lsst.pipe.base.configOverrides.ConfigOverrides Class Reference

Public Member Functions
def	__init__ (self)
def	addFileOverride (self, filename)
def	addValueOverride (self, field, value)
def	addDatasetNameSubstitution (self, nameDict)
def	applyTo (self, config)

Detailed Description

Defines a set of overrides to be applied to a task config.

Overrides for task configuration need to be applied by activator when
creating task instances. This class represents an ordered set of such
overrides which activator receives from some source (e.g. command line
or some other configuration).

Methods
----------
addFileOverride(filename)
    Add overrides from a specified file.
addValueOverride(field, value)
    Add override for a specific field.
applyTo(config)
    Apply all overrides to a `config` instance.

Notes
-----
Serialization support for this class may be needed, will add later if
necessary.

Definition at line 33 of file configOverrides.py.

Constructor & Destructor Documentation

__init__()

def lsst.pipe.base.configOverrides.ConfigOverrides.__init__

(

self

)

Definition at line 56 of file configOverrides.py.

    def __init__(self):
        self._overrides = []

Member Function Documentation

addDatasetNameSubstitution()

def lsst.pipe.base.configOverrides.ConfigOverrides.addDatasetNameSubstitution	(		self,
			nameDict
	)

Add keys and values to be used in formatting config nameTemplates

This method takes in a dictionary in the format of key:value which
will be used to format fields in all of the nameTemplates found in
a config object. I.E. a nameDictString = {'input': 'deep'} would be
used to format a nameTemplate of "{input}CoaddDatasetProduct".

Parameters
----------
nameDict : `dict`
    a python dict used in formatting nameTemplates

Definition at line 87 of file configOverrides.py.

    def addDatasetNameSubstitution(self, nameDict):
        """Add keys and values to be used in formatting config nameTemplates

        This method takes in a dictionary in the format of key:value which
        will be used to format fields in all of the nameTemplates found in
        a config object. I.E. a nameDictString = {'input': 'deep'} would be
        used to format a nameTemplate of "{input}CoaddDatasetProduct".

        Parameters
        ----------
        nameDict : `dict`
            a python dict used in formatting nameTemplates
        """
        self._overrides += [('namesDict', nameDict)]

addFileOverride()

def lsst.pipe.base.configOverrides.ConfigOverrides.addFileOverride	(		self,
			filename
	)

Add overrides from a specified file.

Parameters
----------
filename : str
    Path to the override file.

Definition at line 59 of file configOverrides.py.

    def addFileOverride(self, filename):
        """Add overrides from a specified file.

        Parameters
        ----------
        filename : str
            Path to the override file.
        """
        self._overrides += [('file', filename)]

addValueOverride()

def lsst.pipe.base.configOverrides.ConfigOverrides.addValueOverride	(		self,
			field,
			value
	)

Add override for a specific field.

This method is not very type-safe as it is designed to support
use cases where input is given as string, e.g. command line
activators. If `value` has a string type and setting of the field
fails with `TypeError` the we'll attempt `eval()` the value and
set the field with that value instead.

Parameters
----------
field : str
    Fully-qualified field name.
value :
    Value to be given to a filed.

Definition at line 69 of file configOverrides.py.

    def addValueOverride(self, field, value):
        """Add override for a specific field.

        This method is not very type-safe as it is designed to support
        use cases where input is given as string, e.g. command line
        activators. If `value` has a string type and setting of the field
        fails with `TypeError` the we'll attempt `eval()` the value and
        set the field with that value instead.

        Parameters
        ----------
        field : str
            Fully-qualified field name.
        value :
            Value to be given to a filed.
        """
        self._overrides += [('value', (field, value))]

applyTo()

def lsst.pipe.base.configOverrides.ConfigOverrides.applyTo	(		self,
			config
	)

Apply all overrides to a task configuration object.

Parameters
----------
config : `pex.Config`

Raises
------
`Exception` is raised if operations on configuration object fail.

Definition at line 102 of file configOverrides.py.

    def applyTo(self, config):
        """Apply all overrides to a task configuration object.

        Parameters
        ----------
        config : `pex.Config`

        Raises
        ------
        `Exception` is raised if operations on configuration object fail.
        """
        for otype, override in self._overrides:
            if otype == 'file':
                config.load(override)
            elif otype == 'value':
                field, value = override
                field = field.split('.')
                # find object with attribute to set, throws if we name is wrong
                obj = config
                for attr in field[:-1]:
                    obj = getattr(obj, attr)
                # If input is a string and field type is not a string then we
                # have to convert string to an expected type. Implementing
                # full string parser is non-trivial so we take a shortcut here
                # and `eval` the string and assign the resulting value to a
                # field. Type erroes can happen during both `eval` and field
                # assignment.
                if isinstance(value, str) and obj._fields[field[-1]].dtype is not str:
                    try:
                        # use safer ast.literal_eval, it only supports literals
                        value = ast.literal_eval(value)
                    except Exception:
                        # eval failed, wrap exception with more user-friendly message
                        raise pexExceptions.RuntimeError(f"Unable to parse `{value}' into a Python object")

                # this can throw in case of type mismatch
                setattr(obj, field[-1], value)
            elif otype == 'namesDict':
                if not isinstance(config, PipelineTaskConfig):
                    raise pexExceptions.RuntimeError("Dataset name substitution can only be used on Tasks "
                                                     "with a ConfigClass that is a subclass of "
                                                     "PipelineTaskConfig")
                config.formatTemplateNames(override)

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

• /j/snowflake/release/lsstsw/stack/Linux64/pipe_base/17.0.1-4-gc69c472+5/python/lsst/pipe/base/configOverrides.py

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