Source code for pylorax.monitor

# monitor.py
#
# Copyright (C) 2011-2015  Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Author(s): Brian C. Lane <bcl@redhat.com>
#
import logging
log = logging.getLogger("livemedia-creator")

import re
import socket
import socketserver
import threading
import time

[docs] class LogRequestHandler(socketserver.BaseRequestHandler): """ Handle monitoring and saving the logfiles from the virtual install Incoming data is written to self.server.log_path and each line is checked for patterns that would indicate that the installation failed. self.server.log_error is set True when this happens. """ simple_tests = [ "Traceback (", "traceback script(s) have been run", "Out of memory:", "Call Trace:", "insufficient disk space:", "Not enough disk space to download the packages", "error populating transaction after", "crashed on signal", "packaging: Missed: NoSuchPackage", "packaging: Installation failed", "The following error occurred while installing. This is a fatal error", "Error in POSTIN scriptlet in rpm package" ] re_tests = [ r"Process [0-9]+ \(anaconda\) of user [0-9]+ dumped core", r"packaging: base repo (?!\(CDROM/file).* not valid", r"packaging: .* requires .*" ]
[docs] def setup(self): """Start writing to self.server.log_path""" if self.server.log_path: self.fp = open(self.server.log_path, "w") # pylint: disable=attribute-defined-outside-init else: self.fp = None self.request.settimeout(10)
[docs] def handle(self): """ Write incoming data to a logfile and check for errors Split incoming data into lines and check for any Tracebacks or other errors that indicate that the install failed. Loops until self.server.kill is True """ log.info("Processing logs from %s", self.client_address) data = b"" while True: if self.server.kill: break try: data += self.request.recv(4096) for line in data.splitlines(keepends=True): if line.endswith(b"\n"): # Ignore invalid UTF8 inside lines self.iserror(str(line[:-1], "utf8", "ignore")) if self.fp: self.fp.write(str(line, "utf8", "ignore")) self.fp.flush() data = b"" else: # Not the end of the line, keep for later data = line break except socket.timeout: pass except Exception as e: # pylint: disable=broad-except log.info("log processing killed by exception: %s", e) break
[docs] def finish(self): log.info("Shutting down log processing") if self.fp: self.fp.close()
[docs] def iserror(self, line): """ Check a line to see if it contains an error indicating installation failure :param str line: log line to check for failure If the line contains IGNORED it will be skipped. """ if "IGNORED" in line: return for t in self.simple_tests: if t in line: self.server.log_error = True self.server.error_line = line return for t in self.re_tests: if re.search(t, line): self.server.log_error = True self.server.error_line = line return
[docs] class LogServer(socketserver.TCPServer): """A TCP Server that listens for log data""" # Number of seconds to wait for a connection after startup timeout = 60 def __init__(self, log_path, *args, **kwargs): """ Setup the log server :param str log_path: Path to the log file to write """ self.kill = False self.log_error = False self.error_line = "" self.log_path = log_path self._timeout = kwargs.pop("timeout", None) if self._timeout: self._start_time = time.time() socketserver.TCPServer.__init__(self, *args, **kwargs)
[docs] def log_check(self): """ Check to see if an error has been found in the log :returns: True if there has been an error :rtype: bool """ if self._timeout: taking_too_long = time.time() > self._start_time + (self._timeout * 60) if taking_too_long: log.error("Canceling installation due to timeout") else: taking_too_long = False return self.log_error or taking_too_long
[docs] class LogMonitor(object): """ Setup a server to monitor the logs output by the installation This needs to be running before the virt-install runs, it expects there to be a listener on the port used for the virtio log port. """ def __init__(self, log_path=None, host="localhost", port=0, timeout=None, log_request_handler_class=LogRequestHandler): """ Start a thread to monitor the logs. :param str log_path: Path to the logfile to write :param str host: Host to bind to. Default is localhost. :param int port: Port to listen to or 0 to pick a port If 0 is passed for the port the dynamically assigned port will be available as self.port If log_path isn't set then it only monitors the logs, instead of also writing them to disk. """ self.server = LogServer(log_path, (host, port), log_request_handler_class, timeout=timeout) self.host, self.port = self.server.server_address self.log_path = log_path self.server_thread = threading.Thread(target=self.server.handle_request) self.server_thread.daemon = True self.server_thread.start()
[docs] def shutdown(self): """Force shutdown of the monitoring thread""" self.server.kill = True self.server_thread.join() self.server.server_close()