Ejemplo n.º 1
0
    def _wait_child(self):
        try:
            # Don't block if no child processes have exited
            pid, status = os.waitpid(0, os.WNOHANG)
            if not pid:
                return None
        except OSError as exc:
            if exc.errno not in (errno.EINTR, errno.ECHILD):
                raise
            return None

        if os.WIFSIGNALED(status):
            sig = os.WTERMSIG(status)
            LOG.info(_LI("Child %(pid)d killed by signal %(sig)d"), dict(pid=pid, sig=sig))
        else:
            code = os.WEXITSTATUS(status)
            LOG.info(_LI("Child %(pid)s exited with status %(code)d"), dict(pid=pid, code=code))

        if pid not in self.children:
            LOG.warning(_LW("pid %d not in child list"), pid)
            return None

        wrap = self.children.pop(pid)
        wrap.children.remove(pid)
        return wrap
Ejemplo n.º 2
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    def wait(self):
        """Loop waiting on children to die and respawning as necessary."""

        systemd.notify_once()
        LOG.debug("Full set of CONF:")
        CONF.log_opt_values(LOG, std_logging.DEBUG)

        try:
            while True:
                self.handle_signal()
                self._respawn_children()
                # No signal means that stop was called.  Don't clean up here.
                if not self.sigcaught:
                    return

                signame = _signo_to_signame(self.sigcaught)
                LOG.info(_LI("Caught %s, stopping children"), signame)
                if not _is_sighup_and_daemon(self.sigcaught):
                    break

                for pid in self.children:
                    os.kill(pid, signal.SIGHUP)
                self.running = True
                self.sigcaught = None
        except eventlet.greenlet.GreenletExit:
            LOG.info(_LI("Wait called after thread killed.  Cleaning up."))

        self.stop()
Ejemplo n.º 3
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    def _start_child(self, wrap):
        if len(wrap.forktimes) > wrap.workers:
            # Limit ourselves to one process a second (over the period of
            # number of workers * 1 second). This will allow workers to
            # start up quickly but ensure we don't fork off children that
            # die instantly too quickly.
            if time.time() - wrap.forktimes[0] < wrap.workers:
                LOG.info(_LI("Forking too fast, sleeping"))
                time.sleep(1)

            wrap.forktimes.pop(0)

        wrap.forktimes.append(time.time())

        pid = os.fork()
        if pid == 0:
            launcher = self._child_process(wrap.service)
            while True:
                self._child_process_handle_signal()
                status, signo = self._child_wait_for_exit_or_signal(launcher)
                if not _is_sighup_and_daemon(signo):
                    break
                launcher.restart()

            os._exit(status)

        LOG.info(_LI("Started child %d"), pid)

        wrap.children.add(pid)
        self.children[pid] = wrap

        return pid
Ejemplo n.º 4
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    def _wait_for_exit_or_signal(self, ready_callback=None):
        status = None
        signo = 0

        LOG.debug("Full set of CONF:")
        CONF.log_opt_values(LOG, std_logging.DEBUG)

        try:
            if ready_callback:
                ready_callback()
            super(ServiceLauncher, self).wait()
        except SignalExit as exc:
            signame = _signo_to_signame(exc.signo)
            LOG.info(_LI("Caught %s, exiting"), signame)
            status = exc.code
            signo = exc.signo
        except SystemExit as exc:
            status = exc.code
        finally:
            self.stop()
            if rpc:
                try:
                    rpc.cleanup()
                except Exception:
                    # We're shutting down, so it doesn't matter at this point.
                    LOG.exception(_LE("Exception during rpc cleanup."))

        return status, signo
Ejemplo n.º 5
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    def _pipe_watcher(self):
        # This will block until the write end is closed when the parent
        # dies unexpectedly
        self.readpipe.read()

        LOG.info(_LI("Parent process has died unexpectedly, exiting"))

        sys.exit(1)
Ejemplo n.º 6
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    def __init__(cls, names, bases, dict_):
        """Metaclass that allows us to collect decorated periodic tasks."""
        super(_PeriodicTasksMeta, cls).__init__(names, bases, dict_)

        # NOTE(sirp): if the attribute is not present then we must be the base
        # class, so, go ahead an initialize it. If the attribute is present,
        # then we're a subclass so make a copy of it so we don't step on our
        # parent's toes.
        try:
            cls._periodic_tasks = cls._periodic_tasks[:]
        except AttributeError:
            cls._periodic_tasks = []

        try:
            cls._periodic_spacing = cls._periodic_spacing.copy()
        except AttributeError:
            cls._periodic_spacing = {}

        for value in cls.__dict__.values():
            if getattr(value, '_periodic_task', False):
                task = value
                name = task.__name__

                if task._periodic_spacing < 0:
                    LOG.info(_LI('Skipping periodic task %(task)s because '
                                 'its interval is negative'),
                             {'task': name})
                    continue
                if not task._periodic_enabled:
                    LOG.info(_LI('Skipping periodic task %(task)s because '
                                 'it is disabled'),
                             {'task': name})
                    continue

                # A periodic spacing of zero indicates that this task should
                # be run on the default interval to avoid running too
                # frequently.
                if task._periodic_spacing == 0:
                    task._periodic_spacing = DEFAULT_INTERVAL

                cls._periodic_tasks.append((name, task))
                cls._periodic_spacing[name] = task._periodic_spacing
Ejemplo n.º 7
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def drop_old_duplicate_entries_from_table(migrate_engine, table_name,
                                          use_soft_delete, *uc_column_names):
    """Drop all old rows having the same values for columns in uc_columns.

