Source code for openquake.server.dbserver

# -*- 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
# 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 <>.

import os
import sys
import time
import sqlite3
import logging
import threading
import subprocess

from openquake.baselib import config, 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,
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 = os.getpid() if ZMQ: self.zmaster = w.WorkerMaster(address[0], **config.zworkers) else: self.zmaster = None
[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( continue elif cmd.startswith('zmq_') and self.zmaster: msg = getattr(self.zmaster, cmd[4:])() sock.send(msg) 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, if ZMQ: # start task_in->task_server streamer thread c = config.zworkers threading.Thread( target=w._streamer, args=(self.master_host,), daemon=True ).start() logging.warning('Task streamer started on port %d', int(c.ctrl_port) + 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.ContextTerminated): 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: self.zmaster.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.listen, 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 hangs after the end of the first # calculation, but only if the DbServer is started by oq engine (!?) subprocess.Popen([sys.executable, '-m', 'openquake.commands', 'dbserver', 'start']) # 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]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. """ # configure the logging first of all logging.basicConfig(level=getattr(logging, loglevel.upper())) 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 db.close() # reset any computation left in the 'executing' state actions.reset_is_running(db) # start the dbserver if hasattr(os, 'fork') and not (config.dbserver.multi_user or foreground): # needed for # 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