From 4446e4642ec652eaa4169c3fa10771d1c778a8f9 Mon Sep 17 00:00:00 2001 From: Kevin Carter Date: Thu, 27 Nov 2014 10:47:33 -0600 Subject: [PATCH 1/2] Added new module to support LXC containers The new module will allow users to control LXC containers from ansible. The module was built for use in LXC >= 1.0 or greater and implements most of what can be done using the various lxc clients with regards to running containers. This first module is geared only at managing lxc containers. The module provides: build containers destroy containers archive containers info from a single container start / stop / restart containers run commands within containers add/modify lxc config for a container supports backends including LVM --- cloud/lxc/__init__.py | 0 cloud/lxc/lxc-container.py | 1469 ++++++++++++++++++++++++++++++++++++ 2 files changed, 1469 insertions(+) create mode 100644 cloud/lxc/__init__.py create mode 100644 cloud/lxc/lxc-container.py diff --git a/cloud/lxc/__init__.py b/cloud/lxc/__init__.py new file mode 100644 index 00000000000..e69de29bb2d diff --git a/cloud/lxc/lxc-container.py b/cloud/lxc/lxc-container.py new file mode 100644 index 00000000000..b72890972db --- /dev/null +++ b/cloud/lxc/lxc-container.py @@ -0,0 +1,1469 @@ +#!/usr/bin/python +# -*- coding: utf-8 -*- + +# (c) 2014, Kevin Carter +# +# This file is part of Ansible +# +# Ansible 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 3 of the License, or +# (at your option) any later version. +# +# Ansible 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 Ansible. If not, see . + + +DOCUMENTATION = """ +--- +module: lxc-container +short_description: Manage LXC Containers +version_added: 1.8.0 +description: + - Management of LXC containers +author: Kevin Carter +options: + name: + description: + - Name of a container. + required: true + backing_store: + choices: + - dir + - lvm + - loop + - btrfs + description: + - Backend storage type for the container. + required: false + default: dir + template: + description: + - Name of the template to use within an LXC create. + required: false + default: ubuntu + template_options: + description: + - Template options when building the container. + required: false + config: + description: + - Path to the LXC configuration file. + required: false + default: /etc/lxc/default.conf + lv_name: + description: + - Name of the logical volume, defaults to the container name. + default: $CONTAINER_NAME + required: false + vg_name: + description: + - If Backend store is lvm, specify the name of the volume group. + default: lxc + required: false + thinpool: + description: + - Use LVM thin pool called TP. + required: false + fs_type: + description: + - Create fstype TYPE. + default: ext4 + required: false + fs_size: + description: + - File system Size. + default: 5G + required: false + directory: + description: + - Place rootfs directory under DIR. + required: false + zfs_root: + description: + - Create zfs under given zfsroot. + required: false + container_command: + description: + - Run a command within a container. + required: false + lxc_path: + description: + - Place container under PATH + required: false + container_log: + choices: + - true + - false + description: + - Enable a container log for host actions to the container. + default: false + container_log_level: + choices: + - INFO + - ERROR + - DEBUG + description: + - Set the log level for a container where *container_log* was set. + required: false + default: INFO + archive: + choices: + - true + - false + description: + - Create an archive of a container. This will create a tarball of the + running container. + default: false + archive_path: + description: + - Path the save the archived container. If the path does not exist + the archive method will attempt to create it. + default: /tmp + archive_compression: + choices: + - gzip + - bzip2 + - none + description: + - Type of compression to use when creating an archive of a running + container. + default: gzip + state: + choices: + - started + - stopped + - restarted + - absent + - frozen + description: + - Start a container right after it's created. + required: false + default: started + container_config: + description: + - list of 'key=value' options to use when configuring a container. + required: false +requirements: ['lxc >= 1.0', 'python2-lxc >= 0.1'] +notes: + - Containers must have a unique name. If you attempt to create a container + with a name that already exists in the users namespace the module will + simply return as "unchanged". + - The "container_command" can be used with any state except "absent". If + used with state "stopped" the container will be "started", the command + executed, and then the container "stopped" again. Likewise if the state + is "stopped" and the container does not exist it will be first created, + "started", the command executed, and then "stopped". If you use a "|" + in the variable you can use common script formatting within the variable + iteself The "container_command" option will always execute as BASH. + When using "container_command" a log file is created in the /tmp/ directory + which contains both stdout and stderr of any command executed. + - If "archive" is **true** the system will attempt to create a compressed + tarball of the running container. The "archive" option supports LVM backed + containers and will create a snapshot of the running container when + creating the archive. + - If your distro does not have a package for "python2-lxc", which is a + requirement for this module, it can be installed from source at + "https://github.com/lxc/python2-lxc" +""" + +EXAMPLES = """ +- name: Create a started container + lxc-container: + name: test-container-started + container_log: true + template: ubuntu + state: started + template_options: --release trusty + +- name: Create a stopped container + lxc-container: + name: test-container-stopped + container_log: true + template: ubuntu + state: stopped + template_options: --release trusty + +- name: Create a frozen container + lxc-container: + name: test-container-frozen + container_log: true + template: ubuntu + state: frozen + template_options: --release trusty + container_command: | + echo 'hello world.' | tee /opt/started-frozen + +# Create filesystem container, configure it, and archive it, and start it. +- name: Create filesystem container + lxc-container: + name: test-container-config + container_log: true + template: ubuntu + state: started + archive: true + archive_compression: none + container_config: + - "lxc.aa_profile=unconfined" + - "lxc.cgroup.devices.allow=a *:* rmw" + template_options: --release trusty + +# Create an lvm container, run a complex command in it, add additional +# configuration to it, create an archive of it, and finally leave the container +# in a frozen state. The container archive will be compressed using bzip2 +- name: Create an lvm container + lxc-container: + name: test-container-lvm + container_log: true + template: ubuntu + state: frozen + backing_store: lvm + template_options: --release trusty + container_command: | + apt-get update + apt-get install -y vim lxc-dev + echo 'hello world.' | tee /opt/started + if [[ -f "/opt/started" ]]; then + echo 'hello world.' | tee /opt/found-started + fi + container_config: + - "lxc.aa_profile=unconfined" + - "lxc.cgroup.devices.allow=a *:* rmw" + archive: true + archive_compression: bzip2 + register: lvm_container_info + +- name: Debug info on container "test-container-lvm" + debug: var=lvm_container_info + +- name: Get information on a given container. + lxc-container: + name: test-container-config + register: config_container_info + +- name: debug info on container "test-container" + debug: var=config_container_info + +- name: Run a command in a container and ensure its in a "stopped" state. + lxc-container: + name: test-container-started + state: stopped + container_command: | + echo 'hello world.' | tee /opt/stopped + +- name: Run a command in a container and ensure its it in a "frozen" state. + lxc-container: + name: test-container-stopped + state: frozen + container_command: | + echo 'hello world.' | tee /opt/frozen + +- name: Start a container. + lxc-container: + name: test-container-stopped + state: started + +- name: Run a command in a container and then restart it. + lxc-container: + name: test-container-started + state: restarted + container_command: | + echo 'hello world.' | tee /opt/restarted + +- name: Run a complex command within a "running" container. + lxc-container: + name: test-container-started + container_command: | + apt-get update + apt-get install -y curl wget vim apache2 + echo 'hello world.' | tee /opt/started + if [[ -f "/opt/started" ]]; then + echo 'hello world.' | tee /opt/found-started + fi + +# Create an archive of an existing container, save the archive to a defined +# path and then destroy it. +- name: Archive container + lxc-container: + name: test-container-started + state: absent + archive: true + archive_path: /opt/archives + +- name: Destroy a container. + lxc-container: + name: "{{ item }}" + state: absent + with_items: + - test-container-stopped + - test-container-started + - test-container-frozen + - test-container-lvm + - test-container-config +""" + + +try: + import lxc +except ImportError: + msg = 'The lxc module is not importable. Check the requirements.' + print("failed=True msg='%s'" % msg) + raise SystemExit(msg) + + +# LXC_COMPRESSION_MAP is a map of available compression types when creating +# an archive of a container. +LXC_COMPRESSION_MAP = { + 'gzip': { + 'extension': 'tar.tgz', + 'argument': '-czf' + }, + 'bzip2': { + 'extension': 'tar.bz2', + 'argument': '-cjf' + }, + 'none': { + 'extension': 'tar', + 'argument': '-cf' + } +} + + +# LXC_COMMAND_MAP is a map of variables that are available to a method based +# on the state the container is in. +LXC_COMMAND_MAP = { + 'create': { + 'variables': { + 'config': '--config', + 'template': '--template', + 'backing_store': '--bdev', + 