lago package¶
Subpackages¶
Submodules¶
lago.brctl module¶
lago.build module¶
-
class
lago.build.
Build
(name, disk_path, paths)[source]¶ Bases:
object
A Build object represents a build section in the init file. Each build section (which in turn belongs to a specific disk) should get his own Build object
In order to add support for a new build command, a new function with the name of the command should be implemented in this class. this function should accept a list of options and arguments and return a named tuple ‘Command’, where ‘Command.name’ is the name of the command and ‘Command.cmd’ is the a list containing the command and its args, for example: Command.name = ‘virt-customize’ Command.cmd = [‘virt-customize’, ‘-a’, PATH_TO_DISK, SOME_CMDS...]
-
name
¶ str – The name of the vm this builder belongs
-
disk_path
¶ str – The path to the disk that needs to be customized
-
paths
¶ lago.paths.Paths – The paths of the current prefix
-
build_cmds
¶ list of str – A list of commands that should be invoked on the disk located in disk_path
-
build
()[source]¶ Run all the commands in self.build_cmds
Raises: lago.build.BuildException
– If a command returned a non-zero code
-
get_cmd_handler
(cmd)[source]¶ Return an handler for cmd. The handler and the command should have the same name. See class description for more info about handlers.
Parameters: cmd (str) – The name of the command Returns: which handles cmd Return type: callable Raises: lago.build.BuildException
– If an handler for cmd doesn’t exist
-
classmethod
get_instance_from_build_spec
(name, disk_path, build_spec, paths)[source]¶ Parameters: - name (str) – The name of the vm this builder belongs
- disk_path (str) – The path to the disk that needs to be customized
- paths (lago.paths.Paths) – The paths of the current prefix
- build_spec (dict) – The build spec part, associated with the disk located at disk_path, from the init file.
Returns: - An instance of Build with a normalized build spec i.e ready to
be invoked.
-
normalize_build_spec
(build_spec)[source]¶ Convert a build spec into a list of Command tuples. After running this command, self.build_cmds should hold all the commands that should be run on the disk in self.disk_path.
Parameters: build_spec (dict) – The buildspec part from the init file
-
static
normalize_options
(options)[source]¶ Turns a mapping of ‘option: arg’ to a list and prefix the options. arg can be a list of arguments.
for example:
- dict = {
- o1: a1, o2: , o3: [a31, a32] o4: []
}
will be transformed to:
- [
- prefix_option(o1), a1, prefix_option(o2), prefix_option(o3), a31, prefix_option(o3), a32 prefix_option(o4)
]
note that empty arguments are omitted
Parameters: options (dict) – A mapping between options and arguments Returns: A normalized version of ‘options’ as mentioned above Return type: lst
-
static
prefix_option
(option)[source]¶ Depends on the option’s length, prefix it with ‘-‘ or ‘–’ :param option: The option to prefix :type option: str
Returns: prefixed option Return type: str
-
virt_customize
(options)[source]¶ Handler for ‘virt-customize’ note: if ‘ssh-inject’ option was specified without a path to a key, the prefix’ key will be copied to the vm.
Parameters: options (lst of str) – Options and arguments for ‘virt-customize’ Returns: which handles cmd Return type: callable Raises: lago.build.BuildException
– If an handler for cmd doesn’t exist
-
-
exception
lago.build.
BuildException
[source]¶ Bases:
lago.utils.LagoException
-
class
lago.build.
Command
(name, cmd)¶ Bases:
tuple
-
__getnewargs__
()¶ Return self as a plain tuple. Used by copy and pickle.
-
__getstate__
()¶ Exclude the OrderedDict from pickling
-
__repr__
()¶ Return a nicely formatted representation string
-
_asdict
()¶ Return a new OrderedDict which maps field names to their values
-
_fields
= ('name', 'cmd')¶
-
classmethod
_make
(iterable, new=<built-in method __new__ of type object at 0x906d60>, len=<built-in function len>)¶ Make a new Command object from a sequence or iterable
-
_replace
(_self, **kwds)¶ Return a new Command object replacing specified fields with new values
-
cmd
¶ Alias for field number 1
-
name
¶ Alias for field number 0
-
lago.cmd module¶
lago.config module¶
-
class
lago.config.
ConfigLoad
(root_section='lago', defaults={})[source]¶ Bases:
object
Merges configuration parameters from 3 different sources: 1. Enviornment vairables 2. config files in .INI format 3. argparse.ArgumentParser
The assumed order(but not necessary) order of calls is: load() - load from config files and environment variables update_parser(parser) - update from the declared argparse parser update_args(args) - update from passed arguments to the parser
-
__getitem__
(key)[source]¶ Get a variable from the default section, good for fail-fast if key does not exists.
