Don't instantiate tasks

In practice they are just typed functions with attributes, having a reference to an object is just confusing.
So: Task.run() is now a classmethod

base/task.py

@@ -5,8 +5,13 @@ class Task(object):
 	predecessors = []
 	successors = []
 
-	def __str__(self):
-		return '{module}.{task}'.format(module=self.__module__, task=self.__class__.__name__)
+	class __metaclass__(type):
+		def __repr__(cls):
+			return '{module}.{task}'.format(module=cls.__module__, task=cls.__name__)
 
-	def __repr__(self):
-		return self.__str__()
+		def __str__(cls):
+			return repr(cls)
+
+	@classmethod
+	def run(cls, info):
+		pass

base/tasklist.py

@@ -18,17 +18,16 @@ class TaskList(object):
 
 	def run(self, info={}, dry_run=False):
 		task_list = self.create_list()
-		log.debug('Tasklist:\n\t{list}'.format(list='\n\t'.join(repr(task) for task in task_list)))
+		log.debug('Tasklist:\n\t{list}'.format(list='\n\t'.join(map(repr, task_list))))
 
-		for task_type in task_list:
-			task = task_type()
+		for task in task_list:
 			if hasattr(task, 'description'):
 				log.info(task.description)
 			else:
 				log.info('Running {task}'.format(task=task))
 			if not dry_run:
 				task.run(info)
-			self.tasks_completed.append(task_type)
+			self.tasks_completed.append(task)
 
 	def create_list(self):
 		from common.phases import order
@@ -47,7 +46,7 @@ class TaskList(object):
 		for component in components:
 			if len(component) > 1:
 				cycles_found += 1
-				log.debug('Cycle: {list}\n'.format(list=', '.join(repr(task) for task in component)))
+				log.debug('Cycle: {list}\n'.format(list=', '.join(map(repr, component))))
 		if cycles_found > 0:
 			msg = ('{0} cycles were found in the tasklist, '
 			       'consult the logfile for more information.'.format(cycles_found))

common/tasks/apt.py

@@ -9,7 +9,8 @@ class AddDefaultSources(Task):
 	description = 'Adding default release sources'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if info.source_lists.target_exists('{system.release}'):
 			import logging
 			msg = ('{system.release} target already exists').format(**info.manifest_vars)
@@ -25,7 +26,8 @@ class WriteSources(Task):
 	description = 'Writing aptitude sources to disk'
 	phase = phases.package_installation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		for name, sources in info.source_lists.sources.iteritems():
 			if name == 'main':
 				list_path = os.path.join(info.root, 'etc/apt/sources.list')
@@ -40,7 +42,8 @@ class DisableDaemonAutostart(Task):
 	description = 'Disabling daemon autostart'
 	phase = phases.package_installation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		rc_policy_path = os.path.join(info.root, 'usr/sbin/policy-rc.d')
 		with open(rc_policy_path, 'w') as rc_policy:
 			rc_policy.write(('#!/bin/sh\n'
@@ -57,7 +60,8 @@ class AptUpdate(Task):
 	phase = phases.package_installation
 	predecessors = [locale.GenerateLocale, WriteSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		log_check_call(['/usr/sbin/chroot', info.root,
 		                '/usr/bin/apt-get', 'update'])
 
@@ -67,7 +71,8 @@ class AptUpgrade(Task):
 	phase = phases.package_installation
 	predecessors = [AptUpdate, DisableDaemonAutostart]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from subprocess import CalledProcessError
 		try:
 			log_check_call(['/usr/sbin/chroot', info.root,
@@ -93,7 +98,8 @@ class PurgeUnusedPackages(Task):
 	description = 'Removing unused packages'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		log_check_call(['/usr/sbin/chroot', info.root,
 		                '/usr/bin/apt-get', 'autoremove',
 		                                    '--purge'])
@@ -103,7 +109,8 @@ class AptClean(Task):
 	description = 'Clearing the aptitude cache'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		log_check_call(['/usr/sbin/chroot', info.root,
 		                '/usr/bin/apt-get', 'clean'])
 
