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.Design)
154 username = Attribute("username", "Local account username",
155 flags = Flags.Credential)
157 port = Attribute("port", "SSH port", flags = Flags.Design)
159 home = Attribute("home",
160 "Experiment home directory to store all experiment related files",
161 flags = Flags.Design)
163 identity = Attribute("identity", "SSH identity file",
164 flags = Flags.Credential)
166 server_key = Attribute("serverKey", "Server public key",
167 flags = Flags.Design)
169 clean_home = Attribute("cleanHome", "Remove all nepi files and directories "
170 " from node home folder before starting experiment",
173 flags = Flags.Design)
175 clean_experiment = Attribute("cleanExperiment", "Remove all files and directories "
176 " from a previous same experiment, before the new experiment starts",
179 flags = Flags.Design)
181 clean_processes = Attribute("cleanProcesses",
182 "Kill all running processes before starting experiment",
185 flags = Flags.Design)
187 tear_down = Attribute("tearDown", "Bash script to be executed before " + \
188 "releasing the resource",
189 flags = Flags.Design)
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
302 (out, err), proc = self.execute("cat /etc/issue",
306 trace = traceback.format_exc()
307 msg = "Error detecting OS: %s " % trace
308 self.error(msg, out, err)
314 return self.os in [OSType.DEBIAN, OSType.UBUNTU]
318 return self.os in [OSType.FEDORA_12, OSType.FEDORA_14, OSType.FEDORA_8,
323 return self.get("hostname") in ['localhost', '127.0.0.7', '::1']
325 def do_provision(self):
326 # check if host is alive
327 if not self.is_alive():
328 msg = "Deploy failed. Unresponsive node %s" % self.get("hostname")
330 raise RuntimeError, msg
334 if self.get("cleanProcesses"):
335 self.clean_processes()
337 if self.get("cleanHome"):
340 if self.get("cleanExperiment"):
341 self.clean_experiment()
343 # Create shared directory structure
344 self.mkdir(self.lib_dir)
345 self.mkdir(self.bin_dir)
346 self.mkdir(self.src_dir)
347 self.mkdir(self.share_dir)
349 # Create experiment node home directory
350 self.mkdir(self.node_home)
352 super(LinuxNode, self).do_provision()
355 if self.state == ResourceState.NEW:
356 self.info("Deploying node")
360 # Node needs to wait until all associated interfaces are
361 # ready before it can finalize deployment
362 from nepi.resources.linux.interface import LinuxInterface
363 ifaces = self.get_connected(LinuxInterface.get_rtype())
365 if iface.state < ResourceState.READY:
366 self.ec.schedule(reschedule_delay, self.deploy)
369 super(LinuxNode, self).do_deploy()
371 def do_release(self):
372 rms = self.get_connected()
374 # Node needs to wait until all associated RMs are released
375 # before it can be released
376 if rm.state != ResourceState.RELEASED:
377 self.ec.schedule(reschedule_delay, self.release)
380 tear_down = self.get("tearDown")
382 self.execute(tear_down)
384 self.clean_processes()
386 super(LinuxNode, self).do_release()
388 def valid_connection(self, guid):
392 def clean_processes(self):
393 self.info("Cleaning up processes")
395 cmd = ("sudo -S killall tcpdump || /bin/true ; " +
396 "sudo -S kill $(ps aux | grep '[n]epi' | awk '{print $2}') || /bin/true ; " +
397 "sudo -S killall -u %s || /bin/true ; " % self.get("username"))
400 (out, err), proc = self.execute(cmd, retry = 1, with_lock = True)
402 def clean_home(self):
403 """ Cleans all NEPI related folders in the Linux host
405 self.info("Cleaning up home")
407 cmd = "cd %s ; find . -maxdepth 1 \( -name 'nepi-usr' -o -name 'nepi-exp' \) -execdir rm -rf {} + " % (
410 return self.execute(cmd, with_lock = True)
412 def clean_experiment(self):
413 """ Cleans all experiment related files in the Linux host.
414 It preserves NEPI files and folders that have a multi experiment
417 self.info("Cleaning up experiment files")
419 cmd = "cd %s ; find . -maxdepth 1 -name '%s' -execdir rm -rf {} + " % (
423 return self.execute(cmd, with_lock = True)
425 def execute(self, command,
431 connect_timeout = 30,
432 strict_host_checking = False,
437 """ Notice that this invocation will block until the
438 execution finishes. If this is not the desired behavior,
439 use 'run' instead."""