Parameters: key (str) – key Returns: config variable Return type: str
-
get
(*args)[source]¶ Get a variable from the default section :param *args: dict.get() args :type *args: args
Returns: config variable Return type: str
-
get_ini
(incl_unset=False)[source]¶ Return the config dictionary in INI format :param incl_unset: include variables with no defaults. :type incl_unset: bool
Returns: string of the config file in INI format Return type: str
-
get_section
(*args)[source]¶ get a section dictionary Args:
Returns: section config dictionary Return type: dict
-
load
()[source]¶ Load all configurations from available resources, skip if empty:
default`
dict passed toConfigLoad.__init__()
.- Custom paths as defined in
CONFS_PATH
in constants
.
- Custom paths as defined in
- XDG standard paths.
- Environment variables.
Returns: dict of dicts. Return type: dict
-
update_args
(args)[source]¶ Update config dictionary with parsed args, as resolved by argparse. Only root positional arguments that already exist will overridden.
Parameters: args (namespace) – args parsed by argparse
-
update_parser
(parser)[source]¶ Update config dictionary with declared arguments in an argparse.parser New variables will be created, and existing ones overridden.
Parameters: parser (argparse.ArgumentParser) – parser to read variables from
-
-
lago.config.
_get_configs_path
()[source]¶ Get a list of possible configuration files, from the following sources: 1. All files that exists in constants.CONFS_PATH. 2. All XDG standard config files for “lago.conf”, in reversed order of importance.
Returns: list of files Return type: list(str)
-
lago.config.
get_env_dict
(root_section)[source]¶ Read all Lago variables from the environment. The lookup format is: LAGO_VARNAME - will land into ‘lago’ section LAGO__SECTION1__VARNAME - will land into ‘section1’ section, notice the double ‘__’. LAGO__LONG_SECTION_NAME__VARNAME - will land into ‘long_section_name’
Returns: dict of section configuration dicts Return type: dict Examples
>>> os.environ['LAGO_GLOBAL_VAR'] = 'global' >>> os.environ['LAGO__INIT__REPO_PATH'] = '/tmp/store' >>> >>> config.get_env_dict() {'init': {'repo_path': '/tmp/store'}, 'lago': {'global_var': 'global'}}
lago.constants module¶
-
lago.constants.
CONFS_PATH
= ['/etc/lago/lago.conf']¶ CONFS_PATH - default path to first look for configuration files.
-
lago.constants.
LIBEXEC_DIR
= '/usr/libexec/lago/'¶ LIBEXEC_DIR -
lago.export module¶
-
class
lago.export.
DiskExportManager
(dst, disk_type, disk, do_compress)[source]¶ Bases:
object
DiskExportManager object is responsible on the export process of an image from the current Lago prefix.
DiskExportManger is the base class of specific DiskExportManger. Each specific DiskExportManger is responsible on the export process of an image with a specific type (e.g template, file...)
-
src
¶ str – Path to the image that should be exported
-
name
¶ str – The name of the exported disk
-
dst
¶ str – The absolute path of the exported disk
-
disk_type
¶ str – The type of the image e.g template, file, empty...
-
disk
¶ dict – Disk attributes (of the disk that should be exported) as found in workdir/current/virt/VM-NAME
-
exported_metadata
¶ dict – A copy of the source disk metadata, this dict should be updated with new values during the export process.
-
do_compress
¶ bool – If true, apply compression to the exported disk.
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
calc_sha
(checksum)[source]¶ Calculate the checksum of the new exported disk, write it to a file, and update this managers ‘exported_metadata’.
Parameters: checksum (str) – The type of the checksum
-
export
()[source]¶ This method will handle the export process and should implemented in each subclass.
-
static
get_instance_by_type
(dst, disk, do_compress, *args, **kwargs)[source]¶ Parameters: - Returns
- An instance of a subclass of DiskExportManager which matches the disk type.
-
-
class
lago.export.
FileExportManager
(dst, disk_type, disk, do_compress, *args, **kwargs)[source]¶ Bases:
lago.export.DiskExportManager
FileExportManager is responsible exporting images of type file and empty.
-
standalone
¶ bool – If true, create a new image which is the result of merging all the layers of src (the image that we want to export).
-
src_qemu_info
¶ dict – Metadata on src which was generated by qemu-img.
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
-
class
lago.export.
TemplateExportManager
(dst, disk_type, disk, do_compress, *args, **kwargs)[source]¶ Bases:
lago.export.DiskExportManager
TemplateExportManager is responsible exporting images of type template.
-
See superclass
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
-
class
lago.export.
VMExportManager
(disks, dst, compress, with_threads=True, *args, **kwargs)[source]¶ Bases:
object
VMExportManager object is responsible on the export process of a list of disks.
-
disks
¶ list of dicts – Disks to export.
-
dst
¶ str – Where to place the exported disks.
-
compress
¶ bool – If True compress each exported disk.
