def compatibility_numerical(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
# https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.2
result = SchemaCompatibilityResult.compatible()
reader_type = get_type_of(reader_schema)
writer_type = get_type_of(writer_schema)
reader_is_number = reader_type in (Instance.NUMBER, Instance.INTEGER)
writer_is_number = writer_type in (Instance.NUMBER, Instance.INTEGER)
assert reader_is_number, "types should have been previously checked"
assert writer_is_number, "types should have been previously checked"
checks: List[AssertionCheck] = [MAXIMUM_CHECK, MINIMUM_CHECK, EXCLUSIVE_MAXIMUM_CHECK, EXCLUSIVE_MINIMUM_CHECK]
for assertion_check in checks:
check_result = check_assertion_compatibility(
reader_schema,
writer_schema,
assertion_check,
location,
)
result = result.merged_with(check_result)
reader_multiple = reader_schema.get(Keyword.MULTIPLE.value)
writer_multiple = writer_schema.get(Keyword.MULTIPLE.value)
if introduced_constraint(reader_multiple, writer_multiple):
result.add_incompatibility(
incompat_type=Incompatibility.multiple_added,
message=INTRODUCED_INCOMPATIBILITY_MSG_FMT.format(
assert_name=Keyword.MULTIPLE.value, introduced_value=writer_multiple
),
location=location,
)
if ne(reader_multiple, writer_multiple):
if reader_multiple > writer_multiple:
message_expanded = f"Multiple must not increase ({reader_multiple} > {writer_multiple})"
result.add_incompatibility(
incompat_type=Incompatibility.multiple_expanded, message=message_expanded, location=location
)
elif writer_multiple % reader_multiple != 0:
message_changed = (
f"{reader_multiple} must be an integer multiple of "
f"{writer_multiple} ({writer_multiple} % {reader_multiple} = 0)"
)
result.add_incompatibility(
incompat_type=Incompatibility.multiple_changed, message=message_changed, location=location
)
if reader_type == Instance.INTEGER and writer_type == Instance.NUMBER:
message_narrowed = "Writer produces numbers while reader only accepted integers"
result.add_incompatibility(incompat_type=Incompatibility.type_narrowed, message=message_narrowed, location=location)
return result
def compatibility_string(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
# https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.3
result = SchemaCompatibilityResult.compatible()
assert get_type_of(reader_schema) == Instance.STRING, "types should have been previously checked"
assert get_type_of(writer_schema) == Instance.STRING, "types should have been previously checked"
checks: List[AssertionCheck] = [MAX_LENGTH_CHECK, MIN_LENGTH_CHECK, PATTERN_CHECK]
for assertion_check in checks:
check_result = check_assertion_compatibility(
reader_schema,
writer_schema,
assertion_check,
location,
)
result = result.merged_with(check_result)
return result
def compatibility_boolean_schema(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
assert get_type_of(reader_schema) is BooleanSchema, "types should have been previously checked"
assert get_type_of(writer_schema) is BooleanSchema, "types should have been previously checked"
# The true schema accepts everything, so the writer can produce anything
if is_true_schema(reader_schema):
return SchemaCompatibilityResult.compatible()
# The false schema is only compatible with itself
if is_false_schema(writer_schema):
return SchemaCompatibilityResult.compatible()
reader_has_not = isinstance(reader_schema, dict) and Subschema.NOT.value in reader_schema
location_not = location + [Subschema.NOT.value]
return SchemaCompatibilityResult.incompatible(
incompat_type=Incompatibility.type_changed,
message=f"All new values are rejected by {reader_schema}",
location=location_not if reader_has_not else location,
)
def compatibility_subschemas(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