@@ -117,5 +124,6 @@ class EnableDaemonAutostart(Task):
 	description = 'Re-enabling daemon autostart after installation'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		os.remove(os.path.join(info.root, 'usr/sbin/policy-rc.d'))

common/tasks/boot.py

@@ -8,7 +8,8 @@ class BlackListModules(Task):
 	description = 'Blacklisting kernel modules'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		blacklist_path = os.path.join(info.root, 'etc/modprobe.d/blacklist.conf')
 		with open(blacklist_path, 'a') as blacklist:
 			blacklist.write(('# disable pc speaker\n'
@@ -19,7 +20,8 @@ class DisableGetTTYs(Task):
 	description = 'Disabling getty processes'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import sed_i
 		inittab_path = os.path.join(info.root, 'etc/inittab')
 		tty1 = '1:2345:respawn:/sbin/getty 38400 tty1'
@@ -35,7 +37,8 @@ class AddGrubPackage(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('grub-pc')
 
 
@@ -44,7 +47,8 @@ class InstallGrub(Task):
 	phase = phases.system_modification
 	predecessors = [apt.AptUpgrade]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.fs.loopbackvolume import LoopbackVolume
 		from common.tools import log_check_call
 
@@ -107,7 +111,8 @@ class AddExtlinuxPackage(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('extlinux')
 
 
@@ -116,7 +121,8 @@ class InstallExtLinux(Task):
 	phase = phases.system_modification
 	predecessors = [apt.AptUpgrade]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 		log_check_call(['/usr/sbin/chroot', info.root,
 		                '/usr/bin/extlinux',

common/tasks/bootstrap.py

@@ -21,7 +21,8 @@ class MakeTarball(Task):
 	description = 'Creating bootstrap tarball'
 	phase = phases.os_installation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from hashlib import sha1
 		import os.path
 		executable, options, arguments = get_bootstrap_args(info)
@@ -45,7 +46,8 @@ class Bootstrap(Task):
 	phase = phases.os_installation
 	predecessors = [MakeTarball]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		executable, options, arguments = get_bootstrap_args(info)
 		if hasattr(info, 'tarball'):
 			options.extend(['--unpack-tarball=' + info.tarball])

common/tasks/cleanup.py

@@ -8,7 +8,8 @@ class ClearMOTD(Task):
 	description = 'Clearing the MOTD'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		with open('/var/run/motd', 'w'):
 			pass
 
@@ -17,7 +18,8 @@ class ShredHostkeys(Task):
 	description = 'Securely deleting ssh hostkeys'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		ssh_hostkeys = ['ssh_host_dsa_key',
 		                'ssh_host_rsa_key']
 		if info.manifest.system['release'] != 'squeeze':
@@ -34,7 +36,8 @@ class CleanTMP(Task):
 	description = 'Removing temporary files'
 	phase = phases.system_cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		tmp = os.path.join(info.root, 'tmp')
 		for tmp_file in [os.path.join(tmp, f) for f in os.listdir(tmp)]:
 			if os.path.isfile(tmp_file):

common/tasks/development.py

@@ -7,6 +7,7 @@ class TriggerRollback(Task):
 
 	description = 'Triggering a rollback by throwing an exception'
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.exceptions import TaskError
 		raise TaskError('Trigger rollback')

common/tasks/filesystem.py

@@ -10,7 +10,8 @@ class Format(Task):
 	description = 'Formatting the volume'
 	phase = phases.volume_preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		for partition in info.volume.partition_map.partitions:
 			partition.format()
 
@@ -20,7 +21,8 @@ class TuneVolumeFS(Task):
 	phase = phases.volume_preparation
 	predecessors = [Format]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import re
 		# Disable the time based filesystem check
 		for partition in info.volume.partition_map.partitions:
@@ -33,7 +35,8 @@ class AddXFSProgs(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('xfsprogs')
 
 
@@ -41,7 +44,8 @@ class CreateMountDir(Task):
 	description = 'Creating mountpoint for the root partition'
 	phase = phases.volume_mounting
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os
 		info.root = os.path.join(info.workspace, 'root')
 		os.makedirs(info.root)
@@ -52,7 +56,8 @@ class MountRoot(Task):
 	phase = phases.volume_mounting
 	predecessors = [CreateMountDir]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.partition_map.root.mount(info.root)
 