-
with_threads
¶ bool – If True, run the export in parallel
-
*args
list – Extra args, will be passed to each DiskExportManager
-
**kwargs
dict – Extra args, will be passed to each DiskExportManager
-
_get_export_mgr
()[source]¶ Returns: Handler for each disk Return type: (DiskExportManager)
-
collect_paths
()[source]¶ Returns: The path of the disks that will be exported. Return type: (list of str)
-
lago.guestfs_tools module¶
-
lago.guestfs_tools.
extract_paths
(disk_path, disk_root, paths, ignore_nopath)[source]¶ Extract paths from a disk using guestfs
Parameters: Returns: None
Raises: ExtractPathNoPathError
– if a none existing path was found on the VM, and ignore_nopath is False.ExtractPathError
– on all other failures.
lago.lago_ansible module¶
-
class
lago.lago_ansible.
LagoAnsible
(prefix)[source]¶ Bases:
object
A class for handling Ansible related tasks
-
prefix
¶ lago.prefix.Prefix – The prefix that this object wraps
-
_generate_entry
(vm)[source]¶ Generate host entry for the given VM :param vm: The VM for which the entry
should be created for.Returns: An entry for vm Return type: str
-
get_inventory
(keys=None)[source]¶ Create an Ansible inventory based on python dicts and lists. The returned value is a dict in which every key represents a group and every value is a list of entries for that group.
Parameters: keys (list of str) – Path to the keys that will be used to create groups. Returns: dict based Ansible inventory Return type: dict
-
get_inventory_str
(keys=None)[source]¶ Convert a dict generated by ansible.LagoAnsible.get_inventory to an INI-like file.
Parameters: keys (list of str) – Path to the keys that will be used to create groups. Returns: INI-like Ansible inventory Return type: str
-
get_inventory_temp_file
(*args, **kwds)[source]¶ Context manager which returns the inventory written on a tempfile. The tempfile will be deleted as soon as this context manger ends.
Parameters: keys (list of str) – Path to the keys that will be used to create groups. Yields: tempfile.NamedTemporaryFile – Temp file containing the inventory
-
lago.log_utils module¶
This module defines the special logging tools that lago uses
-
lago.log_utils.
ALWAYS_SHOW_REG
= <_sre.SRE_Pattern object>¶ Regexp that will match the above template
-
lago.log_utils.
ALWAYS_SHOW_TRIGGER_MSG
= 'force-show:%s'¶ Message template that will always shoud the messago
-
class
lago.log_utils.
ColorFormatter
(fmt=None, datefmt=None)[source]¶ Bases:
logging.Formatter
Formatter to add colors to log records
-
CRITICAL
= '\x1b[31m'¶
-
CYAN
= '\x1b[36m'¶
-
DEBUG
= ''¶
-
DEFAULT
= '\x1b[0m'¶
-
ERROR
= '\x1b[31m'¶
-
GREEN
= '\x1b[32m'¶
-
INFO
= '\x1b[36m'¶
-
NONE
= ''¶
-
RED
= '\x1b[31m'¶
-
WARNING
= '\x1b[33m'¶
-
WHITE
= '\x1b[37m'¶
-
YELLOW
= '\x1b[33m'¶
-
classmethod
colored
(color, message)[source]¶ Small function to wrap a string around a color
Parameters: Returns: the colored string
Return type:
-
format
(record)[source]¶ Adds colors to a log record and formats it with the default
Parameters: record (logging.LogRecord) – log record to format Returns: The colored and formatted record string Return type: str
-
-
class
lago.log_utils.
ContextLock
[source]¶ Bases:
object
Context manager to thread lock a block of code
-
lago.log_utils.
END_TASK_MSG
= 'Success'¶ Message to be shown when a task is ended
-
lago.log_utils.
END_TASK_REG
= <_sre.SRE_Pattern object>¶ Regexp that will match the above template
-
lago.log_utils.
END_TASK_TRIGGER_MSG
= 'end task%s'¶ Message template that will trigger a task end
-
class
lago.log_utils.
LogTask
(task, logger=<module 'logging' from '/usr/lib/python2.7/logging/__init__.pyc'>, level='info', propagate_fail=True, uuid=None)[source]¶ Bases:
object
Context manager for a log task
Example
>>> with LogTask('mytask'): ... pass
-
lago.log_utils.
START_TASK_MSG
= ''¶ Message to be shown when a task is started
-
lago.log_utils.
START_TASK_REG
= <_sre.SRE_Pattern object>¶ Regexp that will match the above template
-
lago.log_utils.
START_TASK_TRIGGER_MSG
= 'start task%s'¶ Message template that will trigger a task
-
class
lago.log_utils.
