| # -*- coding: utf-8 -*- |
| # Copyright 2019 The Chromium OS Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| """Module containing methods and classes to interact with a nebraska instance. |
| """ |
| |
| from __future__ import print_function |
| |
| import os |
| import multiprocessing |
| |
| from six.moves import urllib |
| |
| from chromite.lib import constants |
| from chromite.lib import cros_build_lib |
| from chromite.lib import cros_logging as logging |
| from chromite.lib import remote_access |
| from chromite.lib import timeout_util |
| |
| |
| NEBRASKA_SOURCE_FILE = os.path.join(constants.SOURCE_ROOT, 'src', 'platform', |
| 'dev', 'nebraska', 'nebraska.py') |
| |
| # Error msg in loading shared libraries when running python command. |
| ERROR_MSG_IN_LOADING_LIB = 'error while loading shared libraries' |
| |
| class Error(Exception): |
| """Base exception class of nebraska errors.""" |
| |
| |
| class NebraskaStartupError(Error): |
| """Thrown when the nebraska fails to start up.""" |
| |
| |
| class NebraskaStopError(Error): |
| """Thrown when the nebraska fails to stop.""" |
| |
| |
| class RemoteNebraskaWrapper(multiprocessing.Process): |
| """A wrapper for nebraska.py on a remote device. |
| |
| We assume there is no chroot on the device, thus we do not launch |
| nebraska inside chroot. |
| """ |
| NEBRASKA_TIMEOUT = 30 |
| KILL_TIMEOUT = 10 |
| |
| # Keep in sync with nebraska.py if not passing these directly to nebraska. |
| RUNTIME_ROOT = '/run/nebraska' |
| PID_FILE_PATH = os.path.join(RUNTIME_ROOT, 'pid') |
| PORT_FILE_PATH = os.path.join(RUNTIME_ROOT, 'port') |
| LOG_FILE_PATH = '/tmp/nebraska.log' |
| REQUEST_LOG_FILE_PATH = '/tmp/nebraska_request_log.json' |
| |
| NEBRASKA_PATH = '/usr/local/bin/nebraska.py' |
| |
| def __init__(self, remote_device, nebraska_bin=None, |
| update_payloads_address=None, update_metadata_dir=None, |
| install_payloads_address=None, install_metadata_dir=None): |
| """Initializes the nebraska wrapper. |
| |
| Args: |
| remote_device: A remote_access.RemoteDevice object. |
| nebraska_bin: The path to the nebraska binary. |
| update_payloads_address: The root address where the payloads will be |
| served. it can either be a local address (file://) or a remote |
| address (http://) |
| update_metadata_dir: A directory where json files for payloads required |
| for update are located. |
| install_payloads_address: Same as update_payloads_address for install |
| operations. |
| install_metadata_dir: Similar to update_metadata_dir but for install |
| payloads. |
| """ |
| super(RemoteNebraskaWrapper, self).__init__() |
| |
| self._device = remote_device |
| self._hostname = remote_device.hostname |
| |
| self._update_payloads_address = update_payloads_address |
| self._update_metadata_dir = update_metadata_dir |
| self._install_payloads_address = install_payloads_address |
| self._install_metadata_dir = install_metadata_dir |
| |
| self._nebraska_bin = nebraska_bin or self.NEBRASKA_PATH |
| |
| self._port_file = self.PORT_FILE_PATH |
| self._pid_file = self.PID_FILE_PATH |
| self._log_file = self.LOG_FILE_PATH |
| |
| self._port = None |
| self._pid = None |
| |
| def _RemoteCommand(self, *args, **kwargs): |
| """Runs a remote shell command. |
| |
| Args: |
| *args: See remote_access.RemoteDevice documentation. |
| **kwargs: See remote_access.RemoteDevice documentation. |
| """ |
| kwargs.setdefault('debug_level', logging.DEBUG) |
| return self._device.RunCommand(*args, **kwargs) |
| |
| def _PortFileExists(self): |
| """Checks whether the port file exists in the remove device or not.""" |
| result = self._RemoteCommand( |
| ['test', '-f', self._port_file], error_code_ok=True) |
| return result.returncode == 0 |
| |
| def _ReadPortNumber(self): |
