Association

class jwst.associations.Association(version_id=None)

Bases: MutableMapping

Association Base Class

Parameters:

version_id (str or None) – Version ID to use in the name of this association. If None, nothing is added.

Raises:

AssociationError – If an item doesn’t match.

instance

The instance is the association data structure. See data below

Type:

dict-like

meta

Information about the association.

Type:

dict

data

The association. The format of this data structure is determined by the individual associations and, if defined, validated against their specified schema.

Type:

dict

schema_file

The name of the output schema that an association must adhere to.

Type:

str

Attributes Summary

DEFAULT_EVALUATE	Default do not evaluate input values
DEFAULT_FORCE_UNIQUE	Default whether to force constraints to use unique values.
DEFAULT_REQUIRE_CONSTRAINT	Default require that the constraint exists or otherwise can be explicitly checked.
GLOBAL_CONSTRAINT	Global constraints
INVALID_VALUES	Attribute values that indicate the attribute is not specified.
asn_name	Suggest filename for the association
asn_rule	Name of the rule
ioregistry	The association IO registry
is_valid	Check if association is valid
registry	Registry this rule has been placed in.

Methods Summary

add(item[, check_constraints])	Add the item to the association
check_and_set_constraints(item)	Check whether the given dictionaries match parameters for for this association
create(item[, version_id])	Create association if item belongs
dump([format])	Serialize the association
finalize()	Finalize association
is_item_member(item)	Check if item is already a member of this association
items()
keys()
load(serialized[, format, validate])	Marshall a previously serialized association
match_constraint(item, constraint, conditions)	Generic constraint checking
validate(asn)	Validate an association against this rule
values()

Attributes Documentation

DEFAULT_EVALUATE = False

Default do not evaluate input values

DEFAULT_FORCE_UNIQUE = False

Default whether to force constraints to use unique values.

DEFAULT_REQUIRE_CONSTRAINT = True

Default require that the constraint exists or otherwise can be explicitly checked.

GLOBAL_CONSTRAINT = None

Global constraints

INVALID_VALUES = None

Attribute values that indicate the attribute is not specified.

asn_name

Suggest filename for the association

asn_rule

Name of the rule

ioregistry = {'json': <class 'jwst.associations.association_io.json'>, 'yaml': <class 'jwst.associations.association_io.yaml'>}

The association IO registry

is_valid

Check if association is valid

registry = None

Registry this rule has been placed in.

Methods Documentation

add(item, check_constraints=True)

Add the item to the association

Parameters:

• item (dict) – The item to add.

• check_constraints (bool) – If True, see if the item should belong to this association. If False, just add it.

Returns:

2-tuple consisting of:

• bool : True if match

• [ProcessList[, …]]: List of items to process again.

Return type:

(match, reprocess_list)

check_and_set_constraints(item)

Check whether the given dictionaries match parameters for for this association

Parameters:

item (dict) – The parameters to check/set for this association. This can be a list of dictionaries.

Returns:

2-tuple consisting of:

• bool : Did constraint match?

• [ProcessItem[, …]]: List of items to process again.

Return type:

(match, reprocess)

classmethod create(item, version_id=None)

Create association if item belongs

Parameters:

• item (dict) – The item to initialize the association with.

• version_id (str or None) – Version ID to use in the name of this association. If None, nothing is added.

Returns:

2-tuple consisting of:

• association or None: The association or, if the item does not match this rule, None

• [ProcessList[, …]]: List of items to process again.

Return type:

(association, reprocess_list)

dump(format='json', **kwargs)

Serialize the association

Parameters:

• format (str) – The format to use to dump the association into.

• kwargs (dict) – List of arguments to pass to the registered routines for the current association type.

Returns:

Tuple where the first item is the suggested base name for the file. Second item is the serialization.

Return type:

(name, serialized)

Raises:

• AssociationError – If the operation cannot be done

• AssociationNotValidError – If the given association does not validate.

finalize()

Finalize association

Finalize or close-off this association. Perform validations, modifications, etc. to ensure that the association is complete.

Returns:

associations – List of fully-qualified associations that this association represents. None if a complete association cannot be produced.

Return type:

[association[, …]] or None

is_item_member(item)

Check if item is already a member of this association

Parameters:

item (dict) – The item to add.

Returns:

is_item_member – True if item is a member.

Return type:

bool

items() → a set-like object providing a view on D's items

keys() → a set-like object providing a view on D's keys

classmethod load(serialized, format=None, validate=True, **kwargs)

Marshall a previously serialized association

Parameters:

• serialized (object) – The serialized form of the association.

• format (str or None) – The format to force. If None, try all available.

• validate (bool) – Validate against the class’ defined schema, if any.

• kwargs (dict) – Other arguments to pass to the load method

Returns:

association – The association.

Return type:

Association

Raises:

AssociationNotValidError – Cannot create or validate the association.

Notes

The serialized object can be in any format supported by the registered I/O routines. For example, for json and yaml formats, the input can be either a string or a file object containing the string.

match_constraint(item, constraint, conditions)

Generic constraint checking

Parameters:

• item (dict) – The item to retrieve the values from

• constraint (str) – The name of the constraint

• conditions (dict) – The conditions structure

Returns:

2-tuple consisting of:

• bool : True if the all constraints are satisfied

• [ProcessList[, …]]: List of items to process again.

Return type:

(matches, reprocess_list)

classmethod validate(asn)

Validate an association against this rule

Parameters:

asn (Association or association-like) – The association structure to examine

Returns:

valid – True if valid. Otherwise the AssociationNotValidError is raised

Return type:

bool

Raises:

AssociationNotValidError – If there is some reason validation failed.

Notes

The base method checks against the rule class’ schema If the rule class does not define a schema, a warning is issued but the routine will return True.

values() → an object providing a view on D's values