Task
(name, *args, **kwargs)[source]¶ Bases:
collections.deque
Small wrapper around deque to add the failed status and name to a task
-
name
¶ str – name for this task
-
failed
¶ bool – If this task has failed or not (if there was any error log shown during it’s execution)
-
force_show
¶ bool – If set, will show any log records generated inside this task even if it’s out of nested depth limit
-
-
class
lago.log_utils.
TaskHandler
(initial_depth=0, task_tree_depth=-1, buffer_size=2000, dump_level=40, level=0, formatter=<class 'lago.log_utils.ColorFormatter'>)[source]¶ Bases:
logging.StreamHandler
This log handler will use the concept of tasks, to hide logs, and will show all the logs for the current task if there’s a logged error while running that task.
It will hide any logs that belong to nested tasks that have more than
task_tree_depth
parent levels, and for the ones that are above that level, it will show only the logs that have a loglevel abovelevel
.You can force showing a log record immediately if you use the
log_always()
function bypassing all the filters.If there’s a log record with log level higher than
dump_level
it will be considered a failure, and all the logs for the current task that have a log level abovelevel
will be shown no matter at which depth the task belongs to. Also, all the parent tasks will be tagged as error.-
formatter
¶ logging.LogFormatter – formatter to use
-
initial_depth
¶ int – Initial depth to account for, in case this handler was created in a subtask
-
tasks_by_thread (dict of str
OrderedDict of str: Task): List of thread names, and their currently open tasks with their latest log records
-
dump_level
¶ int – log level from which to consider a log record as error
-
buffer_size
¶ int – Size of the log record deque for each task, the bigger, the more records it can show in case of error but the more memory it will use
-
task_tree_depth
¶ int – number of the nested level to show start/end task logs for, if -1 will show always
-
level
¶ int – Log level to show logs from if the depth limit is not reached
-
main_failed
¶ bool – used to flag from a child thread that the main should fail any current task
-
_tasks_lock
¶ ContextLock – Lock for the tasks_by_thread dict
-
_main_thread_lock
¶ ContextLock – Lock for the main_failed bool
-
TASK_INDICATORS
= ['@', '#', '*', '-', '~']¶ List of chars to show as task prefix, to ease distinguishing them
-
close_children_tasks
(parent_task_name)[source]¶ Closes all the children tasks that were open
Parameters: parent_task_name (str) – Name of the parent task Returns: None
-
emit
(record)[source]¶ Handle the given record, this is the entry point from the python logging facility
- Params:
- record (logging.LogRecord): log record to handle
Returns: None
-
get_task_indicator
(task_level=None)[source]¶ Parameters: task_level (int or None) – task depth level to get the indicator for, if None, will use the current tasks depth Returns: char to prepend to the task logs to indicate it’s level Return type: str
-
get_tasks
(thread_name)[source]¶ Parameters: thread_name (str) – name of the thread to get the tasks for Returns: - list of task names and log records for
- each for the given thread
Return type: OrderedDict of str, Task
-
handle_closed_task
(task_name, record)[source]¶ Do everything needed when a task is closed
- Params:
- task_name (str): name of the task that is finishing record (logging.LogRecord): log record with all the info
Returns: None
-
handle_new_task
(task_name, record)[source]¶ Do everything needed when a task is starting
- Params:
- task_name (str): name of the task that is starting record (logging.LogRecord): log record with all the info
Returns: None
-
mark_main_tasks_as_failed
()[source]¶ Flags to the main thread that all it’s tasks sholud fail
Returns: None
-
mark_parent_tasks_as_failed
(task_name, flush_logs=False)[source]¶ Marks all the parent tasks as failed
Parameters: Returns: None
-
pretty_emit
(record, is_header=False, task_level=None)[source]¶ Wrapper around the
logging.StreamHandler
emit method to add some decoration stuff to the messageParameters: - record (logging.LogRecord) – log record to emit
- is_header (bool) – if this record is a header, usually, a start or end task message
- task_level (int) – If passed, will take that as the current nested task level instead of calculating it from the current tasks
Returns: None
-
should_show_by_depth
(cur_level=None)[source]¶ Parameters: cur_level (int) – depth level to take into account Returns: - True if the given depth level should show messages (not
- taking into account the log level)
Return type: bool
-
should_show_by_level
(record_level, base_level=None)[source]¶ Parameters: - record_level (int) – log level of the record to check
- base_level (int or None) – log level to check against, will use the
object’s
dump_level
if None is passed
Returns: - True if the given log record should be shown according to the
log level
Return type:
-
tasks
¶ Returns –
- OrderedDict of str, Task: list of task names and log records for
- each for the current thread
-
-
lago.log_utils.
end_log_task
(task, logger=<module 'logging' from '/usr/lib/python2.7/logging/__init__.pyc'>, level='info')[source]¶ Ends a log task
Parameters: - task (str) – name of the log task to end
- logger (logging.Logger) – logger to use
- level (str) – log level to use
Returns: None
-
lago.log_utils.
