2 # NEPI, a framework to manage network experiments
3 # Copyright (C) 2013 INRIA
5 # This program is free software: you can redistribute it and/or modify
6 # it under the terms of the GNU General Public License as published by
7 # the Free Software Foundation, either version 3 of the License, or
8 # (at your option) any later version.
10 # This program is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 # GNU General Public License for more details.
15 # You should have received a copy of the GNU General Public License
16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18 # Author: Alina Quereilhac <alina.quereilhac@inria.fr>
20 from nepi.execution.attribute import Attribute, Flags, Types
21 from nepi.execution.resource import ResourceManager, clsinit_copy, \
22 ResourceState, reschedule_delay
23 from nepi.resources.linux import rpmfuncs, debfuncs
24 from nepi.util import sshfuncs, execfuncs
25 from nepi.util.sshfuncs import ProcStatus
36 # TODO: Unify delays!!
37 # TODO: Validate outcome of uploads!!
41 Error codes that the rexitcode function can return if unable to
42 check the exit code of a spawned process
51 Supported flavors of Linux OS
61 class LinuxNode(ResourceManager):
63 .. class:: Class Args :
65 :param ec: The Experiment controller
66 :type ec: ExperimentController
67 :param guid: guid of the RM
72 There are different ways in which commands can be executed using the
73 LinuxNode interface (i.e. 'execute' - blocking and non blocking, 'run',
78 * 'execute' (blocking mode) :
80 HOW IT WORKS: 'execute', forks a process and run the
81 command, synchronously, attached to the terminal, in
83 The execute method will block until the command returns
84 the result on 'out', 'err' (so until it finishes executing).
86 USAGE: short-lived commands that must be executed attached
87 to a terminal and in foreground, for which it IS necessary
88 to block until the command has finished (e.g. if you want
89 to run 'ls' or 'cat').
91 * 'execute' (NON blocking mode - blocking = False) :
93 HOW IT WORKS: Same as before, except that execute method
94 will return immediately (even if command still running).
96 USAGE: long-lived commands that must be executed attached
97 to a terminal and in foreground, but for which it is not
98 necessary to block until the command has finished. (e.g.
99 start an application using X11 forwarding)
103 HOW IT WORKS: Connects to the host ( using SSH if remote)
104 and launches the command in background, detached from any
105 terminal (daemonized), and returns. The command continues to
106 run remotely, but since it is detached from the terminal,
107 its pipes (stdin, stdout, stderr) can't be redirected to the
108 console (as normal non detached processes would), and so they
109 are explicitly redirected to files. The pidfile is created as
110 part of the process of launching the command. The pidfile
111 holds the pid and ppid of the process forked in background,
112 so later on it is possible to check whether the command is still
115 USAGE: long-lived commands that can run detached in background,
116 for which it is NOT necessary to block (wait) until the command
117 has finished. (e.g. start an application that is not using X11
118 forwarding. It can run detached and remotely in background)
122 HOW IT WORKS: Similar to 'run' except that it 'blocks' until
123 the command has finished execution. It also checks whether
124 errors occurred during runtime by reading the exitcode file,
125 which contains the exit code of the command that was run
126 (checking stderr only is not always reliable since many
127 commands throw debugging info to stderr and the only way to
128 automatically know whether an error really happened is to
129 check the process exit code).
131 Another difference with respect to 'run', is that instead
132 of directly executing the command as a bash command line,
133 it uploads the command to a bash script and runs the script.
