osm_lcm/lcm.py

   1 #!/usr/bin/python3
   2 # -*- coding: utf-8 -*-
   3
   4 ##
   5 # Copyright 2018 Telefonica S.A.
   6 #
   7 # Licensed under the Apache License, Version 2.0 (the "License"); you may
   8 # not use this file except in compliance with the License. You may obtain
   9 # a copy of the License at
  10 #
  11 #         http://www.apache.org/licenses/LICENSE-2.0
  12 #
  13 # Unless required by applicable law or agreed to in writing, software
  14 # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  15 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  16 # License for the specific language governing permissions and limitations
  17 # under the License.
  18 ##
  19
  20 import asyncio
  21 import yaml
  22 import logging
  23 import logging.handlers
  24 import getopt
  25 import sys
  26 import ROclient
  27 import ns
  28 import vim_sdn
  29 import netslice
  30 from lcm_utils import versiontuple, LcmException, TaskRegistry, LcmExceptionExit
  31
  32 # from osm_lcm import version as lcm_version, version_date as lcm_version_date, ROclient
  33 from osm_common import dbmemory, dbmongo, fslocal, msglocal, msgkafka
  34 from osm_common import version as common_version
  35 from osm_common.dbbase import DbException
  36 from osm_common.fsbase import FsException
  37 from osm_common.msgbase import MsgException
  38 from os import environ, path
  39 from n2vc import version as n2vc_version
  40
  41
  42 __author__ = "Alfonso Tierno"
  43 min_RO_version = [0, 6, 3]
  44 min_n2vc_version = "0.0.2"
  45 min_common_version = "0.1.11"
  46 # uncomment if LCM is installed as library and installed, and get them from __init__.py
  47 lcm_version = '0.1.32'
  48 lcm_version_date = '2019-01-28'
  49
  50
  51 class Lcm:
  52
  53     ping_interval_pace = 120  # how many time ping is send once is confirmed all is running
  54     ping_interval_boot = 5    # how many time ping is sent when booting
  55
  56     def __init__(self, config_file, loop=None):
  57         """
  58         Init, Connect to database, filesystem storage, and messaging
  59         :param config: two level dictionary with configuration. Top level should contain 'database', 'storage',
  60         :return: None
  61         """
  62
  63         self.db = None
  64         self.msg = None
  65         self.fs = None
  66         self.pings_not_received = 1
  67         self.consecutive_errors = 0
  68         self.first_start = False
  69
  70         # contains created tasks/futures to be able to cancel
  71         self.lcm_tasks = TaskRegistry()
  72         # logging
  73         self.logger = logging.getLogger('lcm')
  74         # load configuration
  75         config = self.read_config_file(config_file)
  76         self.config = config
  77         self.ro_config = {
  78             "endpoint_url": "http://{}:{}/openmano".format(config["RO"]["host"], config["RO"]["port"]),
  79             "tenant": config.get("tenant", "osm"),
  80             "logger_name": "lcm.ROclient",
  81             "loglevel": "ERROR",
  82         }
  83
  84         self.vca_config = config["VCA"]
  85
  86         self.loop = loop or asyncio.get_event_loop()
  87
  88         # logging
  89         log_format_simple = "%(asctime)s %(levelname)s %(name)s %(filename)s:%(lineno)s %(message)s"
  90         log_formatter_simple = logging.Formatter(log_format_simple, datefmt='%Y-%m-%dT%H:%M:%S')
  91         config["database"]["logger_name"] = "lcm.db"
  92         config["storage"]["logger_name"] = "lcm.fs"
  93         config["message"]["logger_name"] = "lcm.msg"
  94         if config["global"].get("logfile"):
  95             file_handler = logging.handlers.RotatingFileHandler(config["global"]["logfile"],
  96                                                                 maxBytes=100e6, backupCount=9, delay=0)
  97             file_handler.setFormatter(log_formatter_simple)
  98             self.logger.addHandler(file_handler)
  99         if not config["global"].get("nologging"):
 100             str_handler = logging.StreamHandler()
 101             str_handler.setFormatter(log_formatter_simple)
 102             self.logger.addHandler(str_handler)
 103
 104         if config["global"].get("loglevel"):
 105             self.logger.setLevel(config["global"]["loglevel"])
 106
 107         # logging other modules
 108         for k1, logname in {"message": "lcm.msg", "database": "lcm.db", "storage": "lcm.fs"}.items():
 109             config[k1]["logger_name"] = logname
 110             logger_module = logging.getLogger(logname)
 111             if config[k1].get("logfile"):
 112                 file_handler = logging.handlers.RotatingFileHandler(config[k1]["logfile"],
 113                                                                     maxBytes=100e6, backupCount=9, delay=0)
 114                 file_handler.setFormatter(log_formatter_simple)
 115                 logger_module.addHandler(file_handler)
 116             if config[k1].get("loglevel"):
 117                 logger_module.setLevel(config[k1]["loglevel"])
 118         self.logger.critical("starting osm/lcm version {} {}".format(lcm_version, lcm_version_date))
 119
 120         # check version of N2VC
 121         # TODO enhance with int conversion or from distutils.version import LooseVersion
 122         # or with list(map(int, version.split(".")))
