Read ForbiddenRelations clauses from json

[JosuaCarl]

As mentioned in #352, there still is some work to be done on the documentation side of things for ForbiddenRelations. Today I encountered another problem when trying to read in a ConfigurationSpace from a .json file, created with ConfigSpace.

Version: 0.7.1

Error:

"name": "KeyError",
"message": "'name'",
"stack": "---------------------------------------------------------------------------
KeyError Traceback (most recent call last)
Cell In[3], line 20
18 with open('configspace.json', 'r') as f:
19 json_string = f.read()
---> 20 config = cs_json.read(json_string)

File XYZ/.conda/envs/MStoML/lib/python3.11/site-packages/ConfigSpace/read_and_write/json.py:459, in read(jason_string)
450 configuration_space.add_condition(
451 _construct_condition(
452 condition,
453 configuration_space,
454 ),
455 )
457 for forbidden in jason["forbiddens"]:
458 configuration_space.add_forbidden_clause(
--> 459 _construct_forbidden(
460 forbidden,
461 configuration_space,
462 ),
463 )
465 return configuration_space

File XYZ/.conda/envs/MStoML/lib/python3.11/site-packages/ConfigSpace/read_and_write/json.py:668, in _construct_forbidden(clause, cs)
661 forbidden_type = clause["type"]
662 methods = {
663 "EQUALS": _construct_forbidden_equals,
664 "IN": _construct_forbidden_in,
665 "AND": _construct_forbidden_and,
666 "RELATION": _construct_forbidden_equals,
667 }
--> 668 return methods[forbidden_type](clause, cs)

File XYZ/.conda/envs/MStoML/lib/python3.11/site-packages/ConfigSpace/read_and_write/json.py:675, in _construct_forbidden_equals(clause, cs)
671 def _construct_forbidden_equals(
672 clause: dict,
673 cs: ConfigurationSpace,
674 ) -> ForbiddenEqualsClause:
--> 675 return ForbiddenEqualsClause(hyperparameter=cs[clause["name"]], value=clause["value"])

KeyError: 'name'"

Code to reproduce:

ConfigSpace import ConfigurationSpace, Integer, ForbiddenGreaterThanRelation
from ConfigSpace.read_and_write import json as cs_json

configuration_space = ConfigurationSpace(seed=42)
hyperparameters = [
    Integer(        "intermediate_dimension",   (100, 200), log=True, default=200),
    Integer(        "latent_dimension",         (10, 200), log=False, default=50),
]
configuration_space.add_hyperparameters(hyperparameters)
forbidden_clauses = [
    ForbiddenGreaterThanRelation(configuration_space["latent_dimension"], configuration_space["intermediate_dimension"])
]
configuration_space.add_forbidden_clauses(forbidden_clauses)

cs_string = cs_json.write(configuration_space)
with open('configspace.json', 'w') as f:
     f.write(cs_string)

with open('configspace.json', 'r') as f:
    json_string = f.read()
    config = cs_json.read(json_string)

Tracing:
It seems like the following constructor:

ConfigSpace/ConfigSpace/read_and_write/json.py

Lines 705 to 721 in ce27ba2

	def _construct_forbidden_relation( # pyright: ignore
	clause: dict,
	cs: ConfigurationSpace,
	) -> ForbiddenRelation:
	left = cs[clause["left"]]
	right = cs[clause["right"]]
	if clause["lambda"] == "LESS":
	return ForbiddenLessThanRelation(left, right)
	if clause["lambda"] == "EQUALS":
	return ForbiddenEqualsRelation(left, right)
	if clause["lambda"] == "GREATER":
	return ForbiddenGreaterThanRelation(left, right)
	raise ValueError("Unknown relation '%s'" % clause["lambda"])

is never called, which should happen at

ConfigSpace/ConfigSpace/read_and_write/json.py

Line 678 in ce27ba2

"RELATION": _construct_forbidden_equals,

Instead,

ConfigSpace/ConfigSpace/read_and_write/json.py

Lines 683 to 687 in ce27ba2

	def _construct_forbidden_equals(
	clause: dict,
	cs: ConfigurationSpace,
	) -> ForbiddenEqualsClause:
	return ForbiddenEqualsClause(hyperparameter=cs[clause["name"]], value=clause["value"])

is called, which in turn causes the accession attempt of 'name', which is not present in the ForbiddenRelations clause

[JosuaCarl]

Replacing _construct_forbidden_equals with _construct_forbidden_relation in

ConfigSpace/ConfigSpace/read_and_write/json.py

Line 678 in ce27ba2

"RELATION": _construct_forbidden_equals,

fixed my issue.

The bug also seemed to affect the read-in of the Runhistory in SMAC3, when using ForbiddenRelations, this also fixed it for me.

[eddiebergman]

Thanks for the issue and solution!

This has been addressed in #346 which we hope to release next week. I'm not sure when SMAC will udpdate to it as they'll likely want to benchmark that nothing is silently broken. That might take another little bit of time