hide_stevedore_logs
()[source]¶ Hides the logs of stevedore, this function was added in order to support older versions of stevedore
We are using the NullHandler in order to get rid from ‘No handlers could be found for logger...’ msg
Returns: None
-
lago.log_utils.
log_always
(message)[source]¶ Wraps the given message with a tag that will make it be always logged by the task logger
Parameters: message (str) – message to wrap with the tag Returns: - tagged message that will get it shown immediately by the task
- logger
Return type: str
-
lago.log_utils.
log_task
(task, logger=<module 'logging' from '/usr/lib/python2.7/logging/__init__.pyc'>, level='info', propagate_fail=True, uuid=None)[source]¶ Parameterized decorator to wrap a function in a log task
Example
>>> @log_task('mytask') ... def do_something(): ... pass
-
lago.log_utils.
setup_prefix_logging
(logdir)[source]¶ Sets up a file logger that will create a log in the given logdir (usually a lago prefix)
Parameters: logdir (str) – path to create the log into, will be created if it does not exist Returns: None
-
lago.log_utils.
start_log_task
(task, logger=<module 'logging' from '/usr/lib/python2.7/logging/__init__.pyc'>, level='info')[source]¶ Starts a log task
Parameters: - task (str) – name of the log task to start
- logger (logging.Logger) – logger to use
- level (str) – log level to use
Returns: None
lago.prefix module¶
lago.sdk module¶
lago.sdk_utils module¶
-
class
lago.sdk_utils.
SDKMethod
(name)[source]¶ Bases:
object
Metadata to store inside the decorated function
-
class
lago.sdk_utils.
SDKWrapper
[source]¶ Bases:
sphinx.ext.autodoc.ObjectProxy
A proxy object that exposes only methods which were decorated with
expose()
decorator.
-
lago.sdk_utils.
expose
(func)[source]¶ Decorator to be used with
SDKWrapper
. This decorator indicates that the wrapped method or class should be exposed in the proxied object.Parameters: func (types.FunctionType/types.MethodType) – function to decorate Returns: None
lago.service module¶
-
class
lago.service.
SysVInitService
(vm, name)[source]¶ Bases:
lago.plugins.service.ServicePlugin
-
BIN_PATH
= '/sbin/service'¶
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
-
class
lago.service.
SystemdContainerService
(vm, name)[source]¶ Bases:
lago.plugins.service.ServicePlugin
-
BIN_PATH
= '/usr/bin/docker'¶
-
HOST_BIN_PATH
= '/usr/bin/systemctl'¶
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
-
class
lago.service.
SystemdService
(vm, name)[source]¶ Bases:
lago.plugins.service.ServicePlugin
-
BIN_PATH
= '/usr/bin/systemctl'¶
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-
lago.ssh module¶
-
lago.ssh.
drain_ssh_channel
(chan, stdin=None, stdout=<open file '<stdout>', mode 'w'>, stderr=<open file '<stderr>', mode 'w'>)[source]¶
-
lago.ssh.
get_ssh_client
(ip_addr, ssh_key=None, host_name=None, ssh_tries=None, propagate_fail=True, username='root', password='123456')[source]¶
-
lago.ssh.
interactive_ssh
(ip_addr, command=None, host_name=None, ssh_key=None, username='root', password='123456')[source]¶
-
lago.ssh.
interactive_ssh_channel
(chan, command=None, stdin=<open file '<stdin>', mode 'r'>)[source]¶
-
lago.ssh.
ssh
(ip_addr, command, host_name=None, data=None, show_output=True, propagate_fail=True, tries=None, ssh_key=None, username='root', password='123456')[source]¶
lago.subnet_lease module¶
lago.sysprep module¶
-
lago.sysprep.
sysprep
(disk, distro, loader=None, backend='direct', **kwargs)[source]¶ Run virt-sysprep on the
disk
, commands are built from the distro specific template and arguments passed inkwargs
. If no template is available it will default tosysprep-base.j2
.Parameters: Returns: None
Raises: RuntimeError
– On virt-sysprep none 0 exit code.
lago.templates module¶
This module contains any disk template related classes and functions, including the repository store manager classes and template providers, some useful definitions:
- Template repositories:
- Repository where to fetch templates from, as an http server
- Template store:
- Local store to cache templates
- Template:
- Unititialized disk image to use as base for other disk images
- Template version:
- Specific version of a template, to allow getting updates without having to change the template name everywhere
-
class
lago.templates.
FileSystemTemplateProvider
(root)[source]¶ Handles file type templates, that is, getting a disk template from the host’s filesystem
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_prefixed
(*path)[source]¶ Join all the given paths prefixed with this provider’s base root path
Parameters: *path (str) – sections of the path to join, passed as positional arguments Returns: Joined paths prepended with the provider root path Return type: str
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download_image
(handle, dest)[source]¶ Copies over the handl to the destination
Parameters: Returns: None
-
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class
lago.templates.
