[#1] Add method get_private_key_from_wif

Signed-off-by: ilyas585 <niyazov2023@gmail.com>

frostfs_api/crypto/key_extension.py

@@ -0,0 +1,11 @@
+import base58
+
+
+class KeyExtension:
+    def get_private_key_from_wif(self, wif: str):
+        decoded = base58.b58decode_check(wif)
+        if len(decoded) != 34 or decoded[0] != 0x80 or decoded[-1] != 0x01:
+            raise ValueError("Incorrect WIF private key")
+
+        private_key = decoded[1:-1]
+        return private_key

requirements.txt

@@ -0,0 +1,3 @@
+base58==2.1.1
+ecdsa==0.19.0
+pytest==8.3.4

tests/conftest.py

@@ -0,0 +1,20 @@
+import pytest
+
+from frostfs_api.crypto.key_extension import KeyExtension
+from frostfs_api.client.verifier import Verifier
+from frostfs_api.client.signer import Signer
+
+
+@pytest.fixture(scope="session")
+def client_key_extension():
+    return KeyExtension()
+
+
+@pytest.fixture(scope="session")
+def client_signer():
+    return Signer()
+
+
+@pytest.fixture(scope="session")
+def client_verifier():
+    return Verifier()

tests/crypto/test_key_extension.py

@@ -0,0 +1,16 @@
+from frostfs_api.crypto.key_extension import KeyExtension
+from tests.helpers.convert import convert_bytes_format_127_to_256
+
+
+class TestKeyExtension:
+    WIF = "L1YS4myg3xHPvi3FHeLaEt7G8upwJaWL5YLV7huviuUtXFpzBMqZ"
+    PRIVATE_KEY = [
+        -128, -5, 30, -36, -118, 85, -67, -6, 81, 43, 93, -38, 106, 21, -88, 127, 15, 125, -79, -17, -40, 77, -15,
+        122, -88, 72, 109, -47, 125, -80, -40, -38
+    ]
+
+    def test_get_private_key_from_wif_success(self, client_key_extension: KeyExtension):
+        private_key = client_key_extension.get_private_key_from_wif(self.WIF)
+
+        assert len(private_key) == 32, f"Not correct len of private key, expected: 32 Actual: {len(private_key)} "
+        assert private_key == bytes(convert_bytes_format_127_to_256(self.PRIVATE_KEY)), f"Not match private key, Expected: {self.PRIVATE_KEY}, Actual: {private_key}"

tests/helpers/convert.py

@@ -0,0 +1,18 @@
+def convert_bytes_format_127_to_256(numbers: list[int]):
+    new_list = []
+    for num in numbers:
+        if num > 0:
+            new_list.append(num)
+        else:
+            new_list.append(num + 256)
+    return new_list
+
+
+def convert_bytes_format_256_to_127(numbers: list[int]):
+    new_list = []
+    for num in numbers:
+        if num < 128:
+            new_list.append(num)
+        else:
+            new_list.append(num - 256)
+    return new_list