessh.py index 6a7303ab..0e737c21 100644 --- a/mitogen/fakessh.py +++ b/mitogen/fakessh.py @@ -350,6 +350,7 @@ def run(dest, router, args, deadline=None, econtext=None): 'parent_ids': parent_ids, 'profiling': getattr(router, 'profiling', False), 'setup_stdio': False, + 'version': mitogen.__version__, },)) finally: fp.close() diff --git a/mitogen/lxc.py b/mitogen/lxc.py new file mode 100644 index 00000000..73babc01 --- /dev/null +++ b/mitogen/lxc.py @@ -0,0 +1,68 @@ +# Copyright 2017, David Wilson +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are met: +# +# 1. Redistributions of source code must retain the above copyright notice, +# this list of conditions and the following disclaimer. +# +# 2. Redistributions in binary form must reproduce the above copyright notice, +# this list of conditions and the following disclaimer in the documentation +# and/or other materials provided with the distribution. +# +# 3. Neither the name of the copyright holder nor the names of its contributors +# may be used to endorse or promote products derived from this software without +# specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE +# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. + +import logging + +import mitogen.core +import mitogen.parent + + +LOG = logging.getLogger(__name__) + + +class Stream(mitogen.parent.Stream): + create_child_args = { + # If lxc-attach finds any of stdin, stdout, stderr connected to a TTY, + # to prevent input injection it creates a proxy pty, forcing all IO to + # be buffered in <4KiB chunks. So ensure stderr is also routed to the + # socketpair. + 'merge_stdio': True + } + + container = None + lxc_attach_path = 'lxc-attach' + + def construct(self, container, lxc_attach_path=None, **kwargs): + super(Stream, self).construct(**kwargs) + if container: + self.container = container + if lxc_attach_path: + self.lxc_attach_path = lxc_attach_apth + + def connect(self): + super(Stream, self).connect() + self.name = 'lxc.' + self.container + + def get_boot_command(self): + bits = [ + self.lxc_attach_path, + '--clear-env', + '--name', self.container, + '--', + ] + return bits + super(Stream, self).get_boot_command() diff --git a/mitogen/master.py b/mitogen/master.py index 1e46a916..d0bc55a8 100644 --- a/mitogen/master.py +++ b/mitogen/master.py @@ -309,7 +309,11 @@ class LogForwarder(object): self._cache[msg.src_id] = logger = logging.getLogger(name) name, level_s, s = msg.data.split('\x00', 2) - logger.log(int(level_s), '%s: %s', name, s) + logger.log(int(level_s), '%s: %s', name, s, extra={ + 'mitogen_message': s, + 'mitogen_context': self._router.context_by_id(msg.src_id), + 'mitogen_name': name, + }) def __repr__(self): return 'LogForwarder(%r)' % (self._router,) diff --git a/mitogen/parent.py b/mitogen/parent.py index 2868c93a..501cfce2 100644 --- a/mitogen/parent.py +++ b/mitogen/parent.py @@ -243,10 +243,17 @@ def create_socketpair(): return parentfp, childfp -def create_child(*args): +def create_child(args, merge_stdio=False): """ Create a child process whose stdin/stdout is connected to a socket. + :param args: + Argument vector for execv() call. + :param bool merge_stdio: + If :data:`True`, arrange for `stderr` to be connected to the `stdout` + socketpair, rather than inherited from the parent process. This may be + necessary to ensure that not TTY is connected to any stdio handle, for + instance when using LXC. :returns: `(pid, socket_obj, :data:`None`)` """ @@ -257,11 +264,17 @@ def create_child(*args): # O_NONBLOCK from Python's future stdin fd. mitogen.core.set_block(childfp.fileno()) + if merge_stdio: + extra = {'stderr': childfp} + else: + extra = {} + proc = subprocess.Popen( args=args, stdin=childfp, stdout=childfp, close_fds=True, + **extra ) childfp.close() # Decouple the socket from the lifetime of the Python socket object. @@ -284,7 +297,7 @@ def _acquire_controlling_tty(): fcntl.ioctl(2, termios.TIOCSCTTY) -def tty_create_child(*args): +def tty_create_child(args): """ Return a file descriptor connected to the master end of a pseudo-terminal, whose slave end is connected to stdin/stdout/stderr of a new child process. @@ -318,7 +331,7 @@ def tty_create_child(*args): return proc.pid, master_fd, None -def hybrid_tty_create_child(*args): +def hybrid_tty_create_child(args): """ Like :func:`tty_create_child`, except attach stdin/stdout to a socketpair like :func:`create_child`, but leave stderr and the controlling TTY @@ -685,6 +698,7 @@ class Stream(mitogen.core.Stream): 'whitelist': self._router.get_module_whitelist(), 'blacklist': self._router.get_module_blacklist(), 'max_message_size': self.max_message_size, + 'version': mitogen.__version__, } def get_preamble(self): @@ -695,12 +709,13 @@ class Stream(mitogen.core.Stream): return zlib.compress(minimize_source(source), 9) create_child = staticmethod(create_child) + create_child_args = {} name_prefix = 'local' def start_child(self): args = self.get_boot_command() try: - return self.create_child(*args) + return self.create_child(args, **self.create_child_args) except OSError: e = sys.exc_info()[1] msg = 'Child start failed: %s. Command was: %s' % (e, Argv(args)) @@ -993,6 +1008,9 @@ class Router(mitogen.core.Router): self._context_by_id[context.context_id] = context return context + def lxc(self, **kwargs): + return self.connect('lxc', **kwargs) + def docker(self, **kwargs): return self.connect('docker', **kwargs) diff --git a/setup.py b/setup.py index af41c13a..a4ec07ba 100644 --- a/setup.py +++ b/setup.py @@ -28,9 +28,19 @@ from setuptools import find_packages, setup + +def grep_version(): + path = os.path.join(os.path.dirname(__file__), 'mitogen/__init__.py') + with open(path) as fp: + for line in fp: + if line.startswith('__version__'): + _, _, s = line.partition('=') + return '.'.join(map(str, eval(s))) + + setup( name = 'mitogen', - version = '0.0.2', + version = grep_version(), description = 'Library for writing distributed self-replicating programs.', author = 'David Wilson', license = 'New BSD', diff --git a/tests/parent_test.py b/tests/parent_test.py index c8c2e876..888ed186 100644 --- a/tests/parent_test.py +++ b/tests/parent_test.py @@ -117,9 +117,9 @@ class TtyCreateChildTest(unittest2.TestCase): # read a password. tf = tempfile.NamedTemporaryFile() try: - pid, fd, _ = self.func( + pid, fd, _ = self.func([ 'bash', '-c', 'exec 2>%s; echo hi > /dev/tty' % (tf.name,) - ) + ]) deadline = time.time() + 5.0 for line in mitogen.parent.iter_read([fd], deadline): self.assertEquals('hi\n', line)