442 (out, err), proc = execfuncs.lexec(command,
443 user = self.get("username"), # still problem with localhost
448 # If the execute command is blocking, we don't want to keep
449 # the node lock. This lock is used to avoid race conditions
450 # when creating the ControlMaster sockets. A more elegant
451 # solution is needed.
452 with self._node_lock:
453 (out, err), proc = sshfuncs.rexec(
455 host = self.get("hostname"),
456 user = self.get("username"),
457 port = self.get("port"),
460 identity = self.get("identity"),
461 server_key = self.get("serverKey"),
464 forward_x11 = forward_x11,
466 connect_timeout = connect_timeout,
467 persistent = persistent,
469 strict_host_checking = strict_host_checking
472 (out, err), proc = sshfuncs.rexec(
474 host = self.get("hostname"),
475 user = self.get("username"),
476 port = self.get("port"),
479 identity = self.get("identity"),
480 server_key = self.get("serverKey"),
483 forward_x11 = forward_x11,
485 connect_timeout = connect_timeout,
486 persistent = persistent,
488 strict_host_checking = strict_host_checking
491 return (out, err), proc
493 def run(self, command, home,
502 self.debug("Running command '%s'" % command)
505 (out, err), proc = execfuncs.lspawn(command, pidfile,
510 create_home = create_home,
514 with self._node_lock:
515 (out, err), proc = sshfuncs.rspawn(
519 create_home = create_home,
520 stdin = stdin if stdin is not None else '/dev/null',
521 stdout = stdout if stdout else '/dev/null',
522 stderr = stderr if stderr else '/dev/null',
524 host = self.get("hostname"),
525 user = self.get("username"),
526 port = self.get("port"),
528 identity = self.get("identity"),
529 server_key = self.get("serverKey"),
533 return (out, err), proc
535 def getpid(self, home, pidfile = "pidfile"):
537 pidtuple = execfuncs.lgetpid(os.path.join(home, pidfile))
539 with self._node_lock:
540 pidtuple = sshfuncs.rgetpid(
541 os.path.join(home, pidfile),
542 host = self.get("hostname"),
543 user = self.get("username"),
544 port = self.get("port"),
546 identity = self.get("identity"),
547 server_key = self.get("serverKey")
552 def status(self, pid, ppid):
554 status = execfuncs.lstatus(pid, ppid)
556 with self._node_lock:
557 status = sshfuncs.rstatus(
559 host = self.get("hostname"),
560 user = self.get("username"),
561 port = self.get("port"),
563 identity = self.get("identity"),
564 server_key = self.get("serverKey")
569 def kill(self, pid, ppid, sudo = False):
572 status = self.status(pid, ppid)
574 if status == sshfuncs.ProcStatus.RUNNING:
576 (out, err), proc = execfuncs.lkill(pid, ppid, sudo)
578 with self._node_lock:
579 (out, err), proc = sshfuncs.rkill(
581 host = self.get("hostname"),
582 user = self.get("username"),
583 port = self.get("port"),
586 identity = self.get("identity"),
587 server_key = self.get("serverKey")
590 return (out, err), proc
592 def copy(self, src, dst):
594 (out, err), proc = execfuncs.lcopy(source, dest,
596 strict_host_checking = False)
598 (out, err), proc = sshfuncs.rcopy(
600 port = self.get("port"),
601 identity = self.get("identity"),
602 server_key = self.get("serverKey"),
604 strict_host_checking = False)
606 return (out, err), proc
608 def upload(self, src, dst, text = False, overwrite = True):
609 """ Copy content to destination
611 src content to copy. Can be a local file, directory or a list of files
613 dst destination path on the remote host (remote is always self.host)
615 text src is text input, it must be stored into a temp file before uploading
617 # If source is a string input
619 if text and not os.path.isfile(src):
620 # src is text input that should be uploaded as file
621 # create a temporal file with the content to upload
622 f = tempfile.NamedTemporaryFile(delete=False)
627 # If dst files should not be overwritten, check that the files do not
629 if overwrite == False:
630 src = self.filter_existing_files(src, dst)
632 return ("", ""), None
634 if not self.localhost:
635 # Build destination as <user>@<server>:<path>
636 dst = "%s@%s:%s" % (self.get("username"), self.get("hostname"), dst)
638 result = self.copy(src, dst)
646 def download(self, src, dst):
647 if not self.localhost:
648 # Build destination as <user>@<server>:<path>
649 src = "%s@%s:%s" % (self.get("username"), self.get("hostname"), src)
650 return self.copy(src, dst)
652 def install_packages_command(self, packages):
655 command = rpmfuncs.install_packages_command(self.os, packages)
657 command = debfuncs.install_packages_command(self.os, packages)
659 msg = "Error installing packages ( OS not known ) "
660 self.error(msg, self.os)
661 raise RuntimeError, msg
665 def install_packages(self, packages, home, run_home = None):
666 """ Install packages in the Linux host.
