# Copyright (c) 2023, NVIDIA CORPORATION. All rights reserved.
#
# 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 typing import List
# version>= 1.0.3
import private_set_intersection.python as psi
[docs]
class PSIClient:
"""
Class to represent the psi Client in a two-party client, server PSI model.
"""
def __init__(self, items: List[str]):
"""
Args:
items: the items provided by the client
"""
if len(items) == 0:
raise RuntimeError("Client items cannot be empty")
self.reveal_intersection = True
self.psi_client = psi.client.CreateWithNewKey(self.reveal_intersection)
self.items = items
self.setup = None
[docs]
def get_items_size(self) -> int:
return len(self.items)
[docs]
def receive_setup(self, setup_msg: str):
"""
Args:
setup_msg: serialized setup str
"""
s_setup_sub = psi.ServerSetup()
s_setup_sub.ParseFromString(setup_msg)
self.setup = s_setup_sub
[docs]
def get_request(self, items):
self.items = items
request = self.psi_client.CreateRequest(items).SerializeToString()
return request
[docs]
def get_intersection(self, server_response_msg: str) -> List[str]:
"""Returns the intersection of client and server items.
Args: server_response_msg (PsiProtoResponse): The server response serialized string
Returns:
The intersection set (List[str]) of client and server items
"""
resp_sub = psi.Response()
resp_sub.ParseFromString(server_response_msg)
response = resp_sub
client_item_indices = sorted(self.psi_client.GetIntersection(self.setup, response))
item_size = self.get_items_size()
# if the index is out of client item range, simply ignore.
return [self.items[i] for i in client_item_indices if i < item_size]