Task¶
- class lsst.pipe.base.Task(config: Config | None = None, *, name: str | None = None, parentTask: Task | None = None, log: logging.Logger | lsst.utils.logging.LsstLogAdapter | None = None)¶
Bases:
object
Base class for data processing tasks.
See Overview of the task framework to learn what tasks are, and Creating a task for more information about writing tasks.
- Parameters:
- config
Task.ConfigClass
instance, optional Configuration for this task (an instance of Task.ConfigClass, which is a task-specific subclass of
lsst.pex.config.Config
, orNone
. IfNone
:If parentTask specified then defaults to parentTask.config.<name>
If parentTask is None then defaults to self.ConfigClass()
- name
str
, optional Brief name of task, or
None
; ifNone
then defaults toTask._DefaultName
- parentTask
Task
-type, optional The parent task of this subtask, if any.
- log
logging.Logger
or subclass, optional Log whose name is used as a log name prefix, or
None
for no prefix. Ignored if is parentTask specified, in which caseparentTask.log
‘s name is used as a prefix. The task’s log name isprefix + "." + name
if a prefix exists, elsename
. The task’s log is then a child logger ofparentTask.log
(ifparentTask
specified), or a child logger of the log from the argument (iflog
is notNone
).
- config
- Raises:
Notes
The constructor must use keyword parameters for everything other than the
config
parameter which can be positional or use keyword form.Useful attributes include:
log
: anlogging.Logger
or subclass.config
: task-specific configuration; an instance ofConfigClass
(see below).metadata
: aTaskMetadata
for collecting task-specific metadata, e.g. data quality and performance metrics. This is data that is only meant to be persisted, never to be used by the task.
Use a
lsst.pipe.base.PipelineTask
subclass to perform I/O with a Butler.Subclasses must also have an attribute
ConfigClass
that is a subclass oflsst.pex.config.Config
which configures the task. Subclasses should also have an attribute_DefaultName
: the default name if there is no parent task._DefaultName
is required for subclasses ofPipeLineTask
and recommended for subclasses of Task because it simplifies construction (e.g. for unit tests).Methods Summary
Empty (clear) the metadata for this Task and all sub-Tasks.
Get metadata for all tasks.
Get the task name as a hierarchical name including parent task names.
getName
()Get the name of the task.
Get a dictionary of all tasks as a shallow copy.
makeField
(doc)Make a
lsst.pex.config.ConfigurableField
for this task.makeSubtask
(name, **keyArgs)Create a subtask as a new instance as the
name
attribute of this task.timer
(name[, logLevel])Context manager to log performance data for an arbitrary block of code.
Methods Documentation
- getFullMetadata() TaskMetadata ¶
Get metadata for all tasks.
- Returns:
- metadata
TaskMetadata
The keys are the full task name. Values are metadata for the top-level task and all subtasks, sub-subtasks, etc.
- metadata
Notes
The returned metadata includes timing information (if
@timer.timeMethod
is used) and any metadata set by the task. The name of each item consists of the full task name with.
replaced by:
, followed by.
and the name of the item, e.g.:topLevelTaskName:subtaskName:subsubtaskName.itemName
using
:
in the full task name disambiguates the rare situation that a task has a subtask and a metadata item with the same name.
- getFullName() str ¶
Get the task name as a hierarchical name including parent task names.
- Returns:
- fullName
str
The full name consists of the name of the parent task and each subtask separated by periods. For example:
The full name of top-level task “top” is simply “top”.
The full name of subtask “sub” of top-level task “top” is “top.sub”.
The full name of subtask “sub2” of subtask “sub” of top-level task “top” is “top.sub.sub2”.
- fullName
- getTaskDict() dict[str, weakref.ReferenceType[lsst.pipe.base.task.Task]] ¶
Get a dictionary of all tasks as a shallow copy.
- Returns:
- taskDict
dict
Dictionary containing full task name: task object for the top-level task and all subtasks, sub-subtasks, etc.
- taskDict
- classmethod makeField(doc: str) ConfigurableField ¶
Make a
lsst.pex.config.ConfigurableField
for this task.- Parameters:
- doc
str
Help text for the field.
- doc
- Returns:
- configurableField
lsst.pex.config.ConfigurableField
A
ConfigurableField
for this task.
- configurableField
Examples
Provides a convenient way to specify this task is a subtask of another task.
Here is an example of use:
class OtherTaskConfig(lsst.pex.config.Config): aSubtask = ATaskClass.makeField("brief description of task")
- makeSubtask(name: str, **keyArgs: Any) None ¶
Create a subtask as a new instance as the
name
attribute of this task.- Parameters:
- name
str
Brief name of the subtask.
- **keyArgs
Extra keyword arguments used to construct the task. The following arguments are automatically provided and cannot be overridden:
config
.parentTask
.
- name
Notes
The subtask must be defined by
Task.config.name
, an instance ofConfigurableField
orRegistryField
.