'lxc_path': '--lxcpath', + 'lv_name': '--lvname', + 'vg_name': '--vgname', + 'thinpool': '--thinpool', + 'fs_type': '--fstype', + 'fs_size': '--fssize', + 'directory': '--dir', + 'zfs_root': '--zfsroot' + } + } +} + + +# LXC_BACKING_STORE is a map of available storage backends and options that +# are incompatible with the given storage backend. +LXC_BACKING_STORE = { + 'dir': [ + 'lv_name', 'vg_name', 'fs_type', 'fs_size', 'thinpool' + ], + 'lvm': [ + 'zfs_root' + ], + 'btrfs': [ + 'lv_name', 'vg_name', 'thinpool', 'zfs_root' + ], + 'loop': [ + 'lv_name', 'vg_name', 'thinpool', 'zfs_root' + ] +} + + +# LXC_LOGGING_LEVELS is a map of available log levels +LXC_LOGGING_LEVELS = { + 'INFO': ['info', 'INFO', 'Info'], + 'ERROR': ['error', 'ERROR', 'Error'], + 'DEBUG': ['debug', 'DEBUG', 'Debug'] +} + + +# LXC_ANSIBLE_STATES is a map of states that contain values of methods used +# when a particular state is evoked. +LXC_ANSIBLE_STATES = { + 'started': '_started', + 'stopped': '_stopped', + 'restarted': '_restarted', + 'absent': '_destroyed', + 'frozen': '_frozen' +} + + +# This is used to attach to a running container and execute commands from +# within the container on the host. This will provide local access to a +# container without using SSH. The template will attempt to work within the +# home directory of the user that was attached to the container and source +# that users environment variables by default. +ATTACH_TEMPLATE = """#!/usr/bin/env bash +pushd "$(grep $(whoami) /etc/passwd | awk -F':' '{print $6}')" + if [[ -f ".bashrc" ]];then + source .bashrc + fi +popd + +# User defined command +%(container_command)s +""" + + +def create_script(command): + """Write out a script onto a target. + + This method should be backward compatible with Python 2.4+ when executing + from within the container. + + :param command: command to run, this can be a script and can use spacing + with newlines as separation. + :type command: ``str`` + """ + + import os + import os.path as path + import subprocess + import tempfile + + # Ensure that the directory /opt exists. + if not path.isdir('/opt'): + os.mkdir('/opt') + + # Create the script. + script_file = path.join('/opt', '.lxc-attach-script') + f = open(script_file, 'wb') + try: + f.write(ATTACH_TEMPLATE % {'container_command': command}) + f.flush() + finally: + f.close() + + # Ensure the script is executable. + os.chmod(script_file, 0755) + + # Get temporary directory. + tempdir = tempfile.gettempdir() + + # Output log file. + stdout = path.join(tempdir, 'lxc-attach-script.log') + stdout_file = open(stdout, 'ab') + + # Error log file. + stderr = path.join(tempdir, 'lxc-attach-script.err') + stderr_file = open(stderr, 'ab') + + # Execute the script command. + try: + subprocess.Popen( + [script_file], + stdout=stdout_file, + stderr=stderr_file + ).communicate() + finally: + # Close the log files. + stderr_file.close() + stdout_file.close() + + # Remove the script file upon completion of execution. + os.remove(script_file) + + +class LxcContainerManagement(object): + def __init__(self, module): + """Management of LXC containers via Ansible. + + :param module: Processed Ansible Module. + :type module: ``object`` + """ + self.module = module + self.state = self.module.params.get('state', None) + self.state_change = False + self.lxc_vg = None + self.container_name = self.module.params['name'] + self.container = self.get_container_bind() + self.archive_info = None + + def get_container_bind(self): + return lxc.Container(name=self.container_name) + + @staticmethod + def _roundup(num): + """Return a rounded floating point number. + + :param num: Number to round up. + :type: ``float`` + :returns: Rounded up number. + :rtype: ``int`` + """ + num, part = str(num).split('.') + num = int(num) + if int(part) != 0: + num += 1 + return num + + @staticmethod + def _container_exists(name): + """Check if a container exists. + + :param name: Name of the container. + :type: ``str`` + :returns: True or False if the container is found. + :rtype: ``bol`` + """ + if [i for i in lxc.list_containers() if i == name]: + return True + else: + return False + + @staticmethod + def _add_variables(variables_dict, build_command): + """Return a command list with all found options. + + :param variables_dict: Pre-parsed optional variables used from a + seed command. + :type variables_dict: ``dict`` + :param build_command: Command to run. + :type build_command: ``list`` + :returns: list of command options. + :rtype: ``list`` + """ + + for key, value in variables_dict.items(): + build_command.append( + '%s %s' % (key, value) + ) + else: + return build_command + + def _get_vars(self, variables): + """Return a dict of all variables as found within the module. + + :param variables: Hash of all variables to find. + :type variables: ``dict`` + """ + + # Remove incompatible storage backend options. + for v in LXC_BACKING_STORE[self.module.params['backing_store']]: + variables.pop(v, None) + + return_dict = dict() + for k, v in variables.items(): + _var = self.module.params.get(k) + if not [i for i in [None, ''] + BOOLEANS_FALSE if i == _var]: + return_dict[v] = _var + else: + return return_dict + + def _run_command(self, build_command, unsafe_shell=False, timeout=600): + """Return information from running an Ansible Command. + + This will squash the build command list into a string and then + execute the command via Ansible. The output is returned to the method. + This output is returned as `return_code`, `stdout`, `stderr`. + + Prior to running the command the method will look to see if the LXC + lockfile is present. If the lockfile "/var/lock/subsys/lxc" the method + will wait upto 10 minutes for it to be gone; polling every 5 seconds. + + :param build_command: Used for the command and all options. + :type build_command: ``list`` + :param unsafe_shell: Enable or Disable unsafe sell commands. + :type unsafe_shell: ``bol`` + :param timeout: Time before the container create process quites. + :type timeout: ``int`` + """ + + lockfile = '/var/lock/subsys/lxc' + + for _ in xrange(timeout): + if os.path.exists(lockfile): + time.sleep(1) + else: + return self.module.run_command( + ' '.join(build_command), + use_unsafe_shell=unsafe_shell + ) + else: + message = ( + 'The LXC subsystem is locked and after 5 minutes it never' + ' became unlocked. Lockfile [ %s ]' % lockfile + ) + self.failure( + error='LXC subsystem locked', + rc=0, + msg=message + ) + + def _config(self): + """Configure an LXC container. + + Write new configuration values to the lxc config file. This will + stop the container if it's running write the new options and then + restart the container upon completion. + """ + + _container_config = self.module.params.get('container_config') + if not _container_config: + return False + + container_config_file = self.container.config_file_name + with open(container_config_file, 'rb') as f: + container_config = f.readlines() + + # Note used ast literal_eval because AnsibleModule does not provide for + # adequate dictionary parsing. + # Issue: https://github.com/ansible/ansible/issues/7679 + # TODO(cloudnull) adjust import when issue has been resolved. + import ast + options_dict = ast.literal_eval(_container_config) + parsed_options = [i.split('=') for i in options_dict] + + config_change = False + for key, value in parsed_options: + new_entry = '%s = %s\n' % (key, value) + for option_line in container_config: + # Look for key in config + if option_line.startswith(key): + _, _value = option_line.split('=') + config_value = ' '.join(_value.split()) + line_index = container_config.index(option_line) + # If the sanitized values don't match replace them + if value != config_value: + line_index += 1 + if new_entry not in container_config: + config_change = True + container_config.insert(line_index, new_entry) + # Break the flow as values are written or not at this point + break + else: + config_change = True + container_config.append(new_entry) + + # If the config changed restart the container. + if config_change: + container_state = self._get_state() + if container_state != 'stopped': + self.container.stop() + + with open(container_config_file, 'wb') as f: + f.writelines(container_config) + + self.state_change = True + if container_state == 'running': + self._container_startup() + elif container_state == 'frozen': + self._container_startup() + self.container.freeze() + + def _create(self): + """Create a new LXC container. + + This method will build and execute a shell command to build the + container. It would have been nice to simply use the lxc python library + however at the time this was written the python library, in both py2 + and py3 didn't support some of the more advanced container create + processes. These missing processes mainly revolve around backing + LXC containers with block devices. + """ + + build_command = [ + self.module.get_bin_path('lxc-create', True), + '--name %s' % self.container_name, + '--quiet' + ] + + build_command = self._add_variables( + variables_dict=self._get_vars( + variables=LXC_COMMAND_MAP['create']['variables'] + ), + build_command=build_command + ) + + # Load logging for the instance when creating it. + if self.module.params.get('container_log') in BOOLEANS_TRUE: + # Set the logging path to the /var/log/lxc if uid is root. else + # set it to the home folder of the user executing. + try: + if os.getuid() != 0: + log_path = os.getenv('HOME') + else: + if not os.path.isdir('/var/log/lxc/'): + os.makedirs('/var/log/lxc/') + log_path = '/var/log/lxc/' + except OSError: + log_path = os.getenv('HOME') + + build_command.extend([ + '--logfile %s' % os.path.join( + log_path, 'lxc-%s.log' % self.container_name + ), + '--logpriority %s' % self.module.params.get( + 'container_log_level' + ).upper() + ]) + + # Add the template commands to the end of the command if there are any + template_options = self.module.params.get('template_options', None) + if template_options: + build_command.append('-- %s' % template_options) + + rc, return_data, err = self._run_command(build_command) + if rc != 0: + msg = "Failed executing lxc-create." + self.failure( + err=err, rc=rc, msg=msg, command=' '.join(build_command) + ) + else: + self.state_change = True + + def _container_data(self): + """Returns a dict of container information. + + :returns: container data + :rtype: ``dict`` + """ + + return { + 'interfaces': self.container.get_interfaces(), + 'ips': self.container.get_ips(), + 'state': self._get_state(), + 'init_pid': int(self.container.init_pid) + } + + def _unfreeze(self): + """Unfreeze a container. + + :returns: True or False based on if the container was unfrozen. + :rtype: ``bol`` + """ + + unfreeze = self.container.unfreeze() + if unfreeze: + self.state_change = True + return unfreeze + + def _get_state(self): + """Return the state of a container. + + If the container is not found the state returned is "absent" + + :returns: state of a container as a lower case string. + :rtype: ``str`` + """ + + if self._container_exists(name=self.container_name): + return str(self.container.state).lower() + else: + return str('absent') + + def _execute_command(self): + """Execute a shell command.""" + + container_command = self.module.params.get('container_command') + if container_command: + container_state = self._get_state() + if container_state == 'frozen': + self._unfreeze() + elif container_state == 'stopped': + self._container_startup() + + self.container.attach_wait(create_script, container_command) + self.state_change = True + + def _container_startup(self, timeout=60): + """Ensure a container is started. + + :param timeout: Time before the destroy operation is abandoned. + :type timeout: ``int`` + """ + + self.container = self.get_container_bind() + for _ in xrange(timeout): + if self._get_state() != 'running': + self.container.start() + self.state_change = True + # post startup sleep for 1 second. + time.sleep(1) + else: + return True + else: + self.failure( + lxc_container=self._container_data(), + error='Failed to start container' + ' [ %s ]' % self.container_name, + rc=1, + msg='The container [ %s ] failed to start. Check to lxc is' + ' available and that the container is in a functional' + ' state.' + ) + + def _check_archive(self): + """Create a compressed archive of a container. + + This will store archive_info in as self.archive_info + """ + + if self.module.params.get('archive') in BOOLEANS_TRUE: + self.archive_info = { + 'archive': self._container_create_tar() + } + + def _destroyed(self, timeout=60): + """Ensure a container is destroyed. + + :param timeout: Time before the destroy operation is abandoned. + :type timeout: ``int`` + """ + + for _ in xrange(timeout): + if not self._container_exists(name=self.container_name): + break + + # Check if the container needs to have an archive created. + self._check_archive() + + if self._get_state() != 'stopped': + self.state_change = True + self.container.stop() + + if self.container.destroy(): + self.state_change = True + + # post destroy attempt sleep for 1 second. + time.sleep(1) + else: + self.failure( + lxc_container=self._container_data(), + error='Failed to destroy container' + ' [ %s ]' % self.container_name, + rc=1, + msg='The container [ %s ] failed to be destroyed. Check' + ' that lxc is available and that the container is in a' + ' functional state.' % self.container_name + ) + + def _frozen(self, count=0): + """Ensure a container is frozen. + + If the container does not exist the container will be created. + + :param count: number of times this command has been called by itself. + :type count: ``int`` + """ + + self.check_count(count=count, method='frozen') + if self._container_exists(name=self.container_name): + self._execute_command() + + # Perform any configuration updates + self._config() + + container_state = self._get_state() + if container_state == 'frozen': + pass + elif container_state == 'running': + self.container.freeze() + self.state_change = True + else: + self._container_startup() + self.container.freeze() + self.state_change = True + + # Check if the container needs to have an archive created. + self._check_archive() + else: + self._create() + count += 1 + self._frozen(count) + + def _restarted(self, count=0): + """Ensure a container is restarted. + + If the container does not exist the container will be created. + + :param count: number of times this command has been called by itself. + :type count: ``int`` + """ + + self.check_count(count=count, method='restart') + if self._container_exists(name=self.container_name): + self._execute_command() + + # Perform any configuration updates + self._config() + + if self._get_state() != 'stopped': + self.container.stop() + self.state_change = True + + # Check if the container needs to have an archive created. + self._check_archive() + else: + self._create() + count += 1 + self._restarted(count) + + def _stopped(self, count=0): + """Ensure a container is stopped. + + If the container does not exist the container will be created. + + :param count: number of times this command has been called by itself. + :type count: ``int`` + """ + + self.check_count(count=count, method='stop') + if self._container_exists(name=self.container_name): + self._execute_command() + + # Perform any configuration updates + self._config() + + if self._get_state() != 'stopped': + self.container.stop() + self.state_change = True + + # Check if the container needs to have an archive created. + self._check_archive() + else: + self._create() + count += 1 + self._stopped(count) + + def _started(self, count=0): + """Ensure a container is started. + + If the container does not exist the container will be created. + + :param count: number of times this command has been called by itself. + :type count: ``int`` + """ + + self.check_count(count=count, method='start') + if self._container_exists(name=self.container_name): + container_state = self._get_state() + if container_state == 'running': + pass + elif container_state == 'frozen': + self._unfreeze() + elif not self._container_startup(): + self.failure( + lxc_container=self._container_data(), + error='Failed to start container' + ' [ %s ]' % self.container_name, + rc=1, + msg='The container [ %s ] failed to start. Check to lxc is' + ' available and that the container is in a functional' + ' state.' % self.container_name + ) + + # Return data + self._execute_command() + + # Perform any configuration updates + self._config() + + # Check if the container needs to have an archive created. + self._check_archive() + else: + self._create() + count += 1 + self._started(count) + + def _get_lxc_vg(self): + """Return the name of the Volume Group used in LXC.""" + + build_command = [ + self.module.get_bin_path('lxc-config', True), + "lxc.bdev.lvm.vg" + ] + rc, vg, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='Failed to read LVM VG from LXC config', + command=' '.join(build_command) + ) + else: + return str(vg.strip()) + + def _lvm_lv_list(self): + """Return a list of all lv in a current vg.""" + + vg = self._get_lxc_vg() + build_command = [ + self.module.get_bin_path('lvs', True) + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='Failed to get list of LVs', + command=' '.join(build_command) + ) + + all_lvms = [i.split() for i in stdout.splitlines()][1:] + return [lv_entry[0] for lv_entry in all_lvms if lv_entry[1] == vg] + + def _get_vg_free_pe(self, name): + """Return the available size of a given VG. + + :param name: Name of volume. + :type name: ``str`` + :returns: size and measurement of an LV + :type: ``tuple`` + """ + build_command = [ + 'vgdisplay', + name + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to read vg %s' % name, + command=' '.join(build_command) + ) + + vg_info = [i.strip() for i in stdout.splitlines()][1:] + free_pe = [i for i in vg_info if i.startswith('Free')] + _free_pe = free_pe[0].split() + return float(_free_pe[-2]), _free_pe[-1] + + def _get_lv_size(self, name): + """Return the available size of a given LV. + + :param name: Name of volume. + :type name: ``str`` + :returns: size and measurement of an LV + :type: ``tuple`` + """ + vg = self._get_lxc_vg() + lv = os.path.join(vg, name) + build_command = [ + 'lvdisplay', + lv + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to read lv %s' % lv, + command=' '.join(build_command) + ) + + lv_info = [i.strip() for i in stdout.splitlines()][1:] + _free_pe = [i for i in lv_info if i.startswith('LV Size')] + free_pe = _free_pe[0].split() + return self._roundup(float(free_pe[-2])), free_pe[-1] + + def _lvm_snapshot_create(self, source_lv, snapshot_name, + snapshot_size_gb=5): + """Create an LVM snapshot. + + :param source_lv: Name of lv to snapshot + :type source_lv: ``str`` + :param snapshot_name: Name of lv snapshot + :type snapshot_name: ``str`` + :param snapshot_size_gb: Size of snapshot to create + :type snapshot_size_gb: ``int`` + """ + vg = self._get_lxc_vg() + free_space, messurement = self._get_vg_free_pe(name=vg) + + if free_space < float(snapshot_size_gb): + message = ( + 'Snapshot size [ %s ] is > greater than [ %s ] on volume group' + ' [ %s ]' % (snapshot_size_gb, free_space, vg) + ) + self.failure( + error='Not enough space to create snapshot', + rc=2, + msg=message + ) + + # Create LVM Snapshot + build_command = [ + self.module.get_bin_path('lvcreate', True), + "-n", + snapshot_name, + "-s", + os.path.join(vg, source_lv), + "-L%sg" % snapshot_size_gb + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='Failed to Create LVM snapshot %s/%s --> %s' + % (vg, source_lv, snapshot_name) + ) + + def _lvm_lv_mount(self, lv_name, mount_point): + """mount an lv. + + :param lv_name: name of the logical volume to mount + :type lv_name: ``str`` + :param mount_point: path on the file system that is mounted. + :type mount_point: ``str`` + """ + vg = self._get_lxc_vg() + + build_command = [ + self.module.get_bin_path('mount', True), + "/dev/%s/%s" % (vg, lv_name), + mount_point, + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to mountlvm lv %s/%s to %s' + % (vg, lv_name, mount_point) + ) + + def _create_tar(self, source_dir): + """Create an archive of a given ``source_dir`` to ``output_path``. + + :param source_dir: Path to the directory to be archived. + :type source_dir: ``str`` + """ + + archive_path = self.module.params.get('archive_path') + if not os.path.isdir(archive_path): + os.makedirs(archive_path) + + archive_compression = self.module.params.get('archive_compression') + compression_type = LXC_COMPRESSION_MAP[archive_compression] + + # remove trailing / if present. + archive_name = '%s.