134 This allows to use the bash script to debug errors, since
135 it remains at the remote host and can be run manually to
138 USAGE: medium-lived commands that can run detached in
139 background, for which it IS necessary to block (wait) until
140 the command has finished. (e.g. Package installation,
141 source compilation, file download, etc)
145 _help = "Controls Linux host machines ( either localhost or a host " \
146 "that can be accessed using a SSH key)"
147 _backend_type = "linux"
150 def _register_attributes(cls):
151 hostname = Attribute("hostname", "Hostname of the machine",
152 flags = Flags.ExecReadOnly)
154 username = Attribute("username", "Local account username",
155 flags = Flags.Credential)
157 port = Attribute("port", "SSH port", flags = Flags.ExecReadOnly)
159 home = Attribute("home",
160 "Experiment home directory to store all experiment related files",
161 flags = Flags.ExecReadOnly)
163 identity = Attribute("identity", "SSH identity file",
164 flags = Flags.Credential)
166 server_key = Attribute("serverKey", "Server public key",
167 flags = Flags.ExecReadOnly)
169 clean_home = Attribute("cleanHome", "Remove all nepi files and directories "
170 " from node home folder before starting experiment",
173 flags = Flags.ExecReadOnly)
175 clean_experiment = Attribute("cleanExperiment", "Remove all files and directories "
176 " from a previous same experiment, before the new experiment starts",
179 flags = Flags.ExecReadOnly)
181 clean_processes = Attribute("cleanProcesses",
182 "Kill all running processes before starting experiment",
185 flags = Flags.ExecReadOnly)
187 tear_down = Attribute("tearDown", "Bash script to be executed before " + \
188 "releasing the resource",
189 flags = Flags.ExecReadOnly)
191 cls._register_attribute(hostname)
192 cls._register_attribute(username)
193 cls._register_attribute(port)
194 cls._register_attribute(home)
195 cls._register_attribute(identity)
196 cls._register_attribute(server_key)
197 cls._register_attribute(clean_home)
198 cls._register_attribute(clean_experiment)
199 cls._register_attribute(clean_processes)
200 cls._register_attribute(tear_down)
202 def __init__(self, ec, guid):
203 super(LinuxNode, self).__init__(ec, guid)
205 # home directory at Linux host
208 # lock to prevent concurrent applications on the same node,
209 # to execute commands at the same time. There are potential
210 # concurrency issues when using SSH to a same host from
211 # multiple threads. There are also possible operational
212 # issues, e.g. an application querying the existence
213 # of a file or folder prior to its creation, and another
214 # application creating the same file or folder in between.
215 self._node_lock = threading.Lock()
217 def log_message(self, msg):
218 return " guid %d - host %s - %s " % (self.guid,
219 self.get("hostname"), msg)
223 home = self.get("home") or ""
224 if not home.startswith("/"):
225 home = os.path.join(self._home_dir, home)
230 return os.path.join(self.home_dir, "nepi-usr")
234 return os.path.join(self.usr_dir, "lib")
238 return os.path.join(self.usr_dir, "bin")
242 return os.path.join(self.usr_dir, "src")
246 return os.path.join(self.usr_dir, "share")
250 return os.path.join(self.home_dir, "nepi-exp")
254 return os.path.join(self.exp_dir, self.ec.exp_id)
258 return os.path.join(self.exp_home, "node-%d" % self.guid)
262 return os.path.join(self.node_home, self.ec.run_id)
269 if (not self.get("hostname") or not self.get("username")):
270 msg = "Can't resolve OS, insufficient data "
272 raise RuntimeError, msg
276 if out.find("Fedora release 8") == 0:
277 self._os = OSType.FEDORA_8
278 elif out.find("Fedora release 12") == 0:
279 self._os = OSType.FEDORA_12
280 elif out.find("Fedora release 14") == 0:
281 self._os = OSType.FEDORA_14
282 elif out.find("Fedora release") == 0:
283 self._os = OSType.FEDORA
284 elif out.find("Debian") == 0:
285 self._os = OSType.DEBIAN
286 elif out.find("Ubuntu") ==0:
287 self._os = OSType.UBUNTU
289 msg = "Unsupported OS"
291 raise RuntimeError, "%s - %s " %( msg, out )
296 # The underlying SSH layer will sometimes return an empty
297 # output (even if the command was executed without errors).
