"""
This module provides the KGQuery class, which represents one or more
KGObjects identified by a range of possible types and by some of their
metadata, but whose specific identifier(s) is/are not known.
"""
# Copyright 2018-2024 CNRS
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import logging
from typing import Dict, List, Optional, Union, Any, TYPE_CHECKING
from openminds.registry import lookup
from .utility import as_list, expand_filter
from .caching import object_cache
from .base import Resolvable
if TYPE_CHECKING:
from .client import KGClient
from .kgobject import KGObject
logger = logging.getLogger("fairgraph")
[docs]
class KGQuery(Resolvable):
"""
Representation of one or more KGObjects identified by a range of possible types
and by some of their metadata, but whose specific identifier(s) is/are not known.
It is possible that no KGObjects match the types/metadata.
Args:
classes (list of KGObject subclasses): a list of types to query.
filter (dict): key:value pairs that should be matched. All pairs must match.
preferred_release_status (str): The preferred scope used to resolve the query.
Valid values are "released", "in progress", or "any".
Example:
>>> import fairgraph.openminds.core as omcore
>>> from fairgraph.utility import as_list
>>> query = KGQuery([omcore.Person], {"family_name": "Amunts"})
>>> people = as_list(query.resolve(kg_client))
>>> len(people)
1
>>> people[0].family_name
Amunts
"""
def __init__(
self,
classes: Union[str, KGObject, List[Union[str, KGObject]]],
filter: Dict[str, str],
preferred_release_status: str = "released",
):
self.classes: List[KGObject] = []
for cls in as_list(classes):
if isinstance(cls, str):
resolved_cls = lookup(cls)
assert isinstance(resolved_cls, KGObject)
self.classes.append(resolved_cls)
else:
self.classes.append(cls)
self.filter = filter
self.preferred_release_status = preferred_release_status
def __repr__(self):
return f"""{self.__class__.__name__}([{", ".join(cls.__name__ for cls in self.classes)}], filter="{self.filter!r}")""".replace(
"https://kg.ebrains.eu/api/instances/", ""
)
[docs]
def resolve(
self,
client: KGClient,
size: int = 10000,
from_index: int = 0,
space: Optional[str] = None,
release_status: Optional[str] = None,
use_cache: bool = True,
follow_links: Optional[Dict[str, Any]] = None,
with_reverse_properties: Optional[bool] = False,
):
"""
Retrieve the full metadata for the KGObject(s) represented by this query object.
Args:
client: a KGClient
from_index: The index of the first result to include in the response.
size: The maximum number of results to include in the response.
space: If specified, queries only in the given space.
release_status (str, optional): The scope of the query. Valid values are "released", "in progress", or "any".
If not provided, the "preferred_release_status" provided when creating the proxy object will be used.
use_cache (bool): Whether to use cached data if they exist. Defaults to True.
follow_links (dict): The links in the graph to follow. Defaults to None.
with_reverse_properties (dict): Whether to include reverse properties. Defaults to False.
Returns:
a KGObject instance, of the appropriate subclass.
"""
release_status = release_status or self.preferred_release_status
objects: List[KGObject] = []
for cls in self.classes:
if hasattr(cls, "generate_query"):
# if cls is EmbeddedMetadata we cannot query it
query = cls.generate_query(
client=client,
filters=self.filter,
space=space,
follow_links=follow_links,
with_reverse_properties=with_reverse_properties,
)
instances = client.query(
query=query,
size=size,
from_index=from_index,
release_status=release_status,
).data
objects.extend(cls.from_jsonld(instance_data, client) for instance_data in instances)
for obj in objects:
object_cache[obj.id] = obj
if follow_links:
for obj in objects:
obj.resolve(client, release_status=release_status, use_cache=use_cache, follow_links=follow_links)
if len(objects) == 1:
return objects[0]
else:
return objects
[docs]
def count(self, client: KGClient, space: Optional[str] = None, release_status: Optional[str] = None):
"""
Return the number of objects that would be returned by resolving this query.
"""
release_status = release_status or self.preferred_release_status
n = 0
for cls in self.classes:
n += cls.count(client, api="query", release_status=release_status, space=space, **self.filter)
return n