 
@@ -61,7 +66,8 @@ class CreateBootMountDir(Task):
 	phase = phases.volume_mounting
 	predecessors = [MountRoot]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		os.makedirs(os.path.join(info.root, 'boot'))
 
@@ -71,7 +77,8 @@ class MountBoot(Task):
 	phase = phases.volume_mounting
 	predecessors = [CreateBootMountDir]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		p_map = info.volume.partition_map
 		p_map.root.add_mount(p_map.boot, 'boot')
 
@@ -81,7 +88,8 @@ class MountSpecials(Task):
 	phase = phases.os_installation
 	predecessors = [Bootstrap]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		root = info.volume.partition_map.root
 		root.add_mount('/dev', 'dev', ['--bind'])
 		root.add_mount('none', 'proc', ['--types', 'proc'])
@@ -94,7 +102,8 @@ class UnmountRoot(Task):
 	phase = phases.volume_unmounting
 	successors = [volume.Detach]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.partition_map.root.unmount()
 
 
@@ -103,7 +112,8 @@ class DeleteMountDir(Task):
 	phase = phases.volume_unmounting
 	predecessors = [UnmountRoot]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os
 		os.rmdir(info.root)
 		del info.root
@@ -113,7 +123,8 @@ class FStab(Task):
 	description = 'Adding partitions to the fstab'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		p_map = info.volume.partition_map
 		mount_points = [{'path': '/',

common/tasks/host.py

@@ -7,7 +7,8 @@ class HostDependencies(Task):
 	description = 'Determining required host dependencies'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.host_dependencies.add('debootstrap')
 
 		from common.fs.loopbackvolume import LoopbackVolume
@@ -27,7 +28,8 @@ class CheckHostDependencies(Task):
 	phase = phases.preparation
 	predecessors = [HostDependencies]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 		from subprocess import CalledProcessError
 		for package in info.host_dependencies:

common/tasks/initd.py

@@ -10,7 +10,8 @@ class InstallInitScripts(Task):
 	description = 'Installing startup scripts'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import stat
 		rwxr_xr_x = (stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR |
 		             stat.S_IRGRP                | stat.S_IXGRP |
@@ -31,7 +32,8 @@ class AddExpandRoot(Task):
 	phase = phases.system_modification
 	successors = [InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		init_scripts_dir = os.path.join(assets, 'init.d')
 		info.initd['install']['expand-root'] = os.path.join(init_scripts_dir, 'expand-root')
 
@@ -41,7 +43,8 @@ class AddSSHKeyGeneration(Task):
 	phase = phases.system_modification
 	successors = [InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		init_scripts_dir = os.path.join(assets, 'init.d')
 		install = info.initd['install']
 		from subprocess import CalledProcessError
@@ -63,7 +66,8 @@ class RemoveHWClock(Task):
 	phase = phases.system_modification
 	successors = [InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.initd['disable'].append('hwclock.sh')
 		if info.manifest.system['release'] == 'squeeze':
 			info.initd['disable'].append('hwclockfirst.sh')
@@ -74,7 +78,8 @@ class AdjustExpandRootScript(Task):
 	phase = phases.system_modification
 	predecessors = [InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if 'expand-root' not in info.initd['install']:
 			raise TaskError('The expand-root script was not installed')
 

common/tasks/locale.py

@@ -7,7 +7,8 @@ class LocaleBootstrapPackage(Task):
 	description = 'Adding locale package to bootstrap installation'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		# We could bootstrap without locales, but things just suck without them
 		# eg. error messages when running apt
 		info.include_packages.add('locales')
@@ -17,7 +18,8 @@ class GenerateLocale(Task):
 	description = 'Generating the selected locale'
 	phase = phases.package_installation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import sed_i
 		from common.tools import log_check_call
 		locale_gen = os.path.join(info.root, 'etc/locale.gen')
@@ -38,7 +40,8 @@ class SetTimezone(Task):
 	description = 'Setting the selected timezone'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from shutil import copy
 		tz_path = os.path.join(info.root, 'etc/timezone')
 		timezone = info.manifest.system['timezone']

