src/nepi/resources/linux/ns3/ns3simulation.py

   1 #
   2 #    NEPI, a framework to manage network experiments
   3 #    Copyright (C) 2014 INRIA
   4 #
   5 #    This program is free software: you can redistribute it and/or modify
   6 #    it under the terms of the GNU General Public License version 2 as
   7 #    published by the Free Software Foundation;
   8 #
   9 #    This program is distributed in the hope that it will be useful,
  10 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 #    GNU General Public License for more details.
  13 #
  14 #    You should have received a copy of the GNU General Public License
  15 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 #
  17 # Author: Alina Quereilhac <alina.quereilhac@inria.fr>
  18
  19 from nepi.execution.attribute import Attribute, Flags, Types
  20 from nepi.execution.trace import Trace, TraceAttr
  21 from nepi.execution.resource import ResourceManager, clsinit_copy, \
  22         ResourceState, ResourceFactory
  23 from nepi.resources.linux.application import LinuxApplication
  24 from nepi.util.timefuncs import tnow, tdiffsec
  25 from nepi.resources.ns3.ns3simulation import NS3Simulation
  26 from nepi.resources.ns3.ns3wrapper import SIMULATOR_UUID, GLOBAL_VALUE_UUID, \
  27         IPV4_GLOBAL_ROUTING_HELPER_UUID
  28 from nepi.resources.linux.ns3.ns3client import LinuxNS3Client
  29
  30 import os
  31 import time
  32 import threading
  33
  34 @clsinit_copy
  35 class LinuxNS3Simulation(LinuxApplication, NS3Simulation):
  36     _rtype = "linux::ns3::Simulation"
  37
  38     @classmethod
  39     def _register_attributes(cls):
  40         impl_type = Attribute("simulatorImplementationType",
  41                 "The object class to use as the simulator implementation",
  42             allowed = ["ns3::DefaultSimulatorImpl", "ns3::RealtimeSimulatorImpl"],
  43             default = "ns3::DefaultSimulatorImpl",
  44             type = Types.Enumerate,
  45             flags = Flags.Design)
  46
  47         sched_type = Attribute("schedulerType",
  48                 "The object class to use as the scheduler implementation",
  49                 allowed = ["ns3::MapScheduler",
  50                             "ns3::ListScheduler",
  51                             "ns3::HeapScheduler",
  52                             "ns3::MapScheduler",
  53                             "ns3::CalendarScheduler"
  54                     ],
  55             default = "ns3::MapScheduler",
  56             type = Types.Enumerate,
  57             flags = Flags.Design)
  58
  59         check_sum = Attribute("checksumEnabled",
  60                 "A global switch to enable all checksums for all protocols",
  61             default = False,
  62             type = Types.Bool,
  63             flags = Flags.Design)
  64
  65         ns_log = Attribute("nsLog",
  66             "NS_LOG environment variable. " \
  67                     " Will only generate output if ns-3 is compiled in DEBUG mode. ",
  68             flags = Flags.Design)
  69
  70         verbose = Attribute("verbose",
  71             "True to output debugging info from the ns3 client-server communication",
  72             type = Types.Bool,
  73             flags = Flags.Design)
  74
  75         enable_dump = Attribute("enableDump",
  76             "Enable dumping the remote executed ns-3 commands to a script "
  77             "in order to later reproduce and debug the experiment",
  78             type = Types.Bool,
  79             default = False,
  80             flags = Flags.Design)
  81
  82         build_mode = Attribute("buildMode",
  83             "Mode used to build ns-3 with waf. One if: debug, release, oprimized ",
  84             default = "optimized",
  85             allowed = ["debug", "release", "optimized"],
  86             type = Types.Enumerate,
  87             flags = Flags.Design)
  88
  89         ns3_version = Attribute("ns3Version",
  90             "Version of ns-3 to install from nsam repo",
  91             default = "ns-3.20",
  92             #default = "ns-3-dev",
  93             flags = Flags.Design)
  94
  95         pybindgen_version = Attribute("pybindgenVersion",
  96             "Version of pybindgen to install from bazar repo",
  97             default = "868",
  98             #default = "876",
  99             flags = Flags.Design)
 100
 101         dce_version = Attribute("dceVersion",
 102             "Version of dce to install from nsam repo (tag branch for repo)",
 103             #default = "dce-1.3",
 104             default = "dce-dev",
 105             flags = Flags.Design)
 106