HttpTemplateProvider
(baseurl)[source]¶ This provider allows the usage of http urls for templates
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download_image
(handle, dest)[source]¶ Downloads the image from the http server
Parameters: Returns: None
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get_hash
(handle)[source]¶ Get the associated hash for the given handle, the hash file must exist (
handle + '.hash'
).Parameters: handle (str) – Path to the template to get the hash from Returns: Hash for the given handle Return type: str
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get_metadata
(handle)[source]¶ Returns the associated metadata info for the given handle, the metadata file must exist (
handle + '.metadata'
). If the given handle has an.xz
extension, it will get removed when calculating the handle metadata pathParameters: handle (str) – Path to the template to get the metadata from Returns: Metadata for the given handle Return type: dict
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open_url
(url, suffix='', dest=None)[source]¶ Opens the given url, trying the compressed version first. The compressed version url is generated adding the
.xz
extension to theurl
and adding the given suffix after that.xz
extension. If dest passed, it will download the data to that path if ableParameters: Returns: - response object to read from (lazy read), closed
if no dest passed
Return type: urllib.addinfourl
Raises: RuntimeError
– if the url gave http error when retrieving it
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-
class
lago.templates.
Template
(name, versions)[source]¶ Disk image template class
-
name
¶ str – Name of this template
-
_versions (dict(str
TemplateVersion)): versions for this template
-
get_latest_version
()[source]¶ Retrieves the latest version for this template, the latest being the one with the newest timestamp
Returns: TemplateVersion
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get_version
(ver_name=None)[source]¶ Get the given version for this template, or the latest
Parameters: ver_name (str or None) – Version to retieve, None for the latest Returns: - The version matching the given name or the latest
- one
Return type: TemplateVersion
-
-
class
lago.templates.
TemplateRepository
(dom)[source]¶ A template repository is a single source for templates, that uses different providers to actually retrieve them. That means for example that the ‘ovirt’ template repository, could support the ‘http’ and a theoretical ‘gluster’ template providers.
-
_dom
¶ dict – Specification of the template
-
_providers
¶ dict – Providers instances for any source in the spec
-
_get_provider
(spec)[source]¶ Get the provider for the given template spec
Parameters: spec (dict) – Template spec Returns: A provider instance for that spec Return type: HttpTemplateProvider or FileSystemTemplateProvider
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classmethod
from_url
(path)[source]¶ Instantiate a
TemplateRepository
instance from the data in a file or urlParameters: path (str) – Path or url to the json file to load Returns: A new instance Return type: TemplateRepository
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-
class
lago.templates.
TemplateStore
(path)[source]¶ Local cache to store templates
The store uses various files to keep track of the templates cached, access and versions. An example template store looks like:
$ tree /var/lib/lago/store/ /var/lib/lago/store/ ├── in_office_repo:centos6_engine:v2.tmp ├── in_office_repo:centos7_engine:v5.tmp ├── in_office_repo:fedora22_host:v2.tmp ├── phx_repo:centos6_engine:v2 ├── phx_repo:centos6_engine:v2.hash ├── phx_repo:centos6_engine:v2.metadata ├── phx_repo:centos6_engine:v2.users ├── phx_repo:centos7_engine:v4.tmp ├── phx_repo:centos7_host:v4.tmp └── phx_repo:storage-nfs:v1.tmp
There you can see the files:
- *.tmp
- Temporary file created while downloading the template from the repository (depends on the provider)
- ${repo_name}:${template_name}:${template_version}
- This file is the actual disk image template
- *.hash
- Cached hash for the template disk image
- *.metadata
- Metadata for this template image in json format, usually this includes the distro and root-password
-
__contains__
(temp_ver)[source]¶ Checks if a given version is in this store
Parameters: temp_ver (TemplateVersion) – Version to look for Returns: True
if the version is in this storeReturn type: bool
-
_prefixed
(*path)[source]¶ Join the given paths and prepend this stores path
Parameters: *path (str) – list of paths to join, as positional arguments Returns: all the paths joined and prepended with the store path Return type: str
-
download
(temp_ver, store_metadata=True)[source]¶ Retrieve the given template version
Parameters: - temp_ver (TemplateVersion) – template version to retrieve
- store_metadata (bool) – If set to
False
, will not refresh the local metadata with the retrieved one
Returns: None
-
get_path
(temp_ver)[source]¶ Get the path of the given version in this store
Parameters: TemplateVersion (temp_ver) – version to look for Returns: The path to the template version inside the store Return type: str Raises: RuntimeError
– if the template is not in the store
-
get_stored_hash
(temp_ver)[source]¶ Retrieves the hash for the given template version from the store
Parameters: temp_ver (TemplateVersion) – template version to retrieve the hash for Returns: hash of the given template version Return type: str
-
get_stored_metadata
(temp_ver)[source]¶ Retrieves the metadata for the given template version from the store
Parameters: temp_ver (TemplateVersion) – template version to retrieve the metadata for Returns: the metadata of the given template version Return type: dict
-
class
lago.templates.