# https://json-schema.org/draft/2020-12/json-schema-core.html#rfc.section.10
# pylint: disable=too-many-return-statements
reader_subschemas_and_type = maybe_get_subschemas_and_type(reader_schema)
writer_subschemas_and_type = maybe_get_subschemas_and_type(writer_schema)
reader_subschemas: Optional[List[Any]]
reader_type: JSONSCHEMA_TYPES
if reader_subschemas_and_type is not None:
reader_subschemas = reader_subschemas_and_type[0]
reader_type = reader_subschemas_and_type[1]
reader_has_subschema = reader_type in (Subschema.ALL_OF, Subschema.ANY_OF, Subschema.ONE_OF)
else:
reader_subschemas = None
reader_type = get_type_of(reader_schema)
reader_has_subschema = False
writer_subschemas: Optional[List[Any]]
writer_type: JSONSCHEMA_TYPES
if writer_subschemas_and_type is not None:
writer_subschemas = writer_subschemas_and_type[0]
writer_type = writer_subschemas_and_type[1]
writer_has_subschema = writer_type in (Subschema.ALL_OF, Subschema.ANY_OF, Subschema.ONE_OF)
else:
writer_subschemas = None
writer_type = get_type_of(writer_schema)
writer_has_subschema = False
is_reader_special_case = reader_has_subschema and not writer_has_subschema and is_simple_subschema(reader_schema)
is_writer_special_case = not reader_has_subschema and writer_has_subschema and is_simple_subschema(writer_schema)
subschema_location = location + [get_name_of(reader_type)]
if is_reader_special_case:
assert reader_subschemas
return check_simple_subschema(reader_subschemas[0], writer_schema, reader_type, writer_type, subschema_location)
if is_writer_special_case:
assert writer_subschemas
return check_simple_subschema(reader_schema, writer_subschemas[0], reader_type, writer_type, subschema_location)
if reader_type in (Subschema.ANY_OF, Subschema.ONE_OF) and not writer_has_subschema:
assert isinstance(reader_type, Subschema)
for reader_subschema in reader_schema[reader_type.value]:
rec_result = compatibility_rec(reader_subschema, writer_schema, subschema_location)
if is_compatible(rec_result):
return rec_result
return type_mismatch(reader_type, writer_type, subschema_location)
if reader_subschemas is not None and writer_subschemas is not None:
if reader_type not in (Subschema.ANY_OF, writer_type):
return SchemaCompatibilityResult.incompatible(
Incompatibility.combined_type_changed,
message=f"incompatible subschema change, from {reader_type} to {writer_type}",
location=subschema_location,
)
len_reader_subschemas = len(reader_subschemas)
len_writer_subschemas = len(writer_subschemas)
if reader_type == Subschema.ALL_OF and len_writer_subschemas < len_reader_subschemas:
msg = (
f"Not all required schemas were provided, number of required "
f"schemas increased from {len_writer_subschemas} to "
f"{len_reader_subschemas}"
)
return SchemaCompatibilityResult.incompatible(
Incompatibility.product_type_extended,
message=msg,
location=subschema_location,
)
# oneOf/anyOf differ on annotation collection not validation.
if reader_type in (Subschema.ANY_OF, Subschema.ONE_OF) and len_writer_subschemas > len_reader_subschemas:
msg = (
f"Not all schemas are accepted, number of schemas "
f"reduced from {len_writer_subschemas} to "
f"{len_reader_subschemas}"
)
return SchemaCompatibilityResult.incompatible(
Incompatibility.sum_type_narrowed,
message=msg,
location=subschema_location,
)
if reader_type == Subschema.ALL_OF:
qty_of_required_compatible_subschemas = len_reader_subschemas
else:
qty_of_required_compatible_subschemas = len_writer_subschemas
compatible_schemas_count = count_uniquely_compatible_schemas(
reader_type,
reader_subschemas,
writer_subschemas,
subschema_location,
)
if compatible_schemas_count < qty_of_required_compatible_subschemas:
return SchemaCompatibilityResult.incompatible(