 107         populate_routing_tables = Attribute("populateRoutingTables",
 108             "Invokes  Ipv4GlobalRoutingHelper.PopulateRoutingTables() ",
 109             default = False,
 110             type = Types.Bool,
 111             flags = Flags.Design)
 112
 113         stoptime = Attribute("StopTime",
 114             "Time at which the simulation will stop",
 115             flags = Flags.Design)
 116
 117         cls._register_attribute(impl_type)
 118         cls._register_attribute(sched_type)
 119         cls._register_attribute(check_sum)
 120         cls._register_attribute(ns_log)
 121         cls._register_attribute(enable_dump)
 122         cls._register_attribute(verbose)
 123         cls._register_attribute(build_mode)
 124         cls._register_attribute(ns3_version)
 125         cls._register_attribute(pybindgen_version)
 126         cls._register_attribute(dce_version)
 127         cls._register_attribute(populate_routing_tables)
 128         cls._register_attribute(stoptime)
 129
 130     def __init__(self, ec, guid):
 131         LinuxApplication.__init__(self, ec, guid)
 132         NS3Simulation.__init__(self)
 133
 134         self._client = None
 135         self._home = "ns3-simu-%s" % self.guid
 136         self._socket_name = "ns3-%s.sock" % os.urandom(4).encode('hex')
 137         self._enable_dce = None
 138         self._dce_helper = None
 139
 140     @property
 141     def socket_name(self):
 142         return self._socket_name
 143
 144     @property
 145     def remote_socket(self):
 146         return os.path.join(self.run_home, self.socket_name)
 147
 148     def trace(self, name, attr = TraceAttr.ALL, block = 512, offset = 0):
 149         # stout needs to get flushed on the ns-3 server side, else we will
 150         # get an empty stream. We try twice to retrieve the stream
 151         # if we get empty stdout since the stream might not be
 152         # flushed immediately.
 153         if name.endswith("stdout"):
 154             self._client.flush()
 155             result = LinuxApplication.trace(self, name, attr, block, offset)
 156             if result:
 157                 return result
 158             # Let the stream be flushed
 159             time.sleep(1)
 160
 161         return LinuxApplication.trace(self, name, attr, block, offset)
 162
 163     def upload_sources(self):
 164         self.node.mkdir(os.path.join(self.node.src_dir, "ns3wrapper"))
 165
 166         # upload ns3 wrapper python script
 167         ns3_wrapper = os.path.join(os.path.dirname(__file__), "..", "..", "ns3",
 168                 "ns3wrapper.py")
 169
 170         self.node.upload(ns3_wrapper,
 171                 os.path.join(self.node.src_dir, "ns3wrapper", "ns3wrapper.py"),
 172                 overwrite = False)
 173
 174         # upload ns3 wrapper debug python script
 175         ns3_wrapper_debug = os.path.join(os.path.dirname(__file__), "..", "..", "ns3",
 176                 "ns3wrapper_debug.py")
 177
 178         self.node.upload(ns3_wrapper_debug,
 179                 os.path.join(self.node.src_dir, "ns3wrapper", "ns3wrapper_debug.py"),
 180                 overwrite = False)
 181
 182         # upload ns3_server python script
 183         ns3_server = os.path.join(os.path.dirname(__file__), "..", "..", "ns3",
 184                 "ns3server.py")
 185
 186         self.node.upload(ns3_server,
 187                 os.path.join(self.node.src_dir, "ns3wrapper", "ns3server.py"),
 188                 overwrite = False)
 189
 190         if self.node.use_rpm:
 191             # upload pygccxml sources
 192             pygccxml_tar = os.path.join(os.path.dirname(__file__), "dependencies",
 193                     "%s.tar.gz" % self.pygccxml_version)
 194
 195             self.node.upload(pygccxml_tar,
 196                     os.path.join(self.node.src_dir, "%s.tar.gz" % self.pygccxml_version),
 197                     overwrite = False)
 198
 199         # Upload user defined ns-3 sources
 200         self.node.mkdir(os.path.join(self.node.src_dir, "ns-3"))
 201         src_dir = os.path.join(self.node.src_dir, "ns-3")
 202
 203         super(LinuxNS3Simulation, self).upload_sources(src_dir = src_dir)
 204
 205     def upload_extra_sources(self, sources = None, src_dir = None):
 206         return super(LinuxNS3Simulation, self).upload_sources(
 207                 sources = sources,
 208                 src_dir = src_dir)
 209
 210     def upload_start_command(self):
 211         command = self.get("command")
 212         env = self.get("env")
 213
 214         # We want to make sure the ccnd is running
 215         # before the experiment starts.