 123         if versiontuple(n2vc_version) < versiontuple(min_n2vc_version):
 124             raise LcmException("Not compatible osm/N2VC version '{}'. Needed '{}' or higher".format(
 125                 n2vc_version, min_n2vc_version))
 126         # check version of common
 127         if versiontuple(common_version) < versiontuple(min_common_version):
 128             raise LcmException("Not compatible osm/common version '{}'. Needed '{}' or higher".format(
 129                 common_version, min_common_version))
 130
 131         try:
 132             # TODO check database version
 133             if config["database"]["driver"] == "mongo":
 134                 self.db = dbmongo.DbMongo()
 135                 self.db.db_connect(config["database"])
 136             elif config["database"]["driver"] == "memory":
 137                 self.db = dbmemory.DbMemory()
 138                 self.db.db_connect(config["database"])
 139             else:
 140                 raise LcmException("Invalid configuration param '{}' at '[database]':'driver'".format(
 141                     config["database"]["driver"]))
 142
 143             if config["storage"]["driver"] == "local":
 144                 self.fs = fslocal.FsLocal()
 145                 self.fs.fs_connect(config["storage"])
 146             else:
 147                 raise LcmException("Invalid configuration param '{}' at '[storage]':'driver'".format(
 148                     config["storage"]["driver"]))
 149
 150             config_message = config["message"].copy()
 151             config_message["loop"] = self.loop
 152             if config_message["driver"] == "local":
 153                 self.msg = msglocal.MsgLocal()
 154                 self.msg.connect(config_message)
 155             elif config_message["driver"] == "kafka":
 156                 self.msg = msgkafka.MsgKafka()
 157                 self.msg.connect(config_message)
 158             else:
 159                 raise LcmException("Invalid configuration param '{}' at '[message]':'driver'".format(
 160                     config["message"]["driver"]))
 161         except (DbException, FsException, MsgException) as e:
 162             self.logger.critical(str(e), exc_info=True)
 163             raise LcmException(str(e))
 164
 165         self.ns = ns.NsLcm(self.db, self.msg, self.fs, self.lcm_tasks, self.ro_config, self.vca_config, self.loop)
 166         self.netslice = netslice.NetsliceLcm(self.db, self.msg, self.fs, self.lcm_tasks, self.ro_config,
 167                                              self.vca_config, self.loop)
 168         self.vim = vim_sdn.VimLcm(self.db, self.msg, self.fs, self.lcm_tasks, self.ro_config, self.loop)
 169         self.wim = vim_sdn.WimLcm(self.db, self.msg, self.fs, self.lcm_tasks, self.ro_config, self.loop)
 170         self.sdn = vim_sdn.SdnLcm(self.db, self.msg, self.fs, self.lcm_tasks, self.ro_config, self.loop)
 171
 172     async def check_RO_version(self):
 173         try:
 174             RO = ROclient.ROClient(self.loop, **self.ro_config)
 175             RO_version = await RO.get_version()
 176             if RO_version < min_RO_version:
 177                 raise LcmException("Not compatible osm/RO version '{}.{}.{}'. Needed '{}.{}.{}' or higher".format(
 178                     *RO_version, *min_RO_version
 179                 ))
 180         except ROclient.ROClientException as e:
 181             error_text = "Error while conneting to osm/RO " + str(e)
 182             self.logger.critical(error_text, exc_info=True)
 183             raise LcmException(error_text)
 184
 185     async def test(self, param=None):
 186         self.logger.debug("Starting/Ending test task: {}".format(param))
 187
 188     async def kafka_ping(self):
 189         self.logger.debug("Task kafka_ping Enter")
 190         consecutive_errors = 0
 191         first_start = True
 192         kafka_has_received = False
 193         self.pings_not_received = 1
 194         while True:
 195             try:
 196                 await self.msg.aiowrite("admin", "ping", {"from": "lcm", "to": "lcm"}, self.loop)
 197                 # time between pings are low when it is not received and at starting
 198                 wait_time = self.ping_interval_boot if not kafka_has_received else self.ping_interval_pace
 199                 if not self.pings_not_received:
 200                     kafka_has_received = True
