lsst.pex.config  19.0.0-5-g9aa49c1+2
Public Member Functions | List of all members
pex.config.configField.ConfigField Class Reference
Inheritance diagram for pex.config.configField.ConfigField:
pex.config.config.Field

Public Member Functions

def __init__ (self, doc, dtype, default=None, check=None, deprecated=None)
 
def __get__ (self, instance, owner=None)
 
def __set__ (self, instance, value, at=None, label="assignment")
 
def rename (self, instance)
 
def save (self, outfile, instance)
 
def freeze (self, instance)
 
def toDict (self, instance)
 
def validate (self, instance)
 
- Public Member Functions inherited from pex.config.config.Field
def __init__ (self, doc, dtype, default=None, check=None, optional=False, deprecated=None)
 
def rename (self, instance)
 
def validate (self, instance)
 
def freeze (self, instance)
 
def save (self, outfile, instance)
 
def toDict (self, instance)
 
def __get__ (self, instance, owner=None, at=None, label="default")
 
def __set__ (self, instance, value, at=None, label='assignment')
 
def __delete__ (self, instance, at=None, label='deletion')
 

Additional Inherited Members

- Public Attributes inherited from pex.config.config.Field
 dtype
 
 doc
 
 deprecated
 
 default
 
 check
 
 optional
 
 source
 
- Static Public Attributes inherited from pex.config.config.Field
 supportedTypes = set((str, bool, float, int, complex))
 

Detailed Description

A configuration field (`~lsst.pex.config.Field` subclass) that takes a
`~lsst.pex.config.Config`-type as a value.

Parameters
----------
doc : `str`
    A description of the configuration field.
dtype : `lsst.pex.config.Config`-type
    The type of the field, which must be a subclass of
    `lsst.pex.config.Config`.
default : `lsst.pex.config.Config`, optional
    If default is `None`, the field will default to a default-constructed
    instance of ``dtype``. Additionally, to allow for fewer deep-copies,
    assigning an instance of ``ConfigField`` to ``dtype`` itself, is
    considered equivalent to assigning a default-constructed sub-config.
    This means that the argument default can be ``dtype``, as well as an
    instance of ``dtype``.
check : callable, optional
    A callback function that validates the field's value, returning `True`
    if the value is valid, and `False` otherwise.
deprecated : None or `str`, optional
    A description of why this Field is deprecated, including removal date.
    If not None, the string is appended to the docstring for this Field.

See also
--------
ChoiceField
ConfigChoiceField
ConfigDictField
ConfigurableField
DictField
Field
ListField
RangeField
RegistryField

Notes
-----
The behavior of this type of field is much like that of the base `Field`
type.

Assigning to ``ConfigField`` will update all of the fields in the
configuration.

Member Function Documentation

◆ freeze()

def pex.config.configField.ConfigField.freeze (   self,
  instance 
)
Make this field read-only.

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Notes
-----
Freezing is only relevant for fields that hold subconfigs. Fields which
hold subconfigs should freeze each subconfig.

**Subclasses should implement this method.**

◆ rename()

def pex.config.configField.ConfigField.rename (   self,
  instance 
)
Rename the field in a `~lsst.pex.config.Config` (for internal use
only).

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Notes
-----
This method is invoked by the `lsst.pex.config.Config` object that
contains this field and should not be called directly.

Renaming is only relevant for `~lsst.pex.config.Field` instances that
hold subconfigs. `~lsst.pex.config.Fields` that hold subconfigs should
rename each subconfig with the full field name as generated by
`lsst.pex.config.config._joinNamePath`.

◆ save()

def pex.config.configField.ConfigField.save (   self,
  outfile,
  instance 
)
Save this field to a file (for internal use only).

Parameters
----------
outfile : file-like object
    A writeable field handle.
instance : `Config`
    The `Config` instance that contains this field.

Notes
-----
This method is invoked by the `~lsst.pex.config.Config` object that
contains this field and should not be called directly.

The output consists of the documentation string
(`lsst.pex.config.Field.doc`) formatted as a Python comment. The second
line is formatted as an assignment: ``{fullname}={value}``.

This output can be executed with Python.

◆ toDict()

def pex.config.configField.ConfigField.toDict (   self,
  instance 
)
Convert the field value so that it can be set as the value of an
item in a `dict` (for internal use only).

Parameters
----------
instance : `Config`
    The `Config` that contains this field.

Returns
-------
value : object
    The field's value. See *Notes*.

Notes
-----
This method invoked by the owning `~lsst.pex.config.Config` object and
should not be called directly.

Simple values are passed through. Complex data structures must be
manipulated. For example, a `~lsst.pex.config.Field` holding a
subconfig should, instead of the subconfig object, return a `dict`
where the keys are the field names in the subconfig, and the values are
the field values in the subconfig.

◆ validate()

def pex.config.configField.ConfigField.validate (   self,
  instance 
)
Validate the field (for internal use only).

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Raises
------
lsst.pex.config.FieldValidationError
    Raised if verification fails.

Notes
-----
This method provides basic validation:

- Ensures that the value is not `None` if the field is not optional.
- Ensures type correctness.
- Ensures that the user-provided ``check`` function is valid.

Most `~lsst.pex.config.Field` subclasses should call
`lsst.pex.config.field.Field.validate` if they re-implement
`~lsst.pex.config.field.Field.validate`.

The documentation for this class was generated from the following file: