refactor(framework) Extend function to get sha256 for integers (#4747)

src/py/flwr/cli/utils.py

@@ -22,7 +22,7 @@
 from contextlib import contextmanager
 from logging import DEBUG
 from pathlib import Path
-from typing import Any, Callable, Optional, cast
+from typing import Any, Callable, Optional, Union, cast
 
 import grpc
 import typer
@@ -148,15 +148,18 @@ def sanitize_project_name(name: str) -> str:
     return sanitized_name
 
 
-def get_sha256_hash(file_path: Path) -> str:
+def get_sha256_hash(file_path_or_int: Union[Path, int]) -> str:
     """Calculate the SHA-256 hash of a file."""
     sha256 = hashlib.sha256()
-    with open(file_path, "rb") as f:
-        while True:
-            data = f.read(65536)  # Read in 64kB blocks
-            if not data:
-                break
-            sha256.update(data)
+    if isinstance(file_path_or_int, Path):
+        with open(file_path_or_int, "rb") as f:
+            while True:
+                data = f.read(65536)  # Read in 64kB blocks
+                if not data:
+                    break
+                sha256.update(data)
+    elif isinstance(file_path_or_int, int):
+        sha256.update(str(file_path_or_int).encode())
     return sha256.hexdigest()
 
 

src/py/flwr/cli/utils_test.py

@@ -0,0 +1,109 @@
+# Copyright 2024 Flower Labs GmbH. 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.
+# ==============================================================================
+"""Test for Flower command line interface utils."""
+
+
+import hashlib
+import os
+import tempfile
+import unittest
+from pathlib import Path
+
+from flwr.cli.utils import get_sha256_hash
+
+
+class TestGetSHA256Hash(unittest.TestCase):
+    """Unit tests for `get_sha256_hash` function."""
+
+    def test_hash_with_integer(self) -> None:
+        """Test the SHA-256 hash calculation when input is an integer."""
+        # Prepare
+        test_int = 13413
+        expected_hash = hashlib.sha256(str(test_int).encode()).hexdigest()
+
+        # Execute
+        result = get_sha256_hash(test_int)
+
+        # Assert
+        self.assertEqual(result, expected_hash)
+
+    def test_hash_with_file(self) -> None:
+        """Test the SHA-256 hash calculation when input is a file path."""
+        # Prepare - Create a temporary file with known content
+        with tempfile.NamedTemporaryFile(delete=False) as temp_file:
+            temp_file.write(b"Test content for SHA-256 hashing.")
+            temp_file_path = Path(temp_file.name)
+
+        try:
+            # Execute
+            sha256 = hashlib.sha256()
+            with open(temp_file_path, "rb") as f:
+                while True:
+                    data = f.read(65536)
+                    if not data:
+                        break
+                    sha256.update(data)
+            expected_hash = sha256.hexdigest()
+
+            result = get_sha256_hash(temp_file_path)
+
+            # Assert
+            self.assertEqual(result, expected_hash)
+        finally:
+            # Clean up the temporary file
+            os.remove(temp_file_path)
+
+    def test_empty_file(self) -> None:
+        """Test the SHA-256 hash calculation for an empty file."""
+        # Prepare
+        with tempfile.NamedTemporaryFile(delete=False) as temp_file:
+            temp_file_path = Path(temp_file.name)
+
+        try:
+            # Execute
+            expected_hash = hashlib.sha256(b"").hexdigest()
+            result = get_sha256_hash(temp_file_path)
+
+            # Assert
+            self.assertEqual(result, expected_hash)
+        finally:
+            os.remove(temp_file_path)
+
+    def test_large_file(self) -> None:
+        """Test the SHA-256 hash calculation for a large file."""
+        # Prepare - Generate large data (e.g., 10 MB)
+        large_data = b"a" * (10 * 1024 * 1024)  # 10 MB of 'a's
+        with tempfile.NamedTemporaryFile(delete=False) as temp_file:
+            temp_file.write(large_data)
+            temp_file_path = Path(temp_file.name)
+
+        try:
+            expected_hash = hashlib.sha256(large_data).hexdigest()
+            # Execute
+            result = get_sha256_hash(temp_file_path)
+
+            # Assert
+            self.assertEqual(result, expected_hash)
+        finally:
+            os.remove(temp_file_path)
+
+    def test_nonexistent_file(self) -> None:
+        """Test the SHA-256 hash calculation when the file does not exist."""
+        # Prepare
+        nonexistent_path = Path("/path/to/nonexistent/file.txt")
+
+        # Execute & assert
+        with self.assertRaises(FileNotFoundError):
+            get_sha256_hash(nonexistent_path)