298 # To work arround this, repeat the operation N times or
299 # until the result is not empty string
304 (out, err), proc = self.execute("cat /etc/issue",
309 if out.strip() != "":
312 trace = traceback.format_exc()
313 msg = "Error detecting OS: %s " % trace
314 self.error(msg, out, err)
317 time.sleep(min(30.0, retrydelay))
322 return self.os in [OSType.DEBIAN, OSType.UBUNTU]
326 return self.os in [OSType.FEDORA_12, OSType.FEDORA_14, OSType.FEDORA_8,
331 return self.get("hostname") in ['localhost', '127.0.0.7', '::1']
333 def do_provision(self):
334 # check if host is alive
335 if not self.is_alive():
336 msg = "Deploy failed. Unresponsive node %s" % self.get("hostname")
338 raise RuntimeError, msg
342 if self.get("cleanProcesses"):
343 self.clean_processes()
345 if self.get("cleanHome"):
348 if self.get("cleanExperiment"):
349 self.clean_experiment()
351 # Create shared directory structure
352 self.mkdir(self.lib_dir)
353 self.mkdir(self.bin_dir)
354 self.mkdir(self.src_dir)
355 self.mkdir(self.share_dir)
357 # Create experiment node home directory
358 self.mkdir(self.node_home)
360 super(LinuxNode, self).do_provision()
363 if self.state == ResourceState.NEW:
364 self.info("Deploying node")
368 # Node needs to wait until all associated interfaces are
369 # ready before it can finalize deployment
370 from nepi.resources.linux.interface import LinuxInterface
371 ifaces = self.get_connected(LinuxInterface.rtype())
373 if iface.state < ResourceState.READY:
374 self.ec.schedule(reschedule_delay, self.deploy)
377 super(LinuxNode, self).do_deploy()
379 def do_release(self):
380 rms = self.get_connected()
382 # Node needs to wait until all associated RMs are released
383 # before it can be released
384 if rm.state != ResourceState.RELEASED:
385 self.ec.schedule(reschedule_delay, self.release)
388 tear_down = self.get("tearDown")
390 self.execute(tear_down)
392 self.clean_processes()
394 super(LinuxNode, self).do_release()
396 def valid_connection(self, guid):
400 def clean_processes(self, killer = False):
401 self.info("Cleaning up processes")
405 cmd = ("sudo -S killall python tcpdump || /bin/true ; " +
406 "sudo -S killall python tcpdump || /bin/true ; " +
407 "sudo -S kill $(ps -N -T -o pid --no-heading | grep -v $PPID | sort) || /bin/true ; " +
408 "sudo -S killall -u root || /bin/true ; " +
409 "sudo -S killall -u root || /bin/true ; ")
412 cmd = ("sudo -S killall tcpdump || /bin/true ; " +
413 "sudo -S killall tcpdump || /bin/true ; " +
414 "sudo -S killall -u %s || /bin/true ; " % self.get("username") +
415 "sudo -S killall -u %s || /bin/true ; " % self.get("username"))
418 (out, err), proc = self.execute(cmd, retry = 1, with_lock = True)
420 def clean_home(self):
421 """ Cleans all NEPI related folders in the Linux host
423 self.info("Cleaning up home")
425 cmd = "cd %s ; find . -maxdepth 1 \( -name 'nepi-usr' -o -name 'nepi-exp' \) -execdir rm -rf {} + " % (
428 return self.execute(cmd, with_lock = True)
430 def clean_experiment(self):
431 """ Cleans all experiment related files in the Linux host.
432 It preserves NEPI files and folders that have a multi experiment
435 self.info("Cleaning up experiment files")
437 cmd = "cd %s ; find . -maxdepth 1 -name '%s' -execdir rm -rf {} + " % (
441 return self.execute(cmd, with_lock = True)
443 def execute(self, command,
451 err_on_timeout = True,
452 connect_timeout = 30,
453 strict_host_checking = False,
458 """ Notice that this invocation will block until the
459 execution finishes. If this is not the desired behavior,
460 use 'run' instead."""