 216         # Run the command as a bash script in background,
 217         # in the host ( but wait until the command has
 218         # finished to continue )
 219         env = self.replace_paths(env)
 220         command = self.replace_paths(command)
 221
 222         shfile = os.path.join(self.app_home, "start.sh")
 223         self.node.upload_command(command,
 224                     shfile = shfile,
 225                     env = env,
 226                     overwrite = True)
 227
 228         # Run the ns3wrapper
 229         self._run_in_background()
 230
 231         # Wait until the remote socket is created
 232         self.wait_remote_socket()
 233
 234     def configure(self):
 235         if self.has_changed("simulatorImplementationType"):
 236             simu_type = self.get("simulatorImplementationType")
 237             stype = self.create("StringValue", simu_type)
 238             self.invoke(GLOBAL_VALUE_UUID, "Bind", "SimulatorImplementationType", stype)
 239
 240         if self.has_changed("checksumEnabled"):
 241             check_sum = self.get("checksumEnabled")
 242             btrue = self.create("BooleanValue", check_sum)
 243             self.invoke(GLOBAL_VALUE_UUID, "Bind", "ChecksumEnabled", btrue)
 244
 245         if self.has_changed("schedulerType"):
 246             sched_type = self.get("schedulerType")
 247             stype = self.create("StringValue", sched_type)
 248             self.invoke(GLOBAL_VALUE_UUID, "Bind", "SchedulerType", btrue)
 249
 250     def do_deploy(self):
 251         if not self.node or self.node.state < ResourceState.READY:
 252             self.debug("---- RESCHEDULING DEPLOY ---- node state %s " % self.node.state )
 253
 254             # ccnd needs to wait until node is deployed and running
 255             self.ec.schedule(self.reschedule_delay, self.deploy)
 256         else:
 257             if not self.get("command"):
 258                 self.set("command", self._start_command)
 259
 260             if not self.get("depends"):
 261                 self.set("depends", self._dependencies)
 262
 263             if self.get("sources"):
 264                 sources = self.get("sources")
 265                 source = sources.split(" ")[0]
 266                 basename = os.path.basename(source)
 267                 version = ( basename.strip().replace(".tar.gz", "")
 268                     .replace(".tar","")
 269                     .replace(".gz","")
 270                     .replace(".zip","") )
 271
 272                 self.set("ns3Version", version)
 273                 self.set("sources", source)
 274
 275             if not self.get("build"):
 276                 self.set("build", self._build)
 277
 278             if not self.get("install"):
 279                 self.set("install", self._install)
 280
 281             if not self.get("env"):
 282                 self.set("env", self._environment)
 283
 284             self.do_discover()
 285             self.do_provision()
 286
 287             # Create client
 288             self._client = LinuxNS3Client(self)
 289
 290             self.configure()
 291
 292             self.set_ready()
 293
 294     def do_start(self):
 295         """ Starts simulation execution
 296
 297         """
 298         self.info("Starting")
 299
 300         if self.state == ResourceState.READY:
 301             if self.get("populateRoutingTables") == True:
 302                 self.invoke(IPV4_GLOBAL_ROUTING_HELPER_UUID, "PopulateRoutingTables")
 303
 304             time = self.get("StopTime")
 305             if time:
 306                 self._client.stop(time=time)
 307
 308             self._client.start()
 309
 310             self.set_started()
 311         else:
 312             msg = " Failed to execute command '%s'" % command
 313             self.error(msg, out, err)
 314             raise RuntimeError, msg