| """Reads the port number from the port file on the remote device.""" |
| if not self.is_alive(): |
| raise NebraskaStartupError('Nebraska is not alive, so no port file yet!') |
| |
| try: |
| timeout_util.WaitForReturnTrue(self._PortFileExists, period=5, |
| timeout=self.NEBRASKA_TIMEOUT) |
| except timeout_util.TimeoutError: |
| self.terminate() |
| raise NebraskaStartupError('Timeout (%s) waiting for remote nebraska' |
| ' port_file' % self.NEBRASKA_TIMEOUT) |
| |
| self._port = int(self._RemoteCommand( |
| ['cat', self._port_file], capture_output=True).output.strip()) |
| |
| def IsReady(self): |
| """Returns True if nebraska is ready to accept requests.""" |
| if not self.is_alive(): |
| raise NebraskaStartupError('Nebraska is not alive, so not ready!') |
| |
| url = 'http://%s:%d/%s' % (remote_access.LOCALHOST_IP, self._port, |
| 'check_health') |
| # Running curl through SSH because the port on the device is not accessible |
| # by default. |
| result = self._RemoteCommand( |
| ['curl', url, '-o', '/dev/null'], error_code_ok=True) |
| return result.returncode == 0 |
| |
| def _WaitUntilStarted(self): |
| """Wait until the nebraska has started.""" |
| if not self._port: |
| self._ReadPortNumber() |
| |
| try: |
| timeout_util.WaitForReturnTrue(self.IsReady, |
| timeout=self.NEBRASKA_TIMEOUT, |
| period=5) |
| except timeout_util.TimeoutError: |
| raise NebraskaStartupError('Nebraska did not start.') |
| |
| self._pid = int(self._RemoteCommand( |
| ['cat', self._pid_file], capture_output=True).output.strip()) |
| logging.info('Started nebraska with pid %s', self._pid) |
| |
| def run(self): |
| """Launches a nebraska process on the device. |
| |
| Starts a background nebraska and waits for it to finish. |
| """ |
| logging.info('Starting nebraska on %s', self._hostname) |
| |
| if not self._update_metadata_dir: |
| raise NebraskaStartupError( |
| 'Update metadata directory location is not passed.') |
| |
| cmd = [ |
| 'python', self._nebraska_bin, |
| '--update-metadata', self._update_metadata_dir, |
| ] |
| |
| if self._update_payloads_address: |
| cmd += ['--update-payloads-address', self._update_payloads_address] |
| if self._install_metadata_dir: |
| cmd += ['--install-metadata', self._install_metadata_dir] |
| if self._install_payloads_address: |
| cmd += ['--install-payloads-address', self._install_payloads_address] |
| |
| try: |
| self._RemoteCommand(cmd, redirect_stdout=True, combine_stdout_stderr=True) |
| except cros_build_lib.RunCommandError as err: |
| msg = 'Remote nebraska failed (to start): %s' % str(err) |
| logging.error(msg) |
| raise NebraskaStartupError(msg) |
| |
| def Start(self): |
| """Starts the nebraska process remotely on the remote device.""" |
| if self.is_alive(): |
| logging.warn('Nebraska is already running, not running again.') |
| return |
| |
| self.start() |
| self._WaitUntilStarted() |
| |
| def Stop(self): |
| """Stops the nebraska instance if its running. |
| |
| Kills the nebraska instance with SIGTERM (and SIGKILL if SIGTERM fails). |
| """ |
| logging.debug('Stopping nebraska instance with pid %s', self._pid) |
| if self.is_alive(): |
| self._RemoteCommand(['kill', str(self._pid)], error_code_ok=True) |
| else: |
| logging.debug('Nebraska is not running, stopping nothing!') |
| return |
| |
| self.join(self.KILL_TIMEOUT) |
| if self.is_alive(): |
| logging.warning('Nebraska is unstoppable. Killing with SIGKILL.') |
| try: |
| self._RemoteCommand(['kill', '-9', str(self._pid)]) |
| except cros_build_lib.RunCommandError as e: |
| raise NebraskaStopError('Unable to stop Nebraska: %s' % e) |
| |
| def GetURL(self, ip=remote_access.LOCALHOST_IP, |
| critical_update=False, no_update=False): |
| """Returns the URL which the devserver is running on. |
| |
| Args: |
| ip: The ip of running nebraska if different than localhost. |