463 (out, err), proc = execfuncs.lexec(command,
470 with self._node_lock:
471 (out, err), proc = sshfuncs.rexec(
473 host = self.get("hostname"),
474 user = self.get("username"),
475 port = self.get("port"),
479 identity = self.get("identity"),
480 server_key = self.get("serverKey"),
483 forward_x11 = forward_x11,
486 err_on_timeout = err_on_timeout,
487 connect_timeout = connect_timeout,
488 persistent = persistent,
490 strict_host_checking = strict_host_checking
493 (out, err), proc = sshfuncs.rexec(
495 host = self.get("hostname"),
496 user = self.get("username"),
497 port = self.get("port"),
501 identity = self.get("identity"),
502 server_key = self.get("serverKey"),
505 forward_x11 = forward_x11,
508 err_on_timeout = err_on_timeout,
509 connect_timeout = connect_timeout,
510 persistent = persistent,
512 strict_host_checking = strict_host_checking
515 return (out, err), proc
517 def run(self, command, home,
526 self.debug("Running command '%s'" % command)
529 (out, err), proc = execfuncs.lspawn(command, pidfile,
534 create_home = create_home,
538 with self._node_lock:
539 (out, err), proc = sshfuncs.rspawn(
543 create_home = create_home,
544 stdin = stdin if stdin is not None else '/dev/null',
545 stdout = stdout if stdout else '/dev/null',
546 stderr = stderr if stderr else '/dev/null',
548 host = self.get("hostname"),
549 user = self.get("username"),
550 port = self.get("port"),
552 identity = self.get("identity"),
553 server_key = self.get("serverKey"),
557 return (out, err), proc
559 def getpid(self, home, pidfile = "pidfile"):
561 pidtuple = execfuncs.lgetpid(os.path.join(home, pidfile))
563 with self._node_lock:
564 pidtuple = sshfuncs.rgetpid(
565 os.path.join(home, pidfile),
566 host = self.get("hostname"),
567 user = self.get("username"),
568 port = self.get("port"),
570 identity = self.get("identity"),
571 server_key = self.get("serverKey")
576 def status(self, pid, ppid):
578 status = execfuncs.lstatus(pid, ppid)
580 with self._node_lock:
581 status = sshfuncs.rstatus(
583 host = self.get("hostname"),
584 user = self.get("username"),
585 port = self.get("port"),
587 identity = self.get("identity"),
588 server_key = self.get("serverKey")
593 def kill(self, pid, ppid, sudo = False):
596 status = self.status(pid, ppid)
598 if status == sshfuncs.ProcStatus.RUNNING:
600 (out, err), proc = execfuncs.lkill(pid, ppid, sudo)
602 with self._node_lock:
603 (out, err), proc = sshfuncs.rkill(
605 host = self.get("hostname"),
606 user = self.get("username"),
607 port = self.get("port"),
610 identity = self.get("identity"),
611 server_key = self.get("serverKey")
614 return (out, err), proc
616 def copy(self, src, dst):
618 (out, err), proc = execfuncs.lcopy(source, dest,
620 strict_host_checking = False)
622 with self._node_lock:
623 (out, err), proc = sshfuncs.rcopy(
625 port = self.get("port"),
626 identity = self.get("identity"),
627 server_key = self.get("serverKey"),
629 strict_host_checking = False)
631 return (out, err), proc
633 def upload(self, src, dst, text = False, overwrite = True):
634 """ Copy content to destination
636 src content to copy. Can be a local file, directory or a list of files
638 dst destination path on the remote host (remote is always self.host)
640 text src is text input, it must be stored into a temp file before uploading
642 # If source is a string input
644 if text and not os.path.isfile(src):
645 # src is text input that should be uploaded as file
646 # create a temporal file with the content to upload
647 f = tempfile.NamedTemporaryFile(delete=False)
652 # If dst files should not be overwritten, check that the files do not
654 if overwrite == False:
655 src = self.filter_existing_files(src, dst)
657 return ("", ""), None
659 if not self.localhost:
660 # Build destination as <user>@<server>:<path>
661 dst = "%s@%s:%s" % (self.get("username"), self.get("hostname"), dst)
663 result = self.copy(src, dst)
671 def download(self, src, dst):
672 if not self.localhost:
673 # Build destination as <user>@<server>:<path>
674 src = "%s@%s:%s" % (self.get("username"), self.get("hostname"), src)
675 return self.copy(src, dst)
677 def install_packages_command(self, packages):
680 command = rpmfuncs.install_packages_command(self.os, packages)
682 command = debfuncs.install_packages_command(self.os, packages)
684 msg = "Error installing packages ( OS not known ) "
685 self.error(msg, self.os)
686 raise RuntimeError, msg
690 def install_packages(self, packages, home, run_home = None):
691 """ Install packages in the Linux host.
693 'home' is the directory to upload the package installation script.
694 'run_home' is the directory from where to execute the script.