common/tasks/loopback.py

@@ -8,7 +8,8 @@ class Create(Task):
 	phase = phases.volume_creation
 	successors = [volume.Attach]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		image_path = os.path.join(info.workspace, 'volume.{ext}'.format(ext=info.volume.extension))
 		info.volume.create(image_path)
@@ -18,7 +19,8 @@ class MoveImage(Task):
 	description = 'Moving volume image'
 	phase = phases.image_registration
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		image_name = info.manifest.image['name'].format(**info.manifest_vars)
 		filename = '{image_name}.{ext}'.format(image_name=image_name, ext=info.volume.extension)
 

common/tasks/network.py

@@ -7,7 +7,8 @@ class RemoveDNSInfo(Task):
 	description = 'Removing resolv.conf'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from os import remove
 		remove(os.path.join(info.root, 'etc/resolv.conf'))
 
@@ -16,7 +17,8 @@ class RemoveHostname(Task):
 	description = 'Removing the hostname file'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from os import remove
 		remove(os.path.join(info.root, 'etc/hostname'))
 
@@ -25,7 +27,8 @@ class ConfigureNetworkIF(Task):
 	description = 'Configuring network interfaces'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		interfaces_path = os.path.join(info.root, 'etc/network/interfaces')
 		if_config = {'squeeze': ('auto lo\n'
 		                         'iface lo inet loopback\n'

common/tasks/packages.py

@@ -8,7 +8,8 @@ class InstallRemotePackages(Task):
 	phase = phases.package_installation
 	predecessors = [apt.AptUpgrade]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if len(info.packages.remote) == 0:
 			return
 		import os
@@ -59,7 +60,8 @@ class InstallLocalPackages(Task):
 	predecessors = [apt.AptUpgrade]
 	successors = [InstallRemotePackages]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if len(info.packages.local) == 0:
 			return
 		from shutil import copy

common/tasks/partitioning.py

@@ -8,7 +8,8 @@ class PartitionVolume(Task):
 	description = 'Partitioning the volume'
 	phase = phases.volume_preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.partition_map.create(info.volume)
 
 
@@ -18,7 +19,8 @@ class MapPartitions(Task):
 	predecessors = [PartitionVolume]
 	successors = [filesystem.Format]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.partition_map.map(info.volume)
 
 
@@ -28,5 +30,6 @@ class UnmapPartitions(Task):
 	predecessors = [filesystem.UnmountRoot]
 	successors = [volume.Detach]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.partition_map.unmap(info.volume)

common/tasks/security.py

@@ -7,7 +7,8 @@ class EnableShadowConfig(Task):
 	description = 'Enabling shadowconfig'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 		log_check_call(['/usr/sbin/chroot', info.root, '/sbin/shadowconfig', 'on'])
 
@@ -16,7 +17,8 @@ class DisableSSHPasswordAuthentication(Task):
 	description = 'Disabling SSH password authentication'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import sed_i
 		sshd_config_path = os.path.join(info.root, 'etc/ssh/sshd_config')
 		sed_i(sshd_config_path, '^#PasswordAuthentication yes', 'PasswordAuthentication no')
@@ -26,7 +28,8 @@ class DisableSSHDNSLookup(Task):
 	description = 'Disabling sshd remote host name lookup'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		sshd_config_path = os.path.join(info.root, 'etc/ssh/sshd_config')
 		with open(sshd_config_path, 'a') as sshd_config:
 			sshd_config.write('UseDNS no')

common/tasks/volume.py

@@ -7,7 +7,8 @@ class Attach(Task):
 	description = 'Attaching the volume'
 	phase = phases.volume_creation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.attach()
 
 
@@ -15,7 +16,8 @@ class Detach(Task):
 	description = 'Detaching the volume'
 	phase = phases.volume_unmounting
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.detach()
 
 
@@ -24,5 +26,6 @@ class Delete(Task):
 	phase = phases.cleaning
 	successors = [workspace.DeleteWorkspace]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.delete()

common/tasks/workspace.py

@@ -6,7 +6,8 @@ class CreateWorkspace(Task):
 	description = 'Creating workspace'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os
 		os.makedirs(info.workspace)
 
