"""
def __init__(self, dry = False):
self.dry = dry
+ self.cwd = None
def call(self, *args, **kwargs):
"""
Performs a system call. The actual executable and options should
specify this if you are using another wrapper around this function).
:param log: if True, we log the call as INFO, if False, we log the call
as DEBUG, otherwise, we detect based on ``strip``.
+ :param addenv: mapping of environment variables *to add*
+ :param stdout:
+ :param stderr:
+ :param stdin: a file-type object that will be written to or read from as a pipe.
:returns: a tuple of strings ``(stdout, stderr)``, or a string ``stdout``
if ``strip`` is specified.
>>> sh.call("cat", input='Foobar')
('Foobar', '')
"""
- if hasattr(self, "_wait"):
- self._wait()
+ self._wait()
kwargs.setdefault("interactive", False)
kwargs.setdefault("strip", False)
kwargs.setdefault("python", None)
kwargs.setdefault("log", None)
+ kwargs.setdefault("stdout", subprocess.PIPE)
+ kwargs.setdefault("stdin", subprocess.PIPE)
+ kwargs.setdefault("stderr", subprocess.PIPE)
+ kwargs.setdefault("addenv", None)
msg = "Running `" + ' '.join(args) + "`"
if kwargs["strip"] and not kwargs["log"] is True or kwargs["log"] is False:
logging.debug(msg)
stdin=sys.stdin
stderr=sys.stderr
else:
- stdout=subprocess.PIPE
- stdin=subprocess.PIPE
- stderr=subprocess.PIPE
+ stdout=kwargs["stdout"]
+ stdin=kwargs["stdin"]
+ stderr=kwargs["stderr"]
+ env = None
+ if kwargs["addenv"]:
+ env = dict(os.environ.items() + kwargs["addenv"].items())
# XXX: There is a possible problem here where we can fill up
# the kernel buffer if we have 64KB of data. This shouldn't
- # be a problem, and the fix for such case would be to write to
+ # normally be a problem, and the fix for such case would be to write to
# temporary files instead of a pipe.
+ #
+ # However, it *is* a problem when you do something silly, like
+ # pass --debug to mass-upgrade.
+ #
# Another possible way of fixing this is converting from a
# waitpid() pump to a select() pump, creating a pipe to
- # ourself, and then setting up a
- # SIGCHILD handler to write a single byte to the pipe to get
- # us out of select() when a subprocess exits.
- proc = subprocess.Popen(args, stdout=stdout, stderr=stderr, stdin=stdin)
- if hasattr(self, "_async"):
- self._async(proc, args, **kwargs)
+ # ourself, and then setting up a SIGCHILD handler to write a single
+ # byte to the pipe to get us out of select() when a subprocess exits.
+ proc = subprocess.Popen(args, stdout=stdout, stderr=stderr, stdin=stdin, cwd=self.cwd, env=env)
+ if self._async(proc, args, **kwargs):
return proc
stdout, stderr = proc.communicate(kwargs["input"])
+ # can occur if we were doing interactive communication; i.e.
+ # we didn't pass in PIPE.
+ if stdout is None:
+ stdout = ""
+ if stderr is None:
+ stderr = ""
if not kwargs["interactive"]:
if kwargs["strip"]:
self._log(None, stderr)
else: eclass = CallError
raise eclass(proc.returncode, args, stdout, stderr)
if kwargs["strip"]:
- return stdout.rstrip("\n")
+ return str(stdout).rstrip("\n")
return (stdout, stderr)
def _log(self, stdout, stderr):
"""Logs the standard output and standard input from a command."""
logging.debug("STDOUT:\n" + stdout)
if stderr:
logging.debug("STDERR:\n" + stderr)
+ def _wait(self):
+ pass
+ def _async(self, *args, **kwargs):
+ return False
def callAsUser(self, *args, **kwargs):
"""
Performs a system call as a different user. This is only possible
on working directory context. Keyword arguments are the
same as :meth:`call`.
"""
+ if os.getuid():
+ return self.call(*args, **kwargs)
uid = os.stat(os.getcwd()).st_uid
# consider also checking ruid?
if uid != os.geteuid():
"""
kwargs["strip"] = True
return self.call(*args, **kwargs)
+ def setcwd(self, cwd):
+ """
+ Sets the directory processes are executed in. This sets a value
+ to be passed as the ``cwd`` argument to ``subprocess.Popen``.
+ """
+ self.cwd = cwd
+ def interactive():
+ user_shell = os.getenv("SHELL")
+ if not user_shell: user_shell = "/bin/bash"
+ # XXX: scripts specific hack, since mbash doesn't respect the current working directory
+ # When the revolution comes (i.e. $ATHENA_HOMEDIR/Scripts is your Scripts home
+ # directory) this isn't strictly necessary, but we'll probably need to support
+ # web_scripts directories ad infinitum.
+ if user_shell == "/usr/local/bin/mbash": user_shell = "/bin/bash"
+
+ try:
+ self.call(user_shell, "-i", interactive=True)
+ except shell.CallError as e:
+ logging.warning("Shell returned non-zero exit code %d" % e.code)
class ParallelShell(Shell):
"""
execution. See :meth:`Shell.call` source code for details.
"""
self.running[proc.pid] = (proc, args, python, on_success, on_error)
+ return True # so that the parent function returns
def _wait(self):
"""
Blocking call that waits for an open subprocess slot. This is
automatically called by :meth:`Shell.call`.
"""
- # XXX: This API sucks; the actuall call/callAsUser call should
+ # XXX: This API sucks; the actual call/callAsUser call should
# probably block automatically (unless I have a good reason not to)
# bail out immediately on initial ramp up
if len(self.running) < self.max: return
on_error(eclass(proc.returncode, args, stdout, stderr))
return
on_success(stdout, stderr)
+ def interactive():
+ raise Error("Cannot use interactive() on parallel shell")
+# Setup a convenience global instance
+shell = Shell()
+call = shell.call
+callAsUser = shell.callAsUser
+safeCall = shell.safeCall
+eval = shell.eval
+interactive = shell.interactive
class DummyParallelShell(ParallelShell):
"""Same API as :class:`ParallelShell`, but doesn't actually
scripts.mit.edu / wizard.git / blobdiff