696 command = self.install_packages_command(packages)
698 run_home = run_home or home
700 (out, err), proc = self.run_and_wait(command, run_home,
701 shfile = os.path.join(home, "instpkg.sh"),
702 pidfile = "instpkg_pidfile",
703 ecodefile = "instpkg_exitcode",
704 stdout = "instpkg_stdout",
705 stderr = "instpkg_stderr",
707 raise_on_error = True)
709 return (out, err), proc
711 def remove_packages(self, packages, home, run_home = None):
712 """ Uninstall packages from the Linux host.
714 'home' is the directory to upload the package un-installation script.
715 'run_home' is the directory from where to execute the script.
718 command = rpmfuncs.remove_packages_command(self.os, packages)
720 command = debfuncs.remove_packages_command(self.os, packages)
722 msg = "Error removing packages ( OS not known ) "
724 raise RuntimeError, msg
726 run_home = run_home or home
728 (out, err), proc = self.run_and_wait(command, run_home,
729 shfile = os.path.join(home, "rmpkg.sh"),
730 pidfile = "rmpkg_pidfile",
731 ecodefile = "rmpkg_exitcode",
732 stdout = "rmpkg_stdout",
733 stderr = "rmpkg_stderr",
735 raise_on_error = True)
737 return (out, err), proc
739 def mkdir(self, path, clean = False):
743 return self.execute("mkdir -p %s" % path, with_lock = True)
745 def rmdir(self, path):
746 return self.execute("rm -rf %s" % path, with_lock = True)
748 def run_and_wait(self, command, home,
753 ecodefile = "exitcode",
759 raise_on_error = False):
761 Uploads the 'command' to a bash script in the host.
762 Then runs the script detached in background in the host, and
763 busy-waites until the script finishes executing.
766 if not shfile.startswith("/"):
767 shfile = os.path.join(home, shfile)
769 self.upload_command(command,
771 ecodefile = ecodefile,
773 overwrite = overwrite)
775 command = "bash %s" % shfile
776 # run command in background in remote host
777 (out, err), proc = self.run(command, home,
785 # check no errors occurred
787 msg = " Failed to run command '%s' " % command
788 self.error(msg, out, err)
790 raise RuntimeError, msg
792 # Wait for pid file to be generated
793 pid, ppid = self.wait_pid(
796 raise_on_error = raise_on_error)
798 # wait until command finishes to execute
799 self.wait_run(pid, ppid)
801 (eout, err), proc = self.check_errors(home,
802 ecodefile = ecodefile,
805 # Out is what was written in the stderr file
807 msg = " Failed to run command '%s' " % command
808 self.error(msg, eout, err)
811 raise RuntimeError, msg
813 (out, oerr), proc = self.check_output(home, stdout)
815 return (out, err), proc
817 def exitcode(self, home, ecodefile = "exitcode"):
819 Get the exit code of an application.
820 Returns an integer value with the exit code
822 (out, err), proc = self.check_output(home, ecodefile)
824 # Succeeded to open file, return exit code in the file
827 return int(out.strip())
829 # Error in the content of the file!
830 return ExitCode.CORRUPTFILE
832 # No such file or directory
833 if proc.returncode == 1:
834 return ExitCode.FILENOTFOUND
836 # Other error from 'cat'
837 return ExitCode.ERROR
839 def upload_command(self, command,
841 ecodefile = "exitcode",
844 """ Saves the command as a bash script file in the remote host, and
845 forces to save the exit code of the command execution to the ecodefile
848 if not (command.strip().endswith(";") or command.strip().endswith("&")):
851 # The exit code of the command will be stored in ecodefile
852 command = " { %(command)s } ; echo $? > %(ecodefile)s ;" % {
854 'ecodefile': ecodefile,
858 environ = self.format_environment(env)
860 # Add environ to command
861 command = environ + command
863 return self.upload(command, shfile, text = True, overwrite = overwrite)
865 def format_environment(self, env, inline = False):
866 """ Formats the environment variables for a command to be executed
867 either as an inline command
868 (i.e. export PYTHONPATH=src/..; export LALAL= ..;python script.py) or
869 as a bash script (i.e. export PYTHONPATH=src/.. \n export LALA=.. \n)
871 if not env: return ""
873 # Remove extra white spaces
874 env = re.sub(r'\s+', ' ', env.strip())
876 sep = ";" if inline else "\n"
877 return sep.join(map(lambda e: " export %s" % e, env.split(" "))) + sep
879 def check_errors(self, home,
880 ecodefile = "exitcode",
882 """ Checks whether errors occurred while running a command.