 315
 316     def do_stop(self):
 317         """ Stops simulation execution
 318
 319         """
 320         if self.state == ResourceState.STARTED:
 321             if not self.get("StopTime"):
 322                 self._client.stop()
 323             self.set_stopped()
 324
 325     def do_release(self):
 326         self.info("Releasing resource")
 327
 328         tear_down = self.get("tearDown")
 329         if tear_down:
 330             self.node.execute(tear_down)
 331
 332         self.do_stop()
 333         self._client.shutdown()
 334         LinuxApplication.do_stop(self)
 335
 336         super(LinuxApplication, self).do_release()
 337
 338     @property
 339     def enable_dce(self):
 340         if self._enable_dce is None:
 341             from nepi.resources.ns3.ns3dceapplication import NS3BaseDceApplication
 342             rclass = ResourceFactory.get_resource_type(
 343                     NS3BaseDceApplication.get_rtype())
 344
 345             self._enable_dce = False
 346             for guid in self.ec.resources:
 347                 rm = self.ec.get_resource(guid)
 348                 if isinstance(rm, rclass):
 349                     self._enable_dce = True
 350
 351                     from nepi.resources.ns3.ns3dcehelper import NS3DceHelper
 352                     self._dce_helper = NS3DceHelper(self)
 353                     break
 354
 355         return self._enable_dce
 356
 357     @property
 358     def dce_helper(self):
 359         return self._dce_helper
 360
 361     @property
 362     def _start_command(self):
 363         command = []
 364
 365         command.append("PYTHONPATH=$PYTHONPATH:${SRC}/ns3wrapper/")
 366
 367         command.append("python ${SRC}/ns3wrapper/ns3server.py -S %s" % \
 368                 os.path.basename(self.remote_socket) )
 369
 370         ns_log = self.get("nsLog")
 371         if ns_log:
 372             command.append("-L '%s'" % ns_log)
 373
 374         if self.get("enableDump"):
 375             command.append("-D")
 376
 377         if self.get("verbose"):
 378             command.append("-v")
 379
 380         command = " ".join(command)
 381         return command
 382
 383     @property
 384     def _dependencies(self):
 385         if self.node.use_rpm:
 386             return ( " gcc gcc-c++ python python-devel mercurial bzr tcpdump socat gccxml unzip")
 387         elif self.node.use_deb:
 388             return ( " gcc g++ python python-dev mercurial bzr tcpdump socat gccxml python-pygccxml unzip")
 389         return ""
 390
 391     @property
 392     def ns3_repo(self):
 393         return "http://code.nsnam.org"
 394
 395     @property
 396     def pygccxml_version(self):
 397         return "pygccxml-1.0.0"
 398
 399     @property
 400     def dce_repo(self):
 401         return "http://code.nsnam.org/ns-3-dce"
 402         #eturn "http://code.nsnam.org/epmancini/ns-3-dce"
 403
 404     @property
 405     def dce_version(self):
 406         dce_version = self.get("dceVersion")
 407         return dce_version or "dce-dev"
 408
 409     @property
 410     def ns3_build_location(self):
 411         location = "${BIN}/ns-3/%(ns3_version)s%(dce_version)s/%(build_mode)s/build" \
 412                     % {
 413                         "ns3_version": self.get("ns3Version"),
 414                         "dce_version": "-%s" % self.get("dceVersion") \
 415                                 if self.enable_dce else "",
 416                         "build_mode": self.get("buildMode"),
 417                       }
 418
 419         return location
 420
 421
 422     @property
 423     def ns3_src_location(self):
 424         location = "${SRC}/ns-3/%(ns3_version)s" \
 425                     % {
 426                         "ns3_version": self.get("ns3Version"),
 427                       }
 428
 429         return location
 430
 431     @property
