# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright (C) 2016-2019 GEM Foundation
#
# OpenQuake is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# OpenQuake is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with OpenQuake. If not, see <http://www.gnu.org/licenses/>.
import os
import sys
import time
import sqlite3
import logging
import threading
import subprocess
from openquake.baselib import config, sap, zeromq as z, workerpool as w
from openquake.baselib.general import socket_ready, detach_process
from openquake.baselib.parallel import safely_call
from openquake.commonlib import logs
from openquake.server.db import actions
from openquake.server import dbapi
from openquake.server import __file__ as server_path
db = dbapi.Db(sqlite3.connect, os.path.expanduser(config.dbserver.file),
isolation_level=None, detect_types=sqlite3.PARSE_DECLTYPES,
timeout=20)
db.cmd = lambda action, *args: getattr(actions, action)(db, *args)
# NB: I am increasing the timeout from 5 to 20 seconds to see if the random
# OperationalError: "database is locked" disappear in the WebUI tests
ZMQ = os.environ.get(
'OQ_DISTRIBUTE', config.distribution.oq_distribute) == 'zmq'
DBSERVER_PORT = int(os.environ.get('OQ_DBSERVER_PORT') or config.dbserver.port)
[docs]class DbServer(object):
"""
A server collecting the received commands into a queue
"""
def __init__(self, db, address, num_workers=5):
self.db = db
self.master_host = address[0]
self.frontend = 'tcp://%s:%s' % address
self.backend = 'inproc://dbworkers'
self.num_workers = num_workers
self.pid = os.getpid()
self.master = w.WorkerMaster(config.dbserver.host,
**config.zworkers)
[docs] def dworker(self, sock):
# a database worker responding to commands
with sock:
for cmd_ in sock:
cmd, args = cmd_[0], cmd_[1:]
if cmd == 'getpid':
sock.send(self.pid)
continue
try:
func = getattr(actions, cmd)
except AttributeError: # SQL string
sock.send(safely_call(self.db, (cmd,) + args))
else: # action
sock.send(safely_call(func, (self.db,) + args))
[docs] def start(self):
"""
Start database worker threads
"""
# give a nice name to the process
w.setproctitle('oq-dbserver')
dworkers = []
for _ in range(self.num_workers):
sock = z.Socket(self.backend, z.zmq.REP, 'connect')
threading.Thread(target=self.dworker, args=(sock,)).start()
dworkers.append(sock)
logging.warning('DB server started with %s on %s, pid %d',
sys.executable, self.frontend, self.pid)
if ZMQ:
# start task_in->task_out streamer thread
c = config.zworkers
threading.Thread(
target=w._streamer,
args=(self.master_host, c.task_in_port, c.task_out_port)
).start()
logging.warning('Task streamer started from %s -> %s',
c.task_in_port, c.task_out_port)
# start zworkers and wait a bit for them
msg = self.master.start()
logging.warning(msg)
time.sleep(1)
# start frontend->backend proxy for the database workers
try:
z.zmq.proxy(z.bind(self.frontend, z.zmq.ROUTER),
z.bind(self.backend, z.zmq.DEALER))
except (KeyboardInterrupt, z.zmq.ZMQError):
for sock in dworkers:
sock.running = False
sock.zsocket.close()
logging.warning('DB server stopped')
finally:
self.stop()
[docs] def stop(self):
"""Stop the DbServer and the zworkers if any"""
if ZMQ:
logging.warning(self.master.stop())
z.context.term()
self.db.close()
[docs]def different_paths(path1, path2):
path1 = os.path.realpath(path1) # expand symlinks
path2 = os.path.realpath(path2) # expand symlinks
# don't care about the extension (it may be .py or .pyc)
return os.path.splitext(path1)[0] != os.path.splitext(path2)[0]
[docs]def get_status(address=None):
"""
Check if the DbServer is up.
:param address: pair (hostname, port)
:returns: 'running' or 'not-running'
"""
address = address or (config.dbserver.host, DBSERVER_PORT)
return 'running' if socket_ready(address) else 'not-running'
[docs]def check_foreign():
"""
Check if we the DbServer is the right one
"""
if not config.dbserver.multi_user:
remote_server_path = logs.dbcmd('get_path')
if different_paths(server_path, remote_server_path):
return('You are trying to contact a DbServer from another'
' instance (got %s, expected %s)\n'
'Check the configuration or stop the foreign'
' DbServer instance') % (remote_server_path, server_path)
[docs]def ensure_on():
"""
Start the DbServer if it is off
"""
if get_status() == 'not-running':
if config.dbserver.multi_user:
sys.exit('Please start the DbServer: '
'see the documentation for details')
# otherwise start the DbServer automatically; NB: I tried to use
# multiprocessing.Process(target=run_server).start() and apparently
# it works, but then run-demos.sh hangs after the end of the first
# calculation, but only if the DbServer is started by oq engine (!?)
subprocess.Popen([sys.executable, '-m', 'openquake.server.dbserver',
'-l', 'INFO'])
# wait for the dbserver to start
waiting_seconds = 30
while get_status() == 'not-running':
if waiting_seconds == 0:
sys.exit('The DbServer cannot be started after 30 seconds. '
'Please check the configuration')
time.sleep(1)
waiting_seconds -= 1
[docs]@sap.script
def run_server(dbpath=os.path.expanduser(config.dbserver.file),
dbhostport=None, loglevel='WARN', foreground=False):
"""
Run the DbServer on the given database file and port. If not given,
use the settings in openquake.cfg.
"""
if dbhostport: # assume a string of the form "dbhost:port"
dbhost, port = dbhostport.split(':')
addr = (dbhost, int(port))
else:
addr = (config.dbserver.listen, DBSERVER_PORT)
# create the db directory if needed
dirname = os.path.dirname(dbpath)
if not os.path.exists(dirname):
os.makedirs(dirname)
# create and upgrade the db if needed
db('PRAGMA foreign_keys = ON') # honor ON DELETE CASCADE
actions.upgrade_db(db)
# the line below is needed to work around a very subtle bug of sqlite;
# we need new connections, see https://github.com/gem/oq-engine/pull/3002
db.close()
# reset any computation left in the 'executing' state
actions.reset_is_running(db)
# configure logging and start the server
logging.basicConfig(level=getattr(logging, loglevel))
if hasattr(os, 'fork') and not (config.dbserver.multi_user or foreground):
# needed for https://github.com/gem/oq-engine/issues/3211
# but only if multi_user = False, otherwise init/supervisor
# will loose control of the process
detach_process()
DbServer(db, addr).start() # expects to be killed with CTRL-C
run_server.arg('dbpath', 'dbpath')
run_server.arg('dbhostport', 'dbhost:port')
run_server.opt('loglevel', 'WARN or INFO')
if __name__ == '__main__':
run_server.callfunc()