883 It first checks the exit code for the command, and only if the
884 exit code is an error one it returns the error output.
890 # get exit code saved in the 'exitcode' file
891 ecode = self.exitcode(home, ecodefile)
893 if ecode in [ ExitCode.CORRUPTFILE, ExitCode.ERROR ]:
894 err = "Error retrieving exit code status from file %s/%s" % (home, ecodefile)
895 elif ecode > 0 or ecode == ExitCode.FILENOTFOUND:
896 # The process returned an error code or didn't exist.
897 # Check standard error.
898 (err, eerr), proc = self.check_output(home, stderr)
900 # If the stderr file was not found, assume nothing bad happened,
901 # and just ignore the error.
902 # (cat returns 1 for error "No such file or directory")
903 if ecode == ExitCode.FILENOTFOUND and proc.poll() == 1:
906 return ("", err), proc
908 def wait_pid(self, home, pidfile = "pidfile", raise_on_error = False):
909 """ Waits until the pid file for the command is generated,
910 and returns the pid and ppid of the process """
915 pidtuple = self.getpid(home = home, pidfile = pidfile)
924 msg = " Failed to get pid for pidfile %s/%s " % (
929 raise RuntimeError, msg
933 def wait_run(self, pid, ppid, trial = 0):
934 """ wait for a remote process to finish execution """
938 status = self.status(pid, ppid)
940 if status is ProcStatus.FINISHED:
942 elif status is not ProcStatus.RUNNING:
945 # If it takes more than 20 seconds to start, then
946 # asume something went wrong
950 # The app is running, just wait...
953 def check_output(self, home, filename):
954 """ Retrives content of file """
955 (out, err), proc = self.execute("cat %s" %
956 os.path.join(home, filename), retry = 1, with_lock = True)
957 return (out, err), proc
960 """ Checks if host is responsive
966 # The underlying SSH layer will sometimes return an empty
967 # output (even if the command was executed without errors).
968 # To work arround this, repeat the operation N times or
969 # until the result is not empty string
973 (out, err), proc = self.execute("echo 'ALIVE'",
978 if out.find("ALIVE") > -1:
981 trace = traceback.format_exc()
982 msg = "Unresponsive host. Error reaching host: %s " % trace
983 self.error(msg, out, err)
986 time.sleep(min(30.0, retrydelay))
989 if out.find("ALIVE") > -1:
992 msg = "Unresponsive host. Wrong answer. "
993 self.error(msg, out, err)
997 """ Retrieves host home directory
999 # The underlying SSH layer will sometimes return an empty
1000 # output (even if the command was executed without errors).
1001 # To work arround this, repeat the operation N times or
1002 # until the result is not empty string
1006 (out, err), proc = self.execute("echo ${HOME}",
1011 if out.strip() != "":
1012 self._home_dir = out.strip()
1015 trace = traceback.format_exc()
1016 msg = "Impossible to retrieve HOME directory" % trace
1017 self.error(msg, out, err)
1020 time.sleep(min(30.0, retrydelay))
1023 if not self._home_dir:
1024 msg = "Impossible to retrieve HOME directory"
1025 self.error(msg, out, err)
1026 raise RuntimeError, msg
1028 def filter_existing_files(self, src, dst):
1029 """ Removes files that already exist in the Linux host from src list
1031 # construct a dictionary with { dst: src }
1032 dests = dict(map(lambda x: ( os.path.join(dst, os.path.basename(x) ), x ),
1033 src.strip().split(" ") ) ) if src.strip().find(" ") != -1 else dict({dst: src})
1036 for d in dests.keys():
1037 command.append(" [ -f %(dst)s ] && echo '%(dst)s' " % {'dst' : d} )
1039 command = ";".join(command)
1041 (out, err), proc = self.execute(command, retry = 1, with_lock = True)
1043 for d in dests.keys():
1044 if out.find(d) > -1:
1050 return " ".join(dests.values())