 201                 self.pings_not_received += 1
 202                 await asyncio.sleep(wait_time, loop=self.loop)
 203                 if self.pings_not_received > 10:
 204                     raise LcmException("It is not receiving pings from Kafka bus")
 205                 consecutive_errors = 0
 206                 first_start = False
 207             except LcmException:
 208                 raise
 209             except Exception as e:
 210                 # if not first_start is the first time after starting. So leave more time and wait
 211                 # to allow kafka starts
 212                 if consecutive_errors == 8 if not first_start else 30:
 213                     self.logger.error("Task kafka_read task exit error too many errors. Exception: {}".format(e))
 214                     raise
 215                 consecutive_errors += 1
 216                 self.logger.error("Task kafka_read retrying after Exception {}".format(e))
 217                 wait_time = 1 if not first_start else 5
 218                 await asyncio.sleep(wait_time, loop=self.loop)
 219
 220     def kafka_read_callback(self, topic, command, params):
 221         order_id = 1
 222
 223         if topic != "admin" and command != "ping":
 224             self.logger.debug("Task kafka_read receives {} {}: {}".format(topic, command, params))
 225         self.consecutive_errors = 0
 226         self.first_start = False
 227         order_id += 1
 228         if command == "exit":
 229             raise LcmExceptionExit
 230         elif command.startswith("#"):
 231             return
 232         elif command == "echo":
 233             # just for test
 234             print(params)
 235             sys.stdout.flush()
 236             return
 237         elif command == "test":
 238             asyncio.Task(self.test(params), loop=self.loop)
 239             return
 240
 241         if topic == "admin":
 242             if command == "ping" and params["to"] == "lcm" and params["from"] == "lcm":
 243                 self.pings_not_received = 0
 244             return
 245         elif topic == "ns":
 246             if command == "instantiate":
 247                 # self.logger.debug("Deploying NS {}".format(nsr_id))
 248                 nslcmop = params
 249                 nslcmop_id = nslcmop["_id"]
 250                 nsr_id = nslcmop["nsInstanceId"]
 251                 task = asyncio.ensure_future(self.ns.instantiate(nsr_id, nslcmop_id))
 252                 self.lcm_tasks.register("ns", nsr_id, nslcmop_id, "ns_instantiate", task)
 253                 return
 254             elif command == "terminate":
 255                 # self.logger.debug("Deleting NS {}".format(nsr_id))
 256                 nslcmop = params
 257                 nslcmop_id = nslcmop["_id"]
 258                 nsr_id = nslcmop["nsInstanceId"]
 259                 self.lcm_tasks.cancel(topic, nsr_id)
 260                 task = asyncio.ensure_future(self.ns.terminate(nsr_id, nslcmop_id))
 261                 self.lcm_tasks.register("ns", nsr_id, nslcmop_id, "ns_terminate", task)
 262                 return
 263             elif command == "action":
 264                 # self.logger.debug("Update NS {}".format(nsr_id))
 265                 nslcmop = params
 266                 nslcmop_id = nslcmop["_id"]
 267                 nsr_id = nslcmop["nsInstanceId"]
 268                 task = asyncio.ensure_future(self.ns.action(nsr_id, nslcmop_id))
 269                 self.lcm_tasks.register("ns", nsr_id, nslcmop_id, "ns_action", task)
 270                 return
 271             elif command == "scale":
 272                 # self.logger.debug("Update NS {}".format(nsr_id))
 273                 nslcmop = params
 274                 nslcmop_id = nslcmop["_id"]
 275                 nsr_id = nslcmop["nsInstanceId"]
 276                 task = asyncio.ensure_future(self.ns.scale(nsr_id, nslcmop_id))
 277                 self.lcm_tasks.register("ns", nsr_id, nslcmop_id, "ns_scale", task)
 278                 return
 279             elif command == "show":
 280                 nsr_id = params
 281                 try:
 282                     db_nsr = self.db.get_one("nsrs", {"_id": nsr_id})
 283                     print("nsr:\n    _id={}\n    operational-status: {}\n    config-status: {}"
 284                           "\n    detailed-status: {}\n    deploy: {}\n    tasks: {}"