Incompatibility.combined_type_subschemas_changed,
message="subschemas are incompatible",
location=subschema_location,
)
return SchemaCompatibilityResult.compatible()
return type_mismatch(reader_type, writer_type, subschema_location)
def compatibility_object(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
# https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.5
result = SchemaCompatibilityResult.compatible()
assert get_type_of(reader_schema) == Instance.OBJECT, "types should have been previously checked"
assert get_type_of(writer_schema) == Instance.OBJECT, "types should have been previously checked"
properties_location = location + [Keyword.PROPERTIES.value]
reader_properties = reader_schema.get(Keyword.PROPERTIES.value)
writer_properties = writer_schema.get(Keyword.PROPERTIES.value)
reader_property_set = set(reader_properties) if reader_properties else set()
writer_property_set = set(writer_properties) if writer_properties else set()
# These properties are unknown in the sense they don't have a direct
# schema, however there may be an indirect schema (patternProperties or
# additionalProperties)
properties_unknown_to_writer = reader_property_set - writer_property_set
properties_unknown_to_reader = writer_property_set - reader_property_set
for common_property in reader_property_set & writer_property_set:
this_property_location = properties_location + [common_property]
reader_property = reader_properties[common_property]
writer_property = writer_properties[common_property]
is_required_by_reader = reader_property.get(Keyword.REQUIRED.value)
is_required_by_writer = writer_property.get(Keyword.REQUIRED.value)
if not is_required_by_writer and is_required_by_reader:
result.add_incompatibility(
incompat_type=Incompatibility.required_attribute_added,
message=f"Property {common_property} became required",
location=this_property_location,
)
rec_result = compatibility_rec(
reader_schema=reader_property,
writer_schema=writer_property,
location=this_property_location,
)
if is_incompatible(rec_result):
result = result.merged_with(rec_result)
# With an open content model any property can be added without breaking
# compatibility because those do not have assertions, so only check if the
# reader is using a closed model
if properties_unknown_to_reader and not is_object_content_model_open(reader_schema):
for unknown_property_to_reader in properties_unknown_to_reader:
schema_for_property = schema_from_partially_open_content_model(reader_schema, unknown_property_to_reader)
if schema_for_property is None:
result.add_incompatibility(
incompat_type=Incompatibility.property_removed_from_closed_content_model,
message=f"The property {unknown_property_to_reader} is not accepted anymore",
location=properties_location,
)
else:
rec_result = compatibility_rec(
reader_schema=schema_for_property,
writer_schema=writer_properties[unknown_property_to_reader],
location=properties_location,
)
if is_incompatible(rec_result):
result = result.merged_with(rec_result)
result.add_incompatibility(
incompat_type=Incompatibility.property_removed_not_covered_by_partially_open_content_model,
message=f"property {unknown_property_to_reader} is not compatible",
location=properties_location,
)
elif properties_unknown_to_writer:
is_writer_open_model = is_object_content_model_open(writer_schema)
if is_writer_open_model:
properties = ', '.join(properties_unknown_to_writer)
message_property_added_to_open_content_model = (
f"Restricting acceptable values of properties is an incompatible "
f"change. The following properties {properties} accepted any "
f"value because of the lack of validation (the object schema had "
f"neither patternProperties nor additionalProperties), now "
f"these values are restricted."
