Source code for nvflare.fuel.hci.base64_utils

# Copyright (c) 2021, 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
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#     http://www.apache.org/licenses/LICENSE-2.0
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# 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
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import base64


[docs]def bytes_to_b64str(data_bytes) -> str: """Convert binary to base64-encoded string.""" encoded_bytes = base64.b64encode(data_bytes) return encoded_bytes.decode("ascii")
[docs]def b64str_to_bytes(b64str: str) -> bytes: """Convert base64-encoded string to binary.""" encoded_bytes = b64str.encode("ascii") return base64.b64decode(encoded_bytes)
[docs]def binary_file_to_b64str(file_name) -> str: """Encode content of a binary file to a Base64-encoded ASCII string. Args: file_name: the binary file to be processed Returns: base64-encoded ASCII string """ data_bytes = open(file_name, "rb").read() return bytes_to_b64str(data_bytes)
[docs]def b64str_to_binary_file(b64str: str, file_name): """Decode a base64-encoded string and write it into a binary file. Args: b64str: the base64-encoded ASCII string file_name: the file to write to Returns: number of bytes written """ data_bytes = b64str_to_bytes(b64str) with open(file_name, "wb") as f: f.write(data_bytes) return len(data_bytes)
[docs]def text_file_to_b64str(file_name) -> str: """Encode content of a text file to a Base64-encoded ASCII string. Args: file_name: name of the text file Returns: base64-encoded string """ data_string = open(file_name, "r").read() data_bytes = data_string.encode("utf-8") return bytes_to_b64str(data_bytes)
[docs]def b64str_to_text_file(b64str: str, file_name): """Decode a base64-encoded string and write result into a text file. Args: b64str: base64-encoded string file_name: file to be created Returns: number of data types written (may not be the same as number of characters) """ data_bytes = b64str_to_bytes(b64str) data_string = data_bytes.decode("utf-8") with open(file_name, "w") as f: f.write(data_string) return len(data_bytes)