    This method drop (or mark ad `deleted` if use_soft_delete is True) old
    duplicate rows form table with name `table_name`.

    :param migrate_engine:  Sqlalchemy engine
    :param table_name:      Table with duplicates
    :param use_soft_delete: If True - values will be marked as `deleted`,
                            if False - values will be removed from table
    :param uc_column_names: Unique constraint columns
    """
    meta = MetaData()
    meta.bind = migrate_engine

    table = Table(table_name, meta, autoload=True)
    columns_for_group_by = [table.c[name] for name in uc_column_names]

    columns_for_select = [func.max(table.c.id)]
    columns_for_select.extend(columns_for_group_by)

    duplicated_rows_select = sqlalchemy.sql.select(
        columns_for_select, group_by=columns_for_group_by,
        having=func.count(table.c.id) > 1)

    for row in migrate_engine.execute(duplicated_rows_select):
        # NOTE(boris-42): Do not remove row that has the biggest ID.
        delete_condition = table.c.id != row[0]
        is_none = None  # workaround for pyflakes
        delete_condition &= table.c.deleted_at == is_none
        for name in uc_column_names:
            delete_condition &= table.c[name] == row[name]

        rows_to_delete_select = sqlalchemy.sql.select(
            [table.c.id]).where(delete_condition)
        for row in migrate_engine.execute(rows_to_delete_select).fetchall():
            LOG.info(_LI("Deleting duplicated row with id: %(id)s from table: "
                         "%(table)s") % dict(id=row[0], table=table_name))

        if use_soft_delete:
            delete_statement = table.update().\
                where(delete_condition).\
                values({
                    'deleted': literal_column('id'),
                    'updated_at': literal_column('updated_at'),
                    'deleted_at': timeutils.utcnow()
                })
        else:
            delete_statement = table.delete().where(delete_condition)
        migrate_engine.execute(delete_statement)
Ejemplo n.º 8
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    def stop(self):
        """Terminate child processes and wait on each."""
        self.running = False
        for pid in self.children:
            try:
                os.kill(pid, signal.SIGTERM)
            except OSError as exc:
                if exc.errno != errno.ESRCH:
                    raise

        # Wait for children to die
        if self.children:
            LOG.info(_LI("Waiting on %d children to exit"), len(self.children))
            while self.children:
                self._wait_child()
Ejemplo n.º 9
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    def _child_wait_for_exit_or_signal(self, launcher):
        status = 0
        signo = 0

        # NOTE(johannes): All exceptions are caught to ensure this
        # doesn't fallback into the loop spawning children. It would
        # be bad for a child to spawn more children.
        try:
            launcher.wait()
        except SignalExit as exc:
            signame = _signo_to_signame(exc.signo)
            LOG.info(_LI("Child caught %s, exiting"), signame)
            status = exc.code
            signo = exc.signo
        except SystemExit as exc:
            status = exc.code
        except BaseException:
            LOG.exception(_LE("Unhandled exception"))
            status = 2
        finally:
            launcher.stop()

        return status, signo
Ejemplo n.º 10
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    def _child_wait_for_exit_or_signal(self, launcher):
        status = 0
        signo = 0

        # NOTE(johannes): All exceptions are caught to ensure this
        # doesn't fallback into the loop spawning children. It would
        # be bad for a child to spawn more children.
        try:
            launcher.wait()
        except SignalExit as exc:
            signame = _signo_to_signame(exc.signo)
            LOG.info(_LI('Child caught %s, exiting'), signame)
            status = exc.code
            signo = exc.signo
        except SystemExit as exc:
            status = exc.code
        except BaseException:
            LOG.exception(_LE('Unhandled exception'))
            status = 2
        finally:
            launcher.stop()

        return status, signo
Ejemplo n.º 11
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    def launch_service(self, service, workers=1):
        wrap = ServiceWrapper(service, workers)

        LOG.info(_LI("Starting %d workers"), wrap.workers)
        while self.running and len(wrap.children) < wrap.workers:
            self._start_child(wrap)
Ejemplo n.º 12
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    def launch_service(self, service, workers=1):
        wrap = ServiceWrapper(service, workers)

        LOG.info(_LI('Starting %d workers'), wrap.workers)
        while self.running and len(wrap.children) < wrap.workers:
            self._start_child(wrap)