)
result.add_incompatibility(
incompat_type=Incompatibility.property_added_to_open_content_model,
message=message_property_added_to_open_content_model,
location=properties_location
)
if not is_writer_open_model:
for unknown_property_to_writer in properties_unknown_to_writer:
schema_for_property = schema_from_partially_open_content_model(writer_schema, unknown_property_to_writer)
schema_for_property_exists = schema_for_property is not None
schema_allows_writes = not is_false_schema(schema_for_property)
if schema_for_property_exists and schema_allows_writes:
rec_result = compatibility_rec(
reader_schema=reader_properties[unknown_property_to_writer],
writer_schema=schema_for_property,
location=properties_location,
)
if is_incompatible(rec_result):
result.add_incompatibility(
incompat_type=Incompatibility.property_added_not_covered_by_partially_open_content_model,
message="incompatible schemas",
location=properties_location,
)
new_property_is_required_without_default = (
unknown_property_to_writer in reader_schema.get(Keyword.REQUIRED.value, list())
and Keyword.DEFAULT.value not in reader_properties.get(Keyword.REQUIRED.value, list())
)
if new_property_is_required_without_default:
result.add_incompatibility(
incompat_type=Incompatibility.required_property_added_to_unopen_content_model,
message=f"Property {unknown_property_to_writer} added without a default",
location=properties_location,
)
reader_attribute_dependencies_schema = reader_schema.get(Keyword.DEPENDENCIES.value, dict())
writer_attribute_dependencies_schema = writer_schema.get(Keyword.DEPENDENCIES.value, dict())
for writer_attribute_dependency_name, writer_attribute_dependencies in writer_attribute_dependencies_schema.items():
reader_attribute_dependencies = reader_attribute_dependencies_schema.get(writer_attribute_dependency_name)
if not reader_attribute_dependencies:
result.add_incompatibility(
incompat_type=Incompatibility.dependency_array_added,
message="incompatible dependency array",
location=location,
)
new_dependencies = set(writer_attribute_dependencies) - set(reader_attribute_dependencies)
if new_dependencies:
result.add_incompatibility(
incompat_type=Incompatibility.dependency_array_extended,
message=f"new dependencies {new_dependencies}",
location=location
)
reader_dependent_schemas = reader_schema.get(Keyword.DEPENDENT_SCHEMAS.value, dict())
writer_dependent_schemas = writer_schema.get(Keyword.DEPENDENT_SCHEMAS.value, dict())
for writer_dependent_schema_name, writer_dependent_schema in writer_dependent_schemas.items():
reader_dependent_schema = reader_dependent_schemas.get(writer_dependent_schema_name)
if introduced_constraint(reader_dependent_schema, writer_dependent_schemas):
result.add_incompatibility(
incompat_type=Incompatibility.dependency_schema_added,
message=f"new dependency schema {writer_dependent_schema_name}",
location=location
)
rec_result = compatibility_rec(reader_dependent_schema, writer_dependent_schema, location)
result = result.merged_with(rec_result)
checks: List[AssertionCheck] = [MAX_PROPERTIES_CHECK, MIN_PROPERTIES_CHECK]
for assertion_check in checks:
check_result = check_assertion_compatibility(
reader_schema,
writer_schema,
assertion_check,
location,
)
result = result.merged_with(check_result)
reader_additional_properties = reader_schema.get(Keyword.ADDITIONAL_PROPERTIES.value)
writer_additional_properties = writer_schema.get(Keyword.ADDITIONAL_PROPERTIES.value)
location_additional_properties = location + [Keyword.ADDITIONAL_PROPERTIES.value]
if introduced_constraint(reader_additional_properties, writer_additional_properties):
result.add_incompatibility(
incompat_type=Incompatibility.additional_properties_narrowed,
message="additionalProperties instroduced",
location=location_additional_properties,
)
if reader_additional_properties and writer_additional_properties:
rec_result = compatibility_rec(
reader_additional_properties, writer_additional_properties, location_additional_properties
)
result = result.merged_with(rec_result)
return result
def compatibility_array(reader_schema, writer_schema, location: List[str]) -> SchemaCompatibilityResult:
# https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.4
reader_type = get_type_of(reader_schema)
writer_type = get_type_of(writer_schema)
assert reader_type == Instance.ARRAY, "types should have been previously checked"
assert writer_type == Instance.ARRAY, "types should have been previously checked"
reader_items = reader_schema.get(Keyword.ITEMS.value)
writer_items = writer_schema.get(Keyword.ITEMS.value)
result = SchemaCompatibilityResult.compatible()
reader_is_tuple = is_tuple(reader_schema)
writer_is_tuple = is_tuple(writer_schema)