668 'home' is the directory to upload the package installation script.
669 'run_home' is the directory from where to execute the script.
671 command = self.install_packages_command(packages)
673 run_home = run_home or home
675 (out, err), proc = self.run_and_wait(command, run_home,
676 shfile = os.path.join(home, "instpkg.sh"),
677 pidfile = "instpkg_pidfile",
678 ecodefile = "instpkg_exitcode",
679 stdout = "instpkg_stdout",
680 stderr = "instpkg_stderr",
682 raise_on_error = True)
684 return (out, err), proc
686 def remove_packages(self, packages, home, run_home = None):
687 """ Uninstall packages from the Linux host.
689 'home' is the directory to upload the package un-installation script.
690 'run_home' is the directory from where to execute the script.
693 command = rpmfuncs.remove_packages_command(self.os, packages)
695 command = debfuncs.remove_packages_command(self.os, packages)
697 msg = "Error removing packages ( OS not known ) "
699 raise RuntimeError, msg
701 run_home = run_home or home
703 (out, err), proc = self.run_and_wait(command, run_home,
704 shfile = os.path.join(home, "rmpkg.sh"),
705 pidfile = "rmpkg_pidfile",
706 ecodefile = "rmpkg_exitcode",
707 stdout = "rmpkg_stdout",
708 stderr = "rmpkg_stderr",
710 raise_on_error = True)
712 return (out, err), proc
714 def mkdir(self, path, clean = False):
718 return self.execute("mkdir -p %s" % path, with_lock = True)
720 def rmdir(self, path):
721 return self.execute("rm -rf %s" % path, with_lock = True)
723 def run_and_wait(self, command, home,
728 ecodefile = "exitcode",
734 raise_on_error = False):
736 Uploads the 'command' to a bash script in the host.
737 Then runs the script detached in background in the host, and
738 busy-waites until the script finishes executing.
741 if not shfile.startswith("/"):
742 shfile = os.path.join(home, shfile)
744 self.upload_command(command,
746 ecodefile = ecodefile,
748 overwrite = overwrite)
750 command = "bash %s" % shfile
751 # run command in background in remote host
752 (out, err), proc = self.run(command, home,
760 # check no errors occurred
762 msg = " Failed to run command '%s' " % command
763 self.error(msg, out, err)
765 raise RuntimeError, msg
767 # Wait for pid file to be generated
768 pid, ppid = self.wait_pid(
771 raise_on_error = raise_on_error)
773 # wait until command finishes to execute
774 self.wait_run(pid, ppid)
776 (eout, err), proc = self.check_errors(home,
777 ecodefile = ecodefile,
780 # Out is what was written in the stderr file
782 msg = " Failed to run command '%s' " % command
783 self.error(msg, eout, err)
786 raise RuntimeError, msg
788 (out, oerr), proc = self.check_output(home, stdout)
790 return (out, err), proc
792 def exitcode(self, home, ecodefile = "exitcode"):
794 Get the exit code of an application.
795 Returns an integer value with the exit code
797 (out, err), proc = self.check_output(home, ecodefile)
799 # Succeeded to open file, return exit code in the file
802 return int(out.strip())
804 # Error in the content of the file!
805 return ExitCode.CORRUPTFILE
807 # No such file or directory
808 if proc.returncode == 1:
809 return ExitCode.FILENOTFOUND
811 # Other error from 'cat'
812 return ExitCode.ERROR
814 def upload_command(self, command,
816 ecodefile = "exitcode",
819 """ Saves the command as a bash script file in the remote host, and
820 forces to save the exit code of the command execution to the ecodefile
823 if not (command.strip().endswith(";") or command.strip().endswith("&")):
826 # The exit code of the command will be stored in ecodefile
827 command = " { %(command)s } ; echo $? > %(ecodefile)s ;" % {
829 'ecodefile': ecodefile,
833 environ = self.format_environment(env)
835 # Add environ to command
836 command = environ + command
838 return self.upload(command, shfile, text = True, overwrite = overwrite)
840 def format_environment(self, env, inline = False):
841 """ Formats the environment variables for a command to be executed
842 either as an inline command
843 (i.e. export PYTHONPATH=src/..; export LALAL= ..;python script.py) or
844 as a bash script (i.e. export PYTHONPATH=src/.. \n export LALA=.. \n)
846 if not env: return ""
848 # Remove extra white spaces
849 env = re.sub(r'\s+', ' ', env.strip())
851 sep = ";" if inline else "\n"
852 return sep.join(map(lambda e: " export %s" % e, env.split(" "))) + sep
854 def check_errors(self, home,
855 ecodefile = "exitcode",
857 """ Checks whether errors occurred while running a command.
858 It first checks the exit code for the command, and only if the
859 exit code is an error one it returns the error output.
865 # get exit code saved in the 'exitcode' file
866 ecode = self.exitcode(home, ecodefile)
868 if ecode in [ ExitCode.CORRUPTFILE, ExitCode.ERROR ]:
869 err = "Error retrieving exit code status from file %s/%s" % (home, ecodefile)
870 elif ecode > 0 or ecode == ExitCode.FILENOTFOUND:
871 # The process returned an error code or didn't exist.
872 # Check standard error.
873 (err, eerr), proc = self.check_output(home, stderr)
875 # If the stderr file was not found, assume nothing bad happened,
876 # and just ignore the error.
877 # (cat returns 1 for error "No such file or directory")
878 if ecode == ExitCode.FILENOTFOUND and proc.poll() == 1:
881 return ("", err), proc
883 def wait_pid(self, home, pidfile = "pidfile", raise_on_error = False):
884 """ Waits until the pid file for the command is generated,
885 and returns the pid and ppid of the process """
890 pidtuple = self.getpid(home = home, pidfile = pidfile)
899 msg = " Failed to get pid for pidfile %s/%s " % (
904 raise RuntimeError, msg
908 def wait_run(self, pid, ppid, trial = 0):
909 """ wait for a remote process to finish execution """
913 status = self.status(pid, ppid)
915 if status is ProcStatus.FINISHED:
917 elif status is not ProcStatus.RUNNING:
920 # If it takes more than 20 seconds to start, then
921 # asume something went wrong
925 # The app is running, just wait...
928 def check_output(self, home, filename):
929 """ Retrives content of file """
930 (out, err), proc = self.execute("cat %s" %
931 os.path.join(home, filename), retry = 1, with_lock = True)
932 return (out, err), proc
935 """ Checks if host is responsive
941 msg = "Unresponsive host. Wrong answer. "
943 # The underlying SSH layer will sometimes return an empty
944 # output (even if the command was executed without errors).
945 # To work arround this, repeat the operation N times or
946 # until the result is not empty string
948 (out, err), proc = self.execute("echo 'ALIVE'",
952 if out.find("ALIVE") > -1:
955 trace = traceback.format_exc()
956 msg = "Unresponsive host. Error reaching host: %s " % trace
958 self.error(msg, out, err)
962 """ Retrieves host home directory
964 # The underlying SSH layer will sometimes return an empty
965 # output (even if the command was executed without errors).
966 # To work arround this, repeat the operation N times or
967 # until the result is not empty string
968 msg = "Impossible to retrieve HOME directory"
970 (out, err), proc = self.execute("echo ${HOME}",
974 if out.strip() != "":
975 self._home_dir = out.strip()
977 trace = traceback.format_exc()
978 msg = "Impossible to retrieve HOME directory %s" % trace
980 if not self._home_dir:
982 raise RuntimeError, msg
984 def filter_existing_files(self, src, dst):
985 """ Removes files that already exist in the Linux host from src list
987 # construct a dictionary with { dst: src }
988 dests = dict(map(lambda x: ( os.path.join(dst, os.path.basename(x) ), x ),
989 src.strip().split(" ") ) ) if src.strip().find(" ") != -1 else dict({dst: src})
992 for d in dests.keys():
993 command.append(" [ -f %(dst)s ] && echo '%(dst)s' " % {'dst' : d} )
995 command = ";".join(command)
997 (out, err), proc = self.execute(command, retry = 1, with_lock = True)
999 for d in dests.keys():
1000 if out.find(d) > -1:
1006 return " ".join(dests.values())