TemplateVersion
(name, source, handle, timestamp)[source]¶ Each template can have multiple versions, each of those is actually a different disk template file representation, under the same base name.
-
download
(destination)[source]¶ Retrieves this template to the destination file
Parameters: destination (str) – file path to write this template to Returns: None
-
get_hash
()[source]¶ Returns the associated hash for this template version
Returns: Hash for this version Return type: str
-
-
lago.templates.
_locked
(func)[source]¶ Decorator that ensures that the decorated function has the lock of the repo while running, meant to decorate only bound functions for classes that have lock_path method.
-
lago.templates.
find_repo_by_name
(name, repo_dir=None)[source]¶ Searches the given repo name inside the repo_dir (will use the config value ‘template_repos’ if no repo dir passed), will rise an exception if not found
Parameters: Returns: path to the repo
Return type: Raises: RuntimeError
– if not found
lago.utils module¶
-
class
lago.utils.
CommandStatus
[source]¶ Bases:
lago.utils.CommandStatus
-
exception
lago.utils.
LagoException
[source]¶ Bases:
exceptions.Exception
-
exception
lago.utils.
LagoInitException
[source]¶ Bases:
lago.utils.LagoException
-
exception
lago.utils.
LagoUserException
[source]¶ Bases:
lago.utils.LagoException
-
class
lago.utils.
LockFile
(path, timeout=None, **kwargs)[source]¶ Bases:
object
Context manager that creates a lock around a directory, with optional timeout in the acquire operation
Parameters: -
__enter__
()[source]¶ Start the lock with timeout if needed in the acquire operation
Raises: TimerException
– if the timeout is reached before acquiring the lock
-
-
class
lago.utils.
RollbackContext
(*args)[source]¶ Bases:
object
A context manager for recording and playing rollback. The first exception will be remembered and re-raised after rollback
Sample usage: > with RollbackContext() as rollback: > step1() > rollback.prependDefer(lambda: undo step1) > def undoStep2(arg): pass > step2() > rollback.prependDefer(undoStep2, arg)
More examples see tests/utilsTests.py @ vdsm code
-
exception
lago.utils.
TimerException
[source]¶ Bases:
exceptions.Exception
Exception to throw when a timeout is reached
-
lago.utils.
_CommandStatus
¶ alias of
CommandStatus
-
lago.utils.
_run_command
(command, input_data=None, stdin=None, out_pipe=-1, err_pipe=-1, env=None, uuid=None, **kwargs)[source]¶ Runs a command
Parameters: - command (list of str) – args of the command to execute, including the command itself as command[0] as [‘ls’, ‘-l’]
- input_data (str) – If passed, will feed that data to the subprocess through stdin
- out_pipe (int or file) – File descriptor as passed to :ref:subprocess.Popen to use as stdout
- stdin (int or file) – File descriptor as passed to :ref:subprocess.Popen to use as stdin
- err_pipe (int or file) – File descriptor as passed to :ref:subprocess.Popen to use as stderr
- of str (env(dict) – str): If set, will use the given dict as env for the subprocess
- uuid (uuid) – If set the command will be logged with the given uuid converted to string, otherwise, a uuid v4 will be generated.
- **kwargs – Any other keyword args passed will be passed to the :ref:subprocess.Popen call
Returns: result of the interactive execution
Return type:
-
lago.utils.
deepcopy
(original_obj)[source]¶ Creates a deep copy of an object with no crossed referenced lists or dicts, useful when loading from yaml as anchors generate those cross-referenced dicts and lists
Parameters: original_obj (object) – Object to deep copy Returns: deep copy of the object Return type: object
-
lago.utils.
filter_spec
(spec, paths, wildcard='*', separator='/')[source]¶ Remove keys from a spec file. For example, with the following path: domains//disks//metadata all the metadata dicts from all domains disks will be removed.