if reader_is_tuple != writer_is_tuple:
return type_mismatch(reader_type, writer_type, location)
# Extend the array iterator to match the tuple size
if reader_is_tuple and writer_is_tuple:
reader_items_iter = iter(reader_items)
writer_items_iter = iter(writer_items)
reader_requires_more_items = len(reader_items) > len(writer_items)
writer_has_more_items = len(writer_items) > len(reader_items)
else:
reader_items_iter = iter([reader_items])
writer_items_iter = iter([writer_items])
reader_requires_more_items = False
writer_has_more_items = False
pos = 0
for pos, (reader_item, writer_item) in enumerate(zip(reader_items_iter, writer_items_iter), start=pos):
rec_result = compatibility_rec(reader_item, writer_item, location + ["items", f"{pos}"])
if is_incompatible(rec_result):
result = result.merged_with(rec_result)
reader_additional_items = reader_schema.get(Keyword.ADDITIONAL_ITEMS.value, True)
reader_restricts_additional_items = not is_true_schema(reader_additional_items)
location_additional_items = location + [Keyword.ADDITIONAL_ITEMS.value]
if writer_has_more_items and reader_restricts_additional_items:
reader_rejects_additional_items = is_false_schema(reader_restricts_additional_items)
if reader_rejects_additional_items:
result.add_incompatibility(
incompat_type=Incompatibility.item_removed_from_closed_content_model,
message=f"Elements starting from index {pos} are not allowed",
location=location + [Keyword.ADDITIONAL_ITEMS.value],
)
else:
for pos, writer_item in enumerate(writer_items_iter, start=pos):
rec_result = compatibility_rec(reader_restricts_additional_items, writer_item, location_additional_items)
if is_incompatible(rec_result):
result.add_incompatibility(
incompat_type=Incompatibility.item_removed_not_covered_by_partially_open_content_model,
message=f"Item in position {pos} is not compatible",
location=location_additional_items,
)
writer_additional_items = writer_schema.get(Keyword.ADDITIONAL_ITEMS.value, True)
writer_restricts_additional_items = not is_true_schema(writer_additional_items)
if reader_requires_more_items:
# This is just for more detailed diagnostics
if writer_restricts_additional_items:
for pos, reader_item in enumerate(reader_items_iter, start=pos):
location_reader_item = location + ["items", f"{pos}"]
rec_result = compatibility_rec(reader_item, writer_additional_items, location_reader_item)
if is_incompatible(rec_result):
result.add_incompatibility(
incompat_type=Incompatibility.item_added_not_covered_by_partially_open_content_model,
message="New element schema incompatible with the other version",
location=location_reader_item,
)
result.add_incompatibility(
incompat_type=Incompatibility.item_added_to_open_content_model,
message=f"Elements starting from index {pos} are now required",
location=location,
)
if is_tuple_without_additional_items(reader_schema) and not is_tuple_without_additional_items(writer_schema):
result.add_incompatibility(
incompat_type=Incompatibility.additional_items_removed,
message="Additional items are not longer allowed",
location=location_additional_items,
)
reader_additional_items = reader_schema.get(Keyword.ITEMS)
writer_additional_items = writer_schema.get(Keyword.ITEMS)
if introduced_constraint(reader_additional_items, writer_additional_items):
result.add_incompatibility(
incompat_type=Incompatibility.additional_items_removed,
message="Items are now restricted, old values may not be valid anymore",
location=location_additional_items,
)
rec_result = compatibility_rec(reader_additional_items, writer_additional_items, location_additional_items)
result = result.merged_with(rec_result)
checks: List[AssertionCheck] = [MAX_ITEMS_CHECK, MIN_ITEMS_CHECK]
for assertion_check in checks:
check_result = check_assertion_compatibility(
reader_schema,
writer_schema,
assertion_check,
location,
)
result = result.merged_with(check_result)
reader_unique_items = reader_schema.get(Keyword.UNIQUE_ITEMS)
writer_unique_items = reader_schema.get(Keyword.UNIQUE_ITEMS)
if introduced_constraint(reader_unique_items, writer_unique_items):
result.add_incompatibility(
incompat_type=Incompatibility.unique_items_added,
message=INTRODUCED_INCOMPATIBILITY_MSG_FMT.format(
assert_name=Keyword.UNIQUE_ITEMS.value,
introduced_value=writer_unique_items,
),
location=location,
)
return result
def compatibility_rec(
reader_schema: Optional[Any], writer_schema: Optional[Any], location: List[str]
) -> SchemaCompatibilityResult:
if introduced_constraint(reader_schema, writer_schema):
return SchemaCompatibilityResult.incompatible(
incompat_type=Incompatibility.schema_added,
message="schema added, previously used values may not be valid anymore",
location=location,
)