@@ -15,6 +16,7 @@ class DeleteWorkspace(Task):
 	description = 'Deleting workspace'
 	phase = phases.cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os
 		os.rmdir(info.workspace)

plugins/admin_user/tasks.py

@@ -10,7 +10,8 @@ class AddSudoPackage(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('sudo')
 
 
@@ -18,7 +19,8 @@ class CreateAdminUser(Task):
 	description = 'Creating the admin user'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 		log_check_call(['/usr/sbin/chroot', info.root,
 		                '/usr/sbin/useradd',
@@ -30,7 +32,8 @@ class PasswordlessSudo(Task):
 	description = 'Allowing the admin user to use sudo without a password'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		sudo_admin_path = os.path.join(info.root, 'etc/sudoers.d/99_admin')
 		username = info.manifest.plugins['admin_user']['username']
 		with open(sudo_admin_path, 'w') as sudo_admin:
@@ -45,7 +48,8 @@ class AdminUserCredentials(Task):
 	phase = phases.system_modification
 	predecessors = [InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import sed_i
 		getcreds_path = os.path.join(info.root, 'etc/init.d/ec2-get-credentials')
 		username = info.manifest.plugins['admin_user']['username']
@@ -56,7 +60,8 @@ class DisableRootLogin(Task):
 	description = 'Disabling SSH login for root'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from subprocess import CalledProcessError
 		from common.tools import log_check_call
 		try:

plugins/build_metadata/tasks.py

@@ -6,7 +6,8 @@ class WriteMetadata(Task):
 	description = 'Writing bootstrap metadata to file'
 	phase = phases.cleaning
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		metadata_path = info.manifest.plugins['build_metadata']['path']
 		with open(metadata_path, 'w') as metadata:
 			metadata.write(('AMI_ID={ami_id}\n'

plugins/cloud_init/tasks.py

@@ -9,7 +9,8 @@ class AddBackports(Task):
 	description = 'Adding backports to the apt sources'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if info.source_lists.target_exists('{system.release}-backports'):
 			import logging
 			msg = ('{system.release}-backports target already exists').format(**info.manifest_vars)
@@ -24,7 +25,8 @@ class AddCloudInitPackages(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources, AddBackports]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		target = None
 		if info.manifest.system['release'] in ['wheezy', 'stable']:
 			target = '{system.release}-backports'
@@ -36,7 +38,8 @@ class SetUsername(Task):
 	description = 'Setting username in cloud.cfg'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import sed_i
 		cloud_cfg = os.path.join(info.root, 'etc/cloud/cloud.cfg')
 		username = info.manifest.plugins['cloud_init']['username']
@@ -51,7 +54,8 @@ class SetMetadataSource(Task):
 	description = 'Setting metadata source'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if 'metadata_sources' in info.manifest.plugins['cloud_init']:
 			sources = info.manifest.plugins['cloud_init']['metadata_sources']
 		else:
@@ -71,7 +75,8 @@ class DisableModules(Task):
 	description = 'Setting cloud.cfg modules'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import re
 		patterns = ""
 		for pattern in info.manifest.plugins['cloud_init']['disable_modules']:

plugins/image_commands/tasks.py

@@ -6,7 +6,8 @@ class ImageExecuteCommand(Task):
 	description = 'Execute command in the image'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 
 		for user_cmd in info.manifest.plugins['image_commands']['commands']:

plugins/minimize_size/tasks.py

@@ -12,7 +12,8 @@ class AddFolderMounts(Task):
 	phase = phases.os_installation
 	predecessors = [bootstrap.Bootstrap]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.minimize_size_folder = os.path.join(info.workspace, 'minimize_size')
 		os.mkdir(info.minimize_size_folder)
 		for folder in folders:
@@ -28,7 +29,8 @@ class RemoveFolderMounts(Task):
 	phase = phases.system_cleaning
 	successors = [apt.AptClean]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import shutil
 		for folder in folders:
 			temp_path = os.path.join(info.minimize_size_folder, folder.replace('/', '_'))

plugins/opennebula/tasks.py

@@ -11,7 +11,8 @@ class OpenNebulaContext(Task):
 	phase = phases.system_modification
 	predecessors = [GenerateLocale]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import stat
 		rwxr_xr_x = (stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR |
 		             stat.S_IRGRP                | stat.S_IXGRP |