 432     def dce_src_location(self):
 433         location = "${SRC}/ns-3-dce/%(dce_version)s" \
 434                    % {
 435                         "dce_version": self.get("dceVersion"),
 436                      }
 437
 438         return location
 439
 440     @property
 441     def _clone_ns3_command(self):
 442         source = self.get("sources")
 443
 444         if not source:
 445             clone_ns3_cmd = "hg clone %(ns3_repo)s/%(ns3_version)s %(ns3_src)s" \
 446                     % {
 447                         "ns3_version": self.get("ns3Version"),
 448                         "ns3_repo": self.ns3_repo,
 449                         "ns3_src": self.ns3_src_location,
 450                       }
 451         else:
 452             if source.find(".tar.gz") > -1:
 453                 clone_ns3_cmd = (
 454                             "tar xzf ${SRC}/ns-3/%(basename)s "
 455                             " --strip-components=1 -C %(ns3_src)s"
 456                             ) % {
 457                                 "basename": os.path.basename(source),
 458                                 "ns3_src": self.ns3_src_location,
 459                                 }
 460             elif source.find(".tar") > -1:
 461                 clone_ns3_cmd = (
 462                             "tar xf ${SRC}/ns-3/%(basename)s "
 463                             " --strip-components=1 -C %(ns3_src)s"
 464                             ) % {
 465                                 "basename": os.path.basename(source),
 466                                 "ns3_src": self.ns3_src_location,
 467                                 }
 468             elif source.find(".zip") > -1:
 469                 basename = os.path.basename(source)
 470                 bare_basename = basename.replace(".zip", "")
 471
 472                 clone_ns3_cmd = (
 473                             "unzip ${SRC}/ns-3/%(basename)s && "
 474                             "mv ${SRC}/ns-3/%(bare_basename)s %(ns3_src)s"
 475                             ) % {
 476                                 "bare_basename": basename_name,
 477                                 "basename": basename,
 478                                 "ns3_src": self.ns3_src_location,
 479                                 }
 480
 481         return clone_ns3_cmd
 482
 483     @property
 484     def _clone_dce_command(self):
 485         clone_dce_cmd = " echo 'DCE will not be built' "
 486
 487         if self.enable_dce:
 488             dce_version = self.dce_version
 489             dce_tag = ""
 490             if dce_version != "dce-dev":
 491                 dce_tag = "-r %s" % dce_version
 492
 493             clone_dce_cmd = (
 494                         # DCE installation
 495                         # Test if dce is alredy cloned
 496                         " ( "
 497                         "  ( "
 498                         "    ( test -d %(dce_src)s ) "
 499                         "   && echo 'dce binaries found, nothing to do'"
 500                         "  ) "
 501                         " ) "
 502                         "  || "
 503                         # Get dce source code
 504                         " ( "
 505                         "   mkdir -p %(dce_src)s && "
 506                         "   hg clone %(dce_repo)s %(dce_tag)s %(dce_src)s"
 507                         " ) "
 508                      ) % {
 509                             "dce_repo": self.dce_repo,
 510                             "dce_tag": dce_tag,
 511                             "dce_src": self.dce_src_location,
 512                          }
 513
 514         return clone_dce_cmd
 515
 516     @property
 517     def _build(self):
 518         # If the user defined local sources for ns-3, we uncompress the sources
 519         # on the remote sources directory. Else we clone ns-3 from the official repo.