# Note: This is not always an incompatible change, jsonschema accepts
# values unless there is an explicit assertion to reject it, meaning the
# reader_schema would have to be `false` instead of undefined. However, on
# some code paths this is really a incompatible change, specially when the
# reader has type `array` to represent a list, and the writer is either a
# different type or it is also an `array` but now it representes a tuple.
if reader_schema is None and writer_schema is not None:
LOG.debug("Schema removed reader_schema.type='%r'", get_type_of(reader_schema))
return SchemaCompatibilityResult.incompatible(
incompat_type=Incompatibility.schema_removed,
message="schema removed",
location=location,
)
# The type of reader_schema and writer_schema may vary wildly. Example:
#
# reader_schema = {"additionalProperties": {"type": "integer"}, ...}
# writer_schema = {"additionalProperties": false, ...}
#
# When recursing `reader_schema` will be Instance.INTEGER and
# `writer_schema` will be BooleanSchema
#
reader_type = get_type_of(reader_schema)
writer_type = get_type_of(writer_schema)
reader_is_number = reader_type in (Instance.NUMBER, Instance.INTEGER)
writer_is_number = writer_type in (Instance.NUMBER, Instance.INTEGER)
both_are_numbers = reader_is_number and writer_is_number
reader_has_subschema = reader_type in (Subschema.ALL_OF, Subschema.ANY_OF, Subschema.ONE_OF)
writer_has_subschema = writer_type in (Subschema.ALL_OF, Subschema.ANY_OF, Subschema.ONE_OF)
either_has_subschema = reader_has_subschema or writer_has_subschema
reader_is_true_schema = is_true_schema(reader_schema)
reader_is_object = reader_type == Instance.OBJECT
reader_is_true_schema = is_true_schema(reader_schema)
writer_is_object = writer_type == Instance.OBJECT
writer_is_true_schema = is_true_schema(writer_schema)
both_are_object = (reader_is_object or reader_is_true_schema) and (writer_is_object or writer_is_true_schema)
# https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.1.1
if not both_are_numbers and not either_has_subschema and not both_are_object and reader_type != writer_type:
result = type_mismatch(reader_type, writer_type, location)
elif both_are_numbers:
result = compatibility_numerical(reader_schema, writer_schema, location)
elif either_has_subschema:
result = compatibility_subschemas(reader_schema, writer_schema, location)
elif both_are_object:
if reader_is_true_schema:
reader_schema = {"type": Instance.OBJECT.value}
if writer_is_true_schema:
writer_schema = {"type": Instance.OBJECT.value}
result = compatibility_object(reader_schema, writer_schema, location)
elif reader_type is BooleanSchema:
result = SchemaCompatibilityResult.compatible()
elif reader_type is Subschema.NOT:
assert reader_schema, "if just one schema is NOT the result should have been a type_mismatch"
assert writer_schema, "if just one schema is NOT the result should have been a type_mismatch"
location_not = location + [Subschema.NOT.value]
return compatibility_rec(
reader_schema[Subschema.NOT.value],
writer_schema[Subschema.NOT.value],
location_not,
)
elif reader_type == Instance.BOOLEAN:
result = SchemaCompatibilityResult.compatible()
elif reader_type == Instance.STRING:
result = compatibility_string(reader_schema, writer_schema, location)
elif reader_type == Instance.ARRAY:
result = compatibility_array(reader_schema, writer_schema, location)
elif reader_type == Keyword.ENUM:
result = compatibility_enum(reader_schema, writer_schema, location)
elif reader_type is Instance.NULL:
result = SchemaCompatibilityResult.compatible()
else:
raise ValueError(f"unknown type {reader_type}")
return result
