import json
from types import SimpleNamespace
from typing import Any, Dict, Optional, Sequence
import requests
# Query to find OWL datatype properties
DTPROP_QUERY = """
SELECT DISTINCT ?elem
WHERE {
?elem a owl:DatatypeProperty .
}
"""
# Query to find OWL object properties
OPROP_QUERY = """
SELECT DISTINCT ?elem
WHERE {
?elem a owl:ObjectProperty .
}
"""
ELEM_TYPES = {
"classes": None,
"rels": None,
"dtprops": DTPROP_QUERY,
"oprops": OPROP_QUERY,
}
[docs]
class NeptuneRdfGraph:
"""Neptune wrapper for RDF graph operations.
Args:
host: endpoint for the database instance
port: port number for the database instance, default is 8182
use_iam_auth: boolean indicating IAM auth is enabled in Neptune cluster
use_https: whether to use secure connection, default is True
client: optional boto3 Neptune client
credentials_profile_name: optional AWS profile name
region_name: optional AWS region, e.g., us-west-2
service: optional service name, default is neptunedata
sign: optional, whether to sign the request payload, default is True
Example:
.. code-block:: python
graph = NeptuneRdfGraph(
host='<SPARQL host'>,
port=<SPARQL port>
)
schema = graph.get_schema()
OR
graph = NeptuneRdfGraph(
host='<SPARQL host'>,
port=<SPARQL port>
)
schema_elem = graph.get_schema_elements()
#... change schema_elements ...
graph.load_schema(schema_elem)
*Security note*: Make sure that the database connection uses credentials
that are narrowly-scoped to only include necessary permissions.
Failure to do so may result in data corruption or loss, since the calling
code may attempt commands that would result in deletion, mutation
of data if appropriately prompted or reading sensitive data if such
data is present in the database.
The best way to guard against such negative outcomes is to (as appropriate)
limit the permissions granted to the credentials used with this tool.
See https://python.langchain.com/docs/security for more information.
"""
[docs]
def __init__(
self,
host: str,
port: int = 8182,
use_https: bool = True,
use_iam_auth: bool = False,
client: Any = None,
credentials_profile_name: Optional[str] = None,
region_name: Optional[str] = None,
service: str = "neptunedata",
sign: bool = True,
) -> None:
self.use_iam_auth = use_iam_auth
self.region_name = region_name
self.query_endpoint = f"https://{host}:{port}/sparql"
try:
if client is not None:
self.client = client
else:
import boto3
if credentials_profile_name is not None:
self.session = boto3.Session(profile_name=credentials_profile_name)
else:
# use default credentials
self.session = boto3.Session()
client_params = {}
if region_name:
client_params["region_name"] = region_name
protocol = "https" if use_https else "http"
client_params["endpoint_url"] = f"{protocol}://{host}:{port}"
if sign:
self.client = self.session.client(service, **client_params)
else:
from botocore import UNSIGNED
from botocore.config import Config
self.client = self.session.client(
service,
**client_params,
config=Config(signature_version=UNSIGNED),
)
except ImportError:
raise ModuleNotFoundError(
"Could not import boto3 python package. "
"Please install it with `pip install boto3`."
)
except Exception as e:
if type(e).__name__ == "UnknownServiceError":
raise ModuleNotFoundError(
"NeptuneGraph requires a boto3 version 1.28.38 or greater."
"Please install it with `pip install -U boto3`."
) from e
else:
raise ValueError(
"Could not load credentials to authenticate with AWS client. "
"Please check that credentials in the specified "
"profile name are valid."
) from e
# Set schema
self.schema = ""
self.schema_elements: Dict[str, Any] = {}
self._refresh_schema()
@property
def get_schema(self) -> str:
"""
Returns the schema of the graph database.
"""
return self.schema
@property
def get_schema_elements(self) -> Dict[str, Any]:
return self.schema_elements
[docs]
def get_summary(self) -> Dict[str, Any]:
"""
Obtain Neptune statistical summary of classes and predicates in the graph.
"""
return self.client.get_rdf_graph_summary(mode="detailed")
[docs]
def query(
self,
query: str,
) -> Dict[str, Any]:
"""
Run Neptune query.