 520         clone_ns3_cmd = self._clone_ns3_command
 521         clone_dce_cmd = self._clone_dce_command
 522
 523         ns3_build_cmd = (
 524                 # NS3 installation
 525                 "( "
 526                 " ( "
 527                 # Test if ns-3 is alredy cloned
 528                 "  ((( test -d %(ns3_src)s ) || "
 529                 "    ( test -d ${NS3BINDINGS:='None'} && test -d ${NS3LIBRARIES:='None'})) "
 530                 "  && echo 'ns-3 binaries found, nothing to do' )"
 531                 " ) "
 532                 "  || "
 533                 # If not, install ns-3 and its dependencies
 534                 " (   "
 535                 # Install pygccxml
 536                 "   (   "
 537                 "     ( "
 538                 "       python -c 'import pygccxml' && "
 539                 "       echo 'pygccxml not found' "
 540                 "     ) "
 541                 "      || "
 542                 "     ( "
 543                 "       tar xf ${SRC}/%(pygccxml_version)s.tar.gz -C ${SRC} && "
 544                 "       cd ${SRC}/%(pygccxml_version)s && "
 545                 "       python setup.py build && "
 546                 "       sudo -S python setup.py install "
 547                 "     ) "
 548                 "   ) "
 549                 # Install pybindgen
 550                 "  && "
 551                 "   (   "
 552                 "     ( "
 553                 "       test -d ${SRC}/pybindgen/%(pybindgen_version)s && "
 554                 "       echo 'binaries found, nothing to do' "
 555                 "     ) "
 556                 "      || "
 557                 # If not, clone and build
 558                 "      ( cd ${SRC} && "
 559                 "        mkdir -p ${SRC}/pybindgen && "
 560                 "        bzr checkout lp:pybindgen -r %(pybindgen_version)s ${SRC}/pybindgen/%(pybindgen_version)s && "
 561                 "        cd ${SRC}/pybindgen/%(pybindgen_version)s && "
 562                 "        ./waf configure && "
 563                 "        ./waf "
 564                 "      ) "
 565                 "   ) "
 566                 " && "
 567                 # Get ns-3 source code
 568                 "  ( "
 569                 "     mkdir -p %(ns3_src)s && "
 570                 "     %(clone_ns3_cmd)s "
 571                 "  ) "
 572                 " ) "
 573                 ") "
 574                 " && "
 575                 "( "
 576                 "   %(clone_dce_cmd)s "
 577                 ") "
 578              ) % {
 579                     "ns3_src": self.ns3_src_location,
 580                     "pybindgen_version": self.get("pybindgenVersion"),
 581                     "pygccxml_version": self.pygccxml_version,
 582                     "clone_ns3_cmd": clone_ns3_cmd,
 583                     "clone_dce_cmd": clone_dce_cmd,
 584                  }
 585
 586         return ns3_build_cmd
 587
 588     @property
 589     def _install_dce_command(self):
 590         install_dce_cmd = " echo 'DCE will not be installed'"
 591
 592         if self.enable_dce:
 593             install_dce_cmd = (
 594                         " ( "
 595                         "   ((test -d %(ns3_build)s/bin_dce ) && "
 596                         "    echo 'dce binaries found, nothing to do' )"
 597                         " ) "
 598                         " ||"
 599                         " (   "
 600                          # If not, copy build to dce
 601                         "  cd %(dce_src)s && "
 602                         "  rm -rf %(dce_src)s/build && "
 603                         "  ./waf configure %(enable_opt)s --with-pybindgen=${SRC}/pybindgen/%(pybindgen_version)s "
 604                         "  --prefix=%(ns3_build)s --with-ns3=%(ns3_build)s && "
 605                         "  ./waf build && "
 606                         "  ./waf install && "
 607                         "  [ ! -e %(ns3_build)s/lib/python/site-packages/ns/dce.so ] && "
 608                         "   mv %(ns3_build)s/lib*/python*/site-packages/ns/dce.so %(ns3_build)s/lib/python/site-packages/ns/ "
 609                         " )"
 610                 ) % {
 611                     "pybindgen_version": self.get("pybindgenVersion"),
 612                     "enable_opt": "--enable-opt" if  self.get("buildMode") == "optimized" else "",