plugins/prebootstrapped/tasks.py

@@ -17,7 +17,8 @@ class Snapshot(Task):
 	phase = phases.package_installation
 	predecessors = [packages.InstallRemotePackages, guest_additions.InstallGuestAdditions]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		def mk_snapshot():
 			return info.volume.snapshot()
 		snapshot = remount(info.volume, mk_snapshot)
@@ -30,7 +31,8 @@ class CreateFromSnapshot(Task):
 	phase = phases.volume_creation
 	successors = [ebs.Attach]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		volume_size = int(info.volume.partition_map.get_total_size() / 1024)
 		snapshot = info.manifest.plugins['prebootstrapped']['snapshot']
 		ebs_volume = info.connection.create_volume(volume_size,
@@ -49,7 +51,8 @@ class CopyImage(Task):
 	phase = phases.package_installation
 	predecessors = [packages.InstallRemotePackages, guest_additions.InstallGuestAdditions]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		loopback_backup_name = 'volume-{id}.{ext}.backup'.format(id=info.run_id, ext=info.volume.extension)
 		destination = os.path.join(info.manifest.bootstrapper['workspace'], loopback_backup_name)
 
@@ -65,7 +68,8 @@ class CreateFromImage(Task):
 	phase = phases.volume_creation
 	successors = [volume.Attach]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.image_path = os.path.join(info.workspace, 'volume.{ext}'.format(ext=info.volume.extension))
 		loopback_backup_path = info.manifest.plugins['prebootstrapped']['image']
 		copyfile(loopback_backup_path, info.volume.image_path)

plugins/root_password/tasks.py

@@ -6,7 +6,8 @@ class SetRootPassword(Task):
 	description = 'Setting the root password'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from common.tools import log_check_call
 		log_check_call(['/usr/sbin/chroot', info.root, '/usr/sbin/chpasswd'],
 		               'root:' + info.manifest.plugins['root_password']['password'])

plugins/unattended_upgrades/tasks.py

@@ -8,7 +8,8 @@ class AddUnattendedUpgradesPackage(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('unattended-upgrades')
 
 
@@ -16,7 +17,8 @@ class EnablePeriodicUpgrades(Task):
 	description = 'Writing the periodic upgrades apt config file'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		periodic_path = os.path.join(info.root, 'etc/apt/apt.conf.d/02periodic')
 		update_interval = info.manifest.plugins['unattended_upgrades']['update_interval']

plugins/vagrant/tasks.py

@@ -14,7 +14,8 @@ class CreateVagrantBoxDir(Task):
 	phase = phases.preparation
 	predecessors = [workspace.CreateWorkspace]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.vagrant_folder = os.path.join(info.workspace, 'vagrant')
 		os.mkdir(info.vagrant_folder)
 
@@ -24,7 +25,8 @@ class AddPackages(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('openssh-server')
 
 
@@ -33,7 +35,8 @@ class AddInsecurePublicKey(Task):
 	phase = phases.system_modification
 	predecessors = [CreateAdminUser]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		ssh_dir = os.path.join(info.root, 'home/vagrant/.ssh')
 		os.mkdir(ssh_dir)
 
@@ -50,7 +53,8 @@ class PackageBox(Task):
 	description = 'Packaging the volume as a vagrant box'
 	phase = phases.image_registration
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		box_basename = info.manifest.image['name'].format(**info.manifest_vars)
 		box_name = '{name}.box'.format(name=box_basename)
 		box_path = os.path.join(info.manifest.bootstrapper['workspace'], box_name)
@@ -74,7 +78,7 @@ class PackageBox(Task):
 		log_check_call(['ln', '-s', info.volume.image_path, disk_link])
 
 		ovf_path = os.path.join(info.vagrant_folder, 'box.ovf')
-		self.write_ovf(info, ovf_path, box_name, mac_address, disk_name)
+		cls.write_ovf(info, ovf_path, box_name, mac_address, disk_name)
 
 		box_files = os.listdir(info.vagrant_folder)
 		log_check_call(['tar', '--create', '--gzip', '--dereference',
@@ -86,7 +90,7 @@ class PackageBox(Task):
 		logging.getLogger(__name__).info('The vagrant box has been placed at {box_path}'
 		                                 .format(box_path=box_path))
 