 285                           "".format(nsr_id, db_nsr["operational-status"], db_nsr["config-status"],
 286                                     db_nsr["detailed-status"],
 287                                     db_nsr["_admin"]["deployed"], self.lcm_ns_tasks.get(nsr_id)))
 288                 except Exception as e:
 289                     print("nsr {} not found: {}".format(nsr_id, e))
 290                 sys.stdout.flush()
 291                 return
 292             elif command == "deleted":
 293                 return  # TODO cleaning of task just in case should be done
 294             elif command in ("terminated", "instantiated", "scaled", "actioned"):  # "scaled-cooldown-time"
 295                 return
 296         elif topic == "nsi":  # netslice LCM processes (instantiate, terminate, etc)
 297             if command == "instantiate":
 298                 # self.logger.debug("Instantiating Network Slice {}".format(nsilcmop["netsliceInstanceId"]))
 299                 nsilcmop = params
 300                 nsilcmop_id = nsilcmop["_id"]  # slice operation id
 301                 nsir_id = nsilcmop["netsliceInstanceId"]  # slice record id
 302                 task = asyncio.ensure_future(self.netslice.instantiate(nsir_id, nsilcmop_id))
 303                 self.lcm_tasks.register("nsi", nsir_id, nsilcmop_id, "nsi_instantiate", task)
 304                 return
 305             elif command == "terminate":
 306                 # self.logger.debug("Terminating Network Slice NS {}".format(nsilcmop["netsliceInstanceId"]))
 307                 nsilcmop = params
 308                 nsilcmop_id = nsilcmop["_id"]  # slice operation id
 309                 nsir_id = nsilcmop["netsliceInstanceId"]  # slice record id
 310                 self.lcm_tasks.cancel(topic, nsir_id)
 311                 task = asyncio.ensure_future(self.netslice.terminate(nsir_id, nsilcmop_id))
 312                 self.lcm_tasks.register("nsi", nsir_id, nsilcmop_id, "nsi_terminate", task)
 313                 return
 314             elif command == "show":
 315                 nsir_id = params
 316                 try:
 317                     db_nsir = self.db.get_one("nsirs", {"_id": nsir_id})
 318                     print("nsir:\n    _id={}\n    operational-status: {}\n    config-status: {}"
 319                           "\n    detailed-status: {}\n    deploy: {}\n    tasks: {}"
 320                           "".format(nsir_id, db_nsir["operational-status"], db_nsir["config-status"],
 321                                     db_nsir["detailed-status"],
 322                                     db_nsir["_admin"]["deployed"], self.lcm_netslice_tasks.get(nsir_id)))
 323                 except Exception as e:
 324                     print("nsir {} not found: {}".format(nsir_id, e))
 325                 sys.stdout.flush()
 326                 return
 327             elif command == "deleted":
 328                 return  # TODO cleaning of task just in case should be done
 329             elif command in ("terminated", "instantiated", "scaled", "actioned"):  # "scaled-cooldown-time"
 330                 return
 331         elif topic == "vim_account":
 332             vim_id = params["_id"]
 333             if command == "create":
 334                 task = asyncio.ensure_future(self.vim.create(params, order_id))
 335                 self.lcm_tasks.register("vim_account", vim_id, order_id, "vim_create", task)
 336                 return
 337             elif command == "delete":
 338                 self.lcm_tasks.cancel(topic, vim_id)
 339                 task = asyncio.ensure_future(self.vim.delete(vim_id, order_id))
 340                 self.lcm_tasks.register("vim_account", vim_id, order_id, "vim_delete", task)
 341                 return
 342             elif command == "show":
 343                 print("not implemented show with vim_account")
 344                 sys.stdout.flush()
 345                 return
 346             elif command == "edit":
 347                 task = asyncio.ensure_future(self.vim.edit(params, order_id))
 348                 self.lcm_tasks.register("vim_account", vim_id, order_id, "vim_edit", task)
 349                 return
 350         elif topic == "wim_account":
 351             wim_id = params["_id"]
 352             if command == "create":
 353                 task = asyncio.ensure_future(self.wim.create(params, order_id))