 613                     "ns3_build": self.ns3_build_location,
 614                     "dce_src": self.dce_src_location,
 615                      }
 616
 617         return install_dce_cmd
 618
 619     @property
 620     def _install(self):
 621         install_dce_cmd = self._install_dce_command
 622
 623         install_ns3_cmd = (
 624                  # Test if ns-3 is alredy installed
 625                 "("
 626                 " ( "
 627                 "  ( ( (test -d %(ns3_build)s/lib ) || "
 628                 "    (test -d ${NS3BINDINGS:='None'} && test -d ${NS3LIBRARIES:='None'}) ) && "
 629                 "    echo 'binaries found, nothing to do' )"
 630                 " ) "
 631                 " ||"
 632                 " (   "
 633                  # If not, copy ns-3 build to bin
 634                 "  mkdir -p %(ns3_build)s && "
 635                 "  cd %(ns3_src)s && "
 636                 "  rm -rf %(ns3_src)s/build && "
 637                 "  ./waf configure -d %(build_mode)s --with-pybindgen=${SRC}/pybindgen/%(pybindgen_version)s "
 638                 "  --prefix=%(ns3_build)s && "
 639                 "  ./waf build && "
 640                 "  ./waf install && "
 641                 "  mv %(ns3_build)s/lib*/python* %(ns3_build)s/lib/python "
 642                 " )"
 643                 ") "
 644                 " && "
 645                 "( "
 646                 "   %(install_dce_cmd)s "
 647                 ") "
 648               ) % {
 649                     "pybindgen_version": self.get("pybindgenVersion"),
 650                     "build_mode": self.get("buildMode"),
 651                     "install_dce_cmd": install_dce_cmd,
 652                     "ns3_build": self.ns3_build_location,
 653                     "ns3_src": self.ns3_src_location,
 654                  }
 655
 656         return install_ns3_cmd
 657
 658     @property
 659     def _environment(self):
 660         env = []
 661         env.append("PYTHONPATH=$PYTHONPATH:${NS3BINDINGS:=%(ns3_build)s/lib/python/site-packages}" % {
 662                     "ns3_build": self.ns3_build_location
 663                  })
 664         # If NS3LIBRARIES is defined and not empty, assign its value,
 665         # if not assign ns3_build_home/lib/ to NS3LIBRARIES and LD_LIBARY_PATH
 666         env.append("LD_LIBRARY_PATH=${NS3LIBRARIES:=%(ns3_build)s/lib}" % {
 667                     "ns3_build": self.ns3_build_location
 668                  })
 669         env.append("DCE_PATH=$NS3LIBRARIES/../bin_dce")
 670         env.append("DCE_ROOT=$NS3LIBRARIES/..")
 671
 672         return " ".join(env)
 673
 674     def replace_paths(self, command):
 675         """
 676         Replace all special path tags with shell-escaped actual paths.
 677         """
 678         return ( command
 679             .replace("${USR}", self.node.usr_dir)
 680             .replace("${LIB}", self.node.lib_dir)
 681             .replace("${BIN}", self.node.bin_dir)
 682             .replace("${SRC}", self.node.src_dir)
 683             .replace("${SHARE}", self.node.share_dir)
 684             .replace("${EXP}", self.node.exp_dir)
 685             .replace("${EXP_HOME}", self.node.exp_home)
 686             .replace("${APP_HOME}", self.app_home)
 687             .replace("${RUN_HOME}", self.run_home)
 688             .replace("${NODE_HOME}", self.node.node_home)
 689             .replace("${HOME}", self.node.home_dir)
 690             # If NS3LIBRARIES is defined and not empty, use that value,
 691             # if not use ns3_build_home/lib/
 692             .replace("${BIN_DCE}", "${NS3LIBRARIES-%s/lib}/../bin_dce" % \
 693                     self.ns3_build_location)
 694             )
 695
 696     def valid_connection(self, guid):
 697         # TODO: Validate!
 698         return True
 699
 700     def wait_remote_socket(self):
 701         """ Waits until the remote socket is created
 702         """
 703         command = " [ -e %s ] && echo 'DONE' " % self.remote_socket
 704
 705         for i in xrange(200):
 706             (out, err), proc = self.node.execute(command, retry = 1,
 707                     with_lock = True)
 708
 709             if out.find("DONE") > -1:
 710                 break
 711         else:
 712             raise RuntimeError("Remote socket not found at %s" % \
 713                     self.remote_socket)
 714
 715