%s' % ( + os.path.join( + archive_path, + self.container_name + ), + compression_type['extension'] + ) + + build_command = [ + self.module.get_bin_path('tar', True), + '--directory=%s' % os.path.realpath( + os.path.expanduser(source_dir) + ), + compression_type['argument'], + archive_name, + '.' + ] + + rc, stdout, err = self._run_command( + build_command=build_command, + unsafe_shell=True + ) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to create tar archive', + command=' '.join(build_command) + ) + + return archive_name + + def _lvm_lv_remove(self, name): + """Remove an LV. + + :param name: The name of the logical volume + :type name: ``str`` + """ + vg = self._get_lxc_vg() + build_command = [ + self.module.get_bin_path('lvremove', True), + "-f", + "%s/%s" % (vg, name), + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='Failed to remove LVM LV %s/%s' % (vg, name), + command=' '.join(build_command) + ) + + def _rsync_data(self, container_path, temp_dir): + """Sync the container directory to the temp directory. + + :param container_path: path to the container container + :type container_path: ``str`` + :param temp_dir: path to the temporary local working directory + :type temp_dir: ``str`` + """ + build_command = [ + self.module.get_bin_path('rsync', True), + '-aHAX', + container_path, + temp_dir + ] + rc, stdout, err = self._run_command(build_command, unsafe_shell=True) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to perform archive', + command=' '.join(build_command) + ) + + def _unmount(self, mount_point): + """Unmount a file system. + + :param mount_point: path on the file system that is mounted. + :type mount_point: ``str`` + """ + build_command = [ + self.module.get_bin_path('umount', True), + mount_point, + ] + rc, stdout, err = self._run_command(build_command) + if rc != 0: + self.failure( + err=err, + rc=rc, + msg='failed to unmount [ %s ]' % mount_point, + command=' '.join(build_command) + ) + + def _container_create_tar(self): + """Create a tar archive from an LXC container. + + The process is as follows: + * Stop or Freeze the container + * Create temporary dir + * Copy container and config to temporary directory + * If LVM backed: + * Create LVM snapshot of LV backing the container + * Mount the snapshot to tmpdir/rootfs + * Restore the state of the container + * Create tar of tmpdir + * Clean up + """ + + # Create a temp dir + temp_dir = tempfile.mkdtemp() + + # Set the name of the working dir, temp + container_name + work_dir = os.path.join(temp_dir, self.container_name) + + # LXC container rootfs + lxc_rootfs = self.container.get_config_item('lxc.rootfs') + + # Test if the containers rootfs is a block device + block_backed = lxc_rootfs.startswith(os.path.join(os.sep, 'dev')) + mount_point = os.path.join(work_dir, 'rootfs') + + # Set the snapshot name if needed + snapshot_name = '%s_lxc_snapshot' % self.container_name + + # Set the path to the container data + container_path = os.path.dirname(lxc_rootfs) + container_state = self._get_state() + try: + # Ensure the original container is stopped or frozen + if container_state not in ['stopped', 'frozen']: + if container_state == 'running': + self.container.freeze() + else: + self.container.stop() + + # Sync the container data from the container_path to work_dir + self._rsync_data(container_path, temp_dir) + + if block_backed: + if snapshot_name not in self._lvm_lv_list(): + if not os.path.exists(mount_point): + os.makedirs(mount_point) + + # Take snapshot + size, measurement = self._get_lv_size( + name=self.container_name + ) + self._lvm_snapshot_create( + source_lv=self.container_name, + snapshot_name=snapshot_name, + snapshot_size_gb=size + ) + + # Mount snapshot + self._lvm_lv_mount( + lv_name=snapshot_name, + mount_point=mount_point + ) + else: + self.failure( + err='snapshot [ %s ] already exists' % snapshot_name, + rc=1, + msg='The snapshot [ %s ] already exists. Please clean' + ' up old snapshot of containers before continuing.' + % snapshot_name + ) + + # Restore original state of container + if container_state == 'running': + if self._get_state() == 'frozen': + self.container.unfreeze() + else: + self.container.start() + + # Set the state as changed and set a new fact + self.state_change = True + return self._create_tar(source_dir=work_dir) + finally: + if block_backed: + # unmount snapshot + self._unmount(mount_point) + + # Remove snapshot + self._lvm_lv_remove(snapshot_name) + + # Remove tmpdir + shutil.rmtree(temp_dir) + + def check_count(self, count, method): + if count > 1: + self.failure( + error='Failed to %s container' % method, + rc=1, + msg='The container [ %s ] failed to %s. Check to lxc is' + ' available and that the container is in a functional' + ' state.' % (self.container_name, method) + ) + + def failure(self, **kwargs): + """Return a Failure when running an Ansible command. + + :param error: ``str`` Error that occurred. + :param rc: ``int`` Return code while executing an Ansible command. + :param msg: ``str`` Message to report. + """ + + self.module.fail_json(**kwargs) + + def run(self): + """Run the main method.""" + + action = getattr(self, LXC_ANSIBLE_STATES[self.state]) + action() + + outcome = self._container_data() + if self.archive_info: + outcome.update(self.archive_info) + + self.module.exit_json( + changed=self.state_change, + lxc_container=outcome + ) + + +def main(): + """Ansible Main module.""" + + module = AnsibleModule( + argument_spec=dict( + name=dict( + type='str', + required=True + ), + template=dict( + type='str', + default='ubuntu' + ), + backing_store=dict( + type='str', + choices=LXC_BACKING_STORE.keys(), + default='dir' + ), + template_options=dict( + type='str' + ), + config=dict( + type='str', + default='/etc/lxc/default.conf' + ), + vg_name=dict( + type='str', + default='lxc' + ), + thinpool=dict( + type='str' + ), + fs_type=dict( + type='str', + default='ext4' + ), + fs_size=dict( + type='str', + default='5G' + ), + directory=dict( + type='str' + ), + zfs_root=dict( + type='str' + ), + lv_name=dict( + type='str' + ), + lxc_path=dict( + type='str' + ), + state=dict( + choices=LXC_ANSIBLE_STATES.keys(), + default='started' + ), + container_command=dict( + type='str' + ), + container_config=dict( + type='str' + ), + container_log=dict( + choices=BOOLEANS, + default='false' + ), + container_log_level=dict( + choices=[n for i in LXC_LOGGING_LEVELS.values() for n in i], + default='INFO' + ), + archive=dict( + choices=BOOLEANS, + default='false' + ), + archive_path=dict( + type='str', + default='/tmp' + ), + archive_compression=dict( + choices=LXC_COMPRESSION_MAP.keys(), + default='gzip' + ) + ), + supports_check_mode=False, + ) + + lv_name = module.params.get('lv_name') + if not lv_name: + module.params['lv_name'] = module.params.get('name') + + lxc_manage = LxcContainerManagement(module=module) + lxc_manage.run() + + +# import module bits +from ansible.module_utils.basic import * +main() + From 99359fc4e216ab85700650e6fff1c86682994390 Mon Sep 17 00:00:00 2001 From: Kevin Carter Date: Tue, 2 Dec 2014 08:18:00 -0600 Subject: [PATCH 2/2] Updated volume create methods for a more consistent process The volume create methods were making an assumption on the unit sizes being presented by the `vgdisplay` and the `lvdisplay` commands. To correct the assumption the commands will now enforce a unit size of "g" which will alway convert sives to gigabytes. This was an issue brought up by @hughsaunders. --- cloud/lxc/lxc-container.py | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/cloud/lxc/lxc-container.py b/cloud/lxc/lxc-container.py index b72890972db..6df27867267 100644 --- a/cloud/lxc/lxc-container.py +++ b/cloud/lxc/lxc-container.py @@ -1015,9 +1015,12 @@ class LxcContainerManagement(object): :returns: size and measurement of an LV :type: ``tuple`` """ + build_command = [ 'vgdisplay', - name + name, + '--units', + 'g' ] rc, stdout, err = self._run_command(build_command) if rc != 0: @@ -1041,11 +1044,14 @@ class LxcContainerManagement(object): :returns: size and measurement of an LV :type: ``tuple`` """ + vg = self._get_lxc_vg() lv = os.path.join(vg, name) build_command = [ 'lvdisplay', - lv + lv, + '--units', + 'g' ] rc, stdout, err = self._run_command(build_command) if rc != 0: @@ -1072,6 +1078,7 @@ class LxcContainerManagement(object): :param snapshot_size_gb: Size of snapshot to create :type snapshot_size_gb: ``int`` """ + vg = self._get_lxc_vg() free_space, messurement = self._get_vg_free_pe(name=vg) @@ -1112,6 +1119,7 @@ class LxcContainerManagement(object): :param mount_point: path on the file system that is mounted. :type mount_point: ``str`` """ + vg = self._get_lxc_vg() build_command = [ @@ -1181,6 +1189,7 @@ class LxcContainerManagement(object): :param name: The name of the logical volume :type name: ``str`` """ + vg = self._get_lxc_vg() build_command = [ self.module.get_bin_path('lvremove', True), @@ -1204,6 +1213,7 @@ class LxcContainerManagement(object): :param temp_dir: path to the temporary local working directory :type temp_dir: ``str`` """ + build_command = [ self.module.get_bin_path('rsync', True), '-aHAX', @@ -1225,6 +1235,7 @@ class LxcContainerManagement(object): :param mount_point: path on the file system that is mounted. :type mount_point: ``str`` """ + build_command = [ self.module.get_bin_path('umount', True), mount_point,