"""
request_data = {"query": query}
data = request_data
request_hdr = None
if self.use_iam_auth:
credentials = self.session.get_credentials()
credentials = credentials.get_frozen_credentials()
access_key = credentials.access_key
secret_key = credentials.secret_key
service = "neptune-db"
session_token = credentials.token
params = None
creds = SimpleNamespace(
access_key=access_key,
secret_key=secret_key,
token=session_token,
region=self.region_name,
)
from botocore.awsrequest import AWSRequest
request = AWSRequest(
method="POST", url=self.query_endpoint, data=data, params=params
)
from botocore.auth import SigV4Auth
SigV4Auth(creds, service, self.region_name).add_auth(request)
request.headers["Content-Type"] = "application/x-www-form-urlencoded"
request_hdr = request.headers
else:
request_hdr = {}
request_hdr["Content-Type"] = "application/x-www-form-urlencoded"
queryres = requests.request(
method="POST", url=self.query_endpoint, headers=request_hdr, data=data
)
json_resp = json.loads(queryres.text)
return json_resp
[docs]
def load_schema(self, schema_elements: Dict[str, Any]) -> None:
"""
Generates and sets schema from schema_elements. Helpful in
cases where introspected schema needs pruning.
"""
elem_str = {}
for elem in ELEM_TYPES:
res_list = []
for elem_rec in schema_elements[elem]:
uri = elem_rec["uri"]
local = elem_rec["local"]
res_str = f"<{uri}> ({local})"
res_list.append(res_str)
elem_str[elem] = ", ".join(res_list)
self.schema = (
"In the following, each IRI is followed by the local name and "
"optionally its description in parentheses. \n"
"The graph supports the following node types:\n"
f"{elem_str['classes']}\n"
"The graph supports the following relationships:\n"
f"{elem_str['rels']}\n"
"The graph supports the following OWL object properties:\n"
f"{elem_str['dtprops']}\n"
"The graph supports the following OWL data properties:\n"
f"{elem_str['oprops']}"
)
def _get_local_name(self, iri: str) -> Sequence[str]:
"""
Split IRI into prefix and local
"""
if "#" in iri:
tokens = iri.split("#")
return [f"{tokens[0]}#", tokens[-1]]
elif "/" in iri:
tokens = iri.split("/")
return [f"{'/'.join(tokens[0:len(tokens)-1])}/", tokens[-1]]
else:
raise ValueError(f"Unexpected IRI '{iri}', contains neither '#' nor '/'.")
def _refresh_schema(self) -> None:
"""
Query Neptune to introspect schema.
"""
self.schema_elements["distinct_prefixes"] = {}
# get summary and build list of classes and rels
summary = self.get_summary()
reslist = []
for c in summary["payload"]["graphSummary"]["classes"]:
uri = c
tokens = self._get_local_name(uri)
elem_record = {"uri": uri, "local": tokens[1]}
reslist.append(elem_record)
if tokens[0] not in self.schema_elements["distinct_prefixes"]:
self.schema_elements["distinct_prefixes"][tokens[0]] = "y"
self.schema_elements["classes"] = reslist
reslist = []
for r in summary["payload"]["graphSummary"]["predicates"]:
for p in r:
uri = p
tokens = self._get_local_name(uri)
elem_record = {"uri": uri, "local": tokens[1]}
reslist.append(elem_record)
if tokens[0] not in self.schema_elements["distinct_prefixes"]:
self.schema_elements["distinct_prefixes"][tokens[0]] = "y"
self.schema_elements["rels"] = reslist
# get dtprops and oprops too
for elem in ELEM_TYPES:
q = ELEM_TYPES.get(elem)
if not q:
continue
items = self.query(q)
reslist = []
for r in items["results"]["bindings"]:
uri = r["elem"]["value"]
tokens = self._get_local_name(uri)
elem_record = {"uri": uri, "local": tokens[1]}
reslist.append(elem_record)
if tokens[0] not in self.schema_elements["distinct_prefixes"]:
self.schema_elements["distinct_prefixes"][tokens[0]] = "y"
self.schema_elements[elem] = reslist
self.load_schema(self.schema_elements)