-	def write_ovf(self, info, destination, box_name, mac_address, disk_name):
+	def write_ovf(info, destination, box_name, mac_address, disk_name):
 		namespaces = {'ovf':     'http://schemas.dmtf.org/ovf/envelope/1',
 		              'rasd':    'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData',
 		              'vssd':    'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_VirtualSystemSettingData',
@@ -153,6 +157,7 @@ class RemoveVagrantBoxDir(Task):
 	phase = phases.cleaning
 	successors = [workspace.DeleteWorkspace]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		shutil.rmtree(info.vagrant_folder)
 		del info.vagrant_folder

providers/ec2/tasks/ami.py

@@ -16,7 +16,8 @@ class AMIName(Task):
 	phase = phases.preparation
 	predecessors = [Connect]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		ami_name = info.manifest.image['name'].format(**info.manifest_vars)
 		ami_description = info.manifest.image['description'].format(**info.manifest_vars)
 
@@ -33,7 +34,8 @@ class BundleImage(Task):
 	description = 'Bundling the image'
 	phase = phases.image_registration
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		bundle_name = 'bundle-{id}'.format(id=info.run_id)
 		info.bundle_path = os.path.join(info.workspace, bundle_name)
 		log_check_call(['/usr/bin/euca-bundle-image',
@@ -51,7 +53,8 @@ class UploadImage(Task):
 	phase = phases.image_registration
 	predecessors = [BundleImage]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		manifest_file = os.path.join(info.bundle_path, info.ami_name + '.manifest.xml')
 		if info.host['region'] == 'us-east-1':
 			s3_url = 'https://s3.amazonaws.com/'
@@ -72,7 +75,8 @@ class RemoveBundle(Task):
 	phase = phases.cleaning
 	successors = [workspace.DeleteWorkspace]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from shutil import rmtree
 		rmtree(info.bundle_path)
 		del info.bundle_path
@@ -140,7 +144,8 @@ class RegisterAMI(Task):
 	                   }
 	                  }
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		registration_params = {'name': info.ami_name,
 		                       'description': info.ami_description}
 		registration_params['architecture'] = {'i386': 'i386',
@@ -169,7 +174,7 @@ class RegisterAMI(Task):
 			registration_params['virtualization_type'] = 'hvm'
 		else:
 			registration_params['virtualization_type'] = 'paravirtual'
-			registration_params['kernel_id'] = (self.kernel_mapping
+			registration_params['kernel_id'] = (cls.kernel_mapping
 			                                    .get(info.host['region'])
 			                                    .get(grub_boot_device)
 			                                    .get(info.manifest.system['architecture']))

providers/ec2/tasks/boot.py

@@ -8,7 +8,8 @@ class ConfigurePVGrub(Task):
 	description = 'Creating grub config files for PVGrub'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import stat
 		rwxr_xr_x = (stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR |
 		             stat.S_IRGRP                | stat.S_IXGRP |

providers/ec2/tasks/connection.py

@@ -7,13 +7,15 @@ class GetCredentials(Task):
 	description = 'Getting AWS credentials'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		keys = ['access-key', 'secret-key']
 		if info.manifest.volume['backing'] == 's3':
 			keys.extend(['certificate', 'private-key', 'user-id'])
-		info.credentials = self.get_credentials(info.manifest, keys)
+		info.credentials = cls.get_credentials(info.manifest, keys)
 
-	def get_credentials(self, manifest, keys):
+	@classmethod
+	def get_credentials(cls, manifest, keys):
 		from os import getenv
 		creds = {}
 		if all(key in manifest.data['credentials'] for key in keys):
@@ -36,7 +38,8 @@ class Connect(Task):
 	phase = phases.preparation
 	predecessors = [GetCredentials, host.GetInfo]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		from boto.ec2 import connect_to_region
 		info.connection = connect_to_region(info.host['region'],
 		                                    aws_access_key_id=info.credentials['access-key'],

providers/ec2/tasks/ebs.py

@@ -6,7 +6,8 @@ class Create(Task):
 	description = 'Creating the EBS volume'
 	phase = phases.volume_creation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.create(info.connection, info.host['availabilityZone'])
 