| critical_update: Whether nebraska has to instruct the update_engine that |
| the update is a critical one or not. |
| no_update: Whether nebraska has to give a noupdate response even if it |
| detected an update. |
| |
| Returns: |
| An HTTP URL that can be passed to the update_engine_client in --omaha_url |
| flag. |
| """ |
| query_dict = {} |
| if critical_update: |
| query_dict['critical_update'] = True |
| if no_update: |
| query_dict['no_update'] = True |
| query_string = urllib.parse.urlencode(query_dict) |
| |
| return ('http://%s:%d/update/%s' % |
| (ip, self._port, (('?%s' % query_string) if query_string else ''))) |
| |
| def PrintLog(self): |
| """Print Nebraska log to stdout.""" |
| if self._RemoteCommand( |
| ['test', '-f', self._log_file], error_code_ok=True).returncode != 0: |
| logging.error('Nebraska log file %s does not exist on the device.', |
| self._log_file) |
| return |
| |
| result = self._RemoteCommand(['cat', self._log_file], capture_output=True) |
| output = '--- Start output from %s ---\n' % self._log_file |
| output += result.output |
| output += '--- End output from %s ---' % self._log_file |
| return output |
| |
| def CollectLogs(self, target_log): |
| """Copies the nebraska logs from the device. |
| |
| Args: |
| target_log: The file to copy the log to from the device. |
| """ |
| try: |
| self._device.CopyFromDevice(self._log_file, target_log) |
| except (remote_access.RemoteAccessException, |
| cros_build_lib.RunCommandError) as err: |
| logging.error('Failed to copy nebraska logs from device, ignoring: %s', |
| str(err)) |
| |
| def CollectRequestLogs(self, target_log): |
| """Copies the nebraska logs from the device. |
| |
| Args: |
| target_log: The file to write the log to. |
| """ |
| if not self.is_alive(): |
| return |
| |
| request_log_url = 'http://%s:%d/requestlog' % (remote_access.LOCALHOST_IP, |
| self._port) |
| try: |
| self._RemoteCommand( |
| ['curl', request_log_url, '-o', self.REQUEST_LOG_FILE_PATH]) |
| self._device.CopyFromDevice(self.REQUEST_LOG_FILE_PATH, target_log) |
| except (remote_access.RemoteAccessException, |
| cros_build_lib.RunCommandError) as err: |
| logging.error('Failed to get requestlog from nebraska. ignoring: %s', |
| str(err)) |
| |
| def CheckNebraskaCanRun(self): |
| """Checks to see if we can start nebraska. |
| |
| If the stateful partition is corrupted, Python or other packages needed for |
| rootfs update may be missing on |device|. |
| |
| This will also use `ldconfig` to update library paths on the target |
| device if it looks like that's causing problems, which is necessary |
| for base images. |
| |
| Raise NebraskaStartupError if nebraska cannot start. |
| """ |
| |
| # Try to capture the output from the command so we can dump it in the case |
| # of errors. Note that this will not work if we were requested to redirect |
| # logs to a |log_file|. |
| cmd_kwargs = {'capture_output': True, 'combine_stdout_stderr': True} |
| cmd = ['python', self._nebraska_bin, '--help'] |
| logging.info('Checking if we can run nebraska on the device...') |
| try: |
| self._RemoteCommand(cmd, **cmd_kwargs) |
| except cros_build_lib.RunCommandError as e: |
| logging.warning('Cannot start nebraska.') |
| logging.warning(e.result.error) |
| if ERROR_MSG_IN_LOADING_LIB in str(e): |
| logging.info('Attempting to correct device library paths...') |
| try: |
| self._RemoteCommand(['ldconfig'], **cmd_kwargs) |
| self._RemoteCommand(cmd, **cmd_kwargs) |
| logging.info('Library path correction successful.') |
| return |
| except cros_build_lib.RunCommandError as e2: |
| logging.warning('Library path correction failed:') |
| logging.warning(e2.result.error) |
| raise NebraskaStartupError(e.result.error) |
| |
| raise NebraskaStartupError(str(e)) |