Parameters: Returns: None
Raises: utils.LagoUserException
– If a malformed path was detected
-
lago.utils.
get_hash
(file_path, checksum='sha1')[source]¶ Generate a hash for the given file
Parameters: Returns: hash for that file
Return type:
-
lago.utils.
get_qemu_info
(path, backing_chain=False, fail_on_error=True)[source]¶ Get info on a given qemu disk
Parameters: - path (str) – Path to the required disk
- backing_chain (boo) – if true, include also info about
- image predecessors. (the) –
Returns: if backing_chain == True then a list of dicts else a dict
Return type:
-
lago.utils.
load_virt_stream
(virt_fd)[source]¶ Loads the given conf stream into a dict, trying different formats if needed
Parameters: virt_fd (str) – file like objcect with the virt config to load Returns: Loaded virt config Return type: dict
-
lago.utils.
qemu_rebase
(target, backing_file, safe=True, fail_on_error=True)[source]¶ changes the backing file of ‘source’ to ‘backing_file’ If backing_file is specified as “” (the empty string), then the image is rebased onto no backing file (i.e. it will exist independently of any backing file). (Taken from qemu-img man page)
Parameters:
-
lago.utils.
run_command
(command, input_data=None, out_pipe=-1, err_pipe=-1, env=None, **kwargs)[source]¶ Runs a command non-interactively
Parameters: - command (list of str) – args of the command to execute, including the command itself as command[0] as [‘ls’, ‘-l’]
- input_data (str) – If passed, will feed that data to the subprocess through stdin
- out_pipe (int or file) – File descriptor as passed to :ref:subprocess.Popen to use as stdout
- err_pipe (int or file) – File descriptor as passed to :ref:subprocess.Popen to use as stderr
- of str (env(dict) – str): If set, will use the given dict as env for the subprocess
- **kwargs – Any other keyword args passed will be passed to the :ref:subprocess.Popen call
Returns: result of the interactive execution
Return type:
-
lago.utils.
run_command_with_validation
(cmd, fail_on_error=True, msg='An error has occurred')[source]¶
-
lago.utils.
run_interactive_command
(command, env=None, **kwargs)[source]¶ Runs a command interactively, reusing the current stdin, stdout and stderr
Parameters: - command (list of str) – args of the command to execute, including the command itself as command[0] as [‘ls’, ‘-l’]
- of str (env(dict) – str): If set, will use the given dict as env for the subprocess
- **kwargs – Any other keyword args passed will be passed to the :ref:subprocess.Popen call
Returns: result of the interactive execution
Return type:
lago.validation module¶
lago.virt module¶
-
class
lago.virt.
VirtEnv
(prefix, vm_specs, net_specs)[source]¶ Bases:
object
Env properties: * prefix * vms * net
- libvirt_con
-
_get_stop_shutdown_common_args
(vm_names)[source]¶ Get the common arguments for stop and shutdown commands
Parameters: vm_names (list of str) – The names of the requested vms - Returns
- list of plugins.vm.VMProviderPlugin:
- vms objects that should be stopped
list of virt.Network: net objects that should be stopped str: log message
Raises: utils.LagoUserException
– If a vm name doesn’t exist
-
_get_unused_nets
(vms_to_stop)[source]¶ Return a list of nets that used only by the vms in vms_to_stop
Parameters: vms_to_stop (list of str) – The names of the requested vms - Returns
- list of virt.Network: net objects that used only by
- vms in vms_to_stop
Raises: utils.LagoUserException
– If a vm name doesn’t exist
-
export_vms
(vms_names, standalone, dst_dir, compress, init_file_name, out_format, collect_only=False, with_threads=True)[source]¶
-
generate_init
(dst, out_format, vms_to_include, filters=None)[source]¶ Generate an init file which represents this env and can be used with the images created by self.export_vms
Parameters: - dst (str) – path and name of the new init file
- out_format (plugins.output.OutFormatPlugin) – formatter for the output (the default is yaml)
- filters (list) – list of paths to keys that should be removed from the init file
- (list of (vms_to_include) – class:lago.plugins.vm.VMPlugin): list of vms to include in the init file
Returns: None
-
get_compat
()[source]¶ Get compatibility level for this environment - which is the Lago version used to create this environment
-
get_env_spec
(filters=None)[source]¶ Get the spec of the current env. The spec will hold the info about all the domains and networks associated with this env.
Parameters: filters (list) – list of paths to keys that should be removed from the init file Returns: the spec of the current env Return type: dict
-
get_snapshots
(domains=None)[source]¶ Get the list of snapshots for each domain
Parameters: - domanins (list of str) – list of the domains to get the snapshots
- all will be returned if none or empty list passed (for,) –
Returns: with the domain names and the list of snapshots for each
Return type: dict of str -> list(str)
-
get_vms
(vm_names=None)[source]¶ Returns the vm objects associated with vm_names if vm_names is None, return all the vms in the prefix
Parameters: vm_names (list of str) – The names of the requested vms - Returns
- dict: Which contains the requested vm objects indexed by name
Raises: utils.LagoUserException
– If a vm name doesn’t exist
lago.vm module¶
-
class
lago.vm.
DefaultVM
(env, spec)[source]¶ Bases:
lago.plugins.vm.VMPlugin
-
_abc_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache
= <_weakrefset.WeakSet object>¶
-
_abc_negative_cache_version
= 33¶
-
_abc_registry
= <_weakrefset.WeakSet object>¶
-