 354                 self.lcm_tasks.register("wim_account", wim_id, order_id, "wim_create", task)
 355                 return
 356             elif command == "delete":
 357                 self.lcm_tasks.cancel(topic, wim_id)
 358                 task = asyncio.ensure_future(self.wim.delete(wim_id, order_id))
 359                 self.lcm_tasks.register("wim_account", wim_id, order_id, "wim_delete", task)
 360                 return
 361             elif command == "show":
 362                 print("not implemented show with wim_account")
 363                 sys.stdout.flush()
 364                 return
 365             elif command == "edit":
 366                 task = asyncio.ensure_future(self.wim.edit(params, order_id))
 367                 self.lcm_tasks.register("wim_account", wim_id, order_id, "wim_edit", task)
 368                 return
 369         elif topic == "sdn":
 370             _sdn_id = params["_id"]
 371             if command == "create":
 372                 task = asyncio.ensure_future(self.sdn.create(params, order_id))
 373                 self.lcm_tasks.register("sdn", _sdn_id, order_id, "sdn_create", task)
 374                 return
 375             elif command == "delete":
 376                 self.lcm_tasks.cancel(topic, _sdn_id)
 377                 task = asyncio.ensure_future(self.sdn.delete(_sdn_id, order_id))
 378                 self.lcm_tasks.register("sdn", _sdn_id, order_id, "sdn_delete", task)
 379                 return
 380             elif command == "edit":
 381                 task = asyncio.ensure_future(self.sdn.edit(params, order_id))
 382                 self.lcm_tasks.register("sdn", _sdn_id, order_id, "sdn_edit", task)
 383                 return
 384         self.logger.critical("unknown topic {} and command '{}'".format(topic, command))
 385
 386     async def kafka_read(self):
 387         self.logger.debug("Task kafka_read Enter")
 388         # future = asyncio.Future()
 389         self.consecutive_errors = 0
 390         self.first_start = True
 391         while self.consecutive_errors < 10:
 392             try:
 393                 topics = ("admin", "ns", "vim_account", "wim_account", "sdn", "nsi")
 394                 await self.msg.aioread(topics, self.loop, self.kafka_read_callback)
 395
 396             except LcmExceptionExit:
 397                 self.logger.debug("Bye!")
 398                 break
 399             except Exception as e:
 400                 # if not first_start is the first time after starting. So leave more time and wait
 401                 # to allow kafka starts
 402                 if self.consecutive_errors == 8 if not self.first_start else 30:
 403                     self.logger.error("Task kafka_read task exit error too many errors. Exception: {}".format(e))
 404                     raise
 405                 self.consecutive_errors += 1
 406                 self.logger.error("Task kafka_read retrying after Exception {}".format(e))
 407                 wait_time = 2 if not self.first_start else 5
 408                 await asyncio.sleep(wait_time, loop=self.loop)
 409
 410         # self.logger.debug("Task kafka_read terminating")
 411         self.logger.debug("Task kafka_read exit")
 412
 413     def health_check(self):
 414
 415         global exit_code
 416         task = None
 417         exit_code = 1
 418
 419         def health_check_callback(topic, command, params):
 420             global exit_code
 421             print("receiving callback {} {} {}".format(topic, command, params))
 422             if topic == "admin" and command == "ping" and params["to"] == "lcm" and params["from"] == "lcm":
 423                 # print("received LCM ping")
 424                 exit_code = 0
 425                 task.cancel()
 426
 427         try:
 428             task = asyncio.ensure_future(self.msg.aioread(("admin",), self.loop, health_check_callback))
 429             self.loop.run_until_complete(task)
 430         except Exception:
 431             pass
 432         exit(exit_code)
 433
 434     def start(self):
 435
 436         # check RO version
 437         self.loop.run_until_complete(self.check_RO_version())
 438
 439         self.loop.run_until_complete(asyncio.gather(
 440             self.kafka_read(),
 441             self.kafka_ping()
 442         ))
 443         # TODO
 444         # self.logger.debug("Terminating cancelling creation tasks")
 445         # self.lcm_tasks.cancel("ALL", "create")