 
@@ -15,7 +16,8 @@ class Attach(Task):
 	phase = phases.volume_creation
 	predecessors = [Create]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.volume.attach(info.host['instanceId'])
 
 
@@ -23,5 +25,6 @@ class Snapshot(Task):
 	description = 'Creating a snapshot of the EBS volume'
 	phase = phases.image_registration
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.snapshot = info.volume.snapshot()

providers/ec2/tasks/filesystem.py

@@ -6,7 +6,8 @@ class S3FStab(Task):
 	description = 'Adding the S3 root partition to the fstab'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		root = info.volume.partition_map.root
 

providers/ec2/tasks/host.py

@@ -8,7 +8,8 @@ class HostDependencies(Task):
 	phase = phases.preparation
 	successors = [host.CheckHostDependencies]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		if info.manifest.volume['backing'] == 's3':
 			info.host_dependencies.add('euca2ools')
 
@@ -17,7 +18,8 @@ class GetInfo(Task):
 	description = 'Retrieving instance metadata'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import urllib2
 		import json
 		metadata_url = 'http://169.254.169.254/latest/dynamic/instance-identity/document'

providers/ec2/tasks/initd.py

@@ -10,7 +10,8 @@ class AddEC2InitScripts(Task):
 	phase = phases.system_modification
 	successors = [initd.InstallInitScripts]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		init_scripts = {'ec2-get-credentials': 'ec2-get-credentials',
 		                'ec2-run-user-data': 'ec2-run-user-data'}
 

providers/ec2/tasks/network.py

@@ -8,7 +8,8 @@ class EnableDHCPCDDNS(Task):
 	description = 'Configuring the DHCP client to set the nameservers'
 	phase = phases.system_modification
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		# The dhcp client that ships with debian sets the DNS servers per default.
 		# For dhcpcd we need to configure it to do that.
 		from common.tools import sed_i
@@ -21,7 +22,8 @@ class AddBuildEssentialPackage(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('build-essential')
 
 
@@ -29,7 +31,8 @@ class InstallEnhancedNetworking(Task):
 	description = 'Installing network drivers for SR-IOV support'
 	phase = phases.package_installation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		drivers_url = 'http://downloads.sourceforge.net/project/e1000/ixgbevf stable/2.11.3/ixgbevf-2.11.3.tar.gz'
 		archive = os.path.join(info.root, 'tmp', 'ixgbevf-2.11.3.tar.gz')
 

providers/ec2/tasks/packages.py

@@ -8,7 +8,8 @@ class DefaultPackages(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('openssh-server')
 		info.packages.add('file')  # Needed for the init scripts
 		info.packages.add('dhcpcd')  # isc-dhcp-client doesn't work properly with ec2

providers/virtualbox/tasks/guest_additions.py

@@ -8,7 +8,8 @@ class CheckGuestAdditionsPath(Task):
 	description = 'Checking whether the VirtualBox Guest Additions image exists'
 	phase = phases.preparation
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os.path
 		guest_additions_path = info.manifest.bootstrapper['guest_additions']
 		if not os.path.exists(guest_additions_path):
@@ -21,7 +22,8 @@ class AddGuestAdditionsPackages(Task):
 	phase = phases.package_installation
 	successors = [InstallRemotePackages]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		info.packages.add('bzip2')
 		info.packages.add('build-essential')
 		info.packages.add('dkms')
@@ -38,7 +40,8 @@ class InstallGuestAdditions(Task):
 	phase = phases.package_installation
 	predecessors = [InstallRemotePackages]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		import os
 		guest_additions_path = info.manifest.bootstrapper['guest_additions']
 		mount_dir = 'mnt/guest_additions'

providers/virtualbox/tasks/packages.py

@@ -8,7 +8,8 @@ class DefaultPackages(Task):
 	phase = phases.preparation
 	predecessors = [apt.AddDefaultSources]
 
-	def run(self, info):
+	@classmethod
+	def run(cls, info):
 		kernels = {'amd64': 'linux-image-amd64',
 		           'i386':  'linux-image-686', }
 		info.packages.add(kernels.get(info.manifest.system['architecture']))