 446         # timeout = 200
 447         # while self.is_pending_tasks():
 448         #     self.logger.debug("Task kafka_read terminating. Waiting for tasks termination")
 449         #     await asyncio.sleep(2, loop=self.loop)
 450         #     timeout -= 2
 451         #     if not timeout:
 452         #         self.lcm_tasks.cancel("ALL", "ALL")
 453         self.loop.close()
 454         self.loop = None
 455         if self.db:
 456             self.db.db_disconnect()
 457         if self.msg:
 458             self.msg.disconnect()
 459         if self.fs:
 460             self.fs.fs_disconnect()
 461
 462     def read_config_file(self, config_file):
 463         # TODO make a [ini] + yaml inside parser
 464         # the configparser library is not suitable, because it does not admit comments at the end of line,
 465         # and not parse integer or boolean
 466         try:
 467             with open(config_file) as f:
 468                 conf = yaml.load(f)
 469             for k, v in environ.items():
 470                 if not k.startswith("OSMLCM_"):
 471                     continue
 472                 k_items = k.lower().split("_")
 473                 if len(k_items) < 3:
 474                     continue
 475                 if k_items[1] in ("ro", "vca"):
 476                     # put in capital letter
 477                     k_items[1] = k_items[1].upper()
 478                 c = conf
 479                 try:
 480                     for k_item in k_items[1:-1]:
 481                         c = c[k_item]
 482                     if k_items[-1] == "port":
 483                         c[k_items[-1]] = int(v)
 484                     else:
 485                         c[k_items[-1]] = v
 486                 except Exception as e:
 487                     self.logger.warn("skipping environ '{}' on exception '{}'".format(k, e))
 488
 489             return conf
 490         except Exception as e:
 491             self.logger.critical("At config file '{}': {}".format(config_file, e))
 492             exit(1)
 493
 494
 495 def usage():
 496     print("""Usage: {} [options]
 497         -c|--config [configuration_file]: loads the configuration file (default: ./nbi.cfg)
 498         --health-check: do not run lcm, but inspect kafka bus to determine if lcm is healthy
 499         -h|--help: shows this help
 500         """.format(sys.argv[0]))
 501     # --log-socket-host HOST: send logs to this host")
 502     # --log-socket-port PORT: send logs using this port (default: 9022)")
 503
 504
 505 if __name__ == '__main__':
 506     try:
 507         # load parameters and configuration
 508         opts, args = getopt.getopt(sys.argv[1:], "hc:", ["config=", "help", "health-check"])
 509         # TODO add  "log-socket-host=", "log-socket-port=", "log-file="
 510         config_file = None
 511         health_check = None
 512         for o, a in opts:
 513             if o in ("-h", "--help"):
 514                 usage()
 515                 sys.exit()
 516             elif o in ("-c", "--config"):
 517                 config_file = a
 518             elif o == "--health-check":
 519                 health_check = True
 520             # elif o == "--log-socket-port":
 521             #     log_socket_port = a
 522             # elif o == "--log-socket-host":
 523             #     log_socket_host = a
 524             # elif o == "--log-file":
 525             #     log_file = a
 526             else:
 527                 assert False, "Unhandled option"
 528         if config_file:
 529             if not path.isfile(config_file):
 530                 print("configuration file '{}' not exist".format(config_file), file=sys.stderr)
 531                 exit(1)
 532         else:
 533             for config_file in (__file__[:__file__.rfind(".")] + ".cfg", "./lcm.cfg", "/etc/osm/lcm.cfg"):
 534                 if path.isfile(config_file):
 535                     break
 536             else:
 537                 print("No configuration file 'lcm.cfg' found neither at local folder nor at /etc/osm/", file=sys.stderr)
 538                 exit(1)
 539         lcm = Lcm(config_file)
 540         if health_check:
 541             lcm.health_check()
 542         else:
 543             lcm.start()
 544     except (LcmException, getopt.GetoptError) as e:
 545         print(str(e), file=sys.stderr)
 546         # usage()
 547         exit(1)