From 9c25f8f587b62c90a9142a0a0fb6899d0c9b6240 Mon Sep 17 00:00:00 2001
From: "Antoine R. Dumont (@ardumont)" <antoine.romain.dumont@gmail.com>
Date: Tue, 14 Mar 2017 15:15:06 +0100
Subject: [PATCH] swh.model.hashutil: Open variable length hash algorithm
support
The caveat is that it will only be supported when we will be using
python3 >= 3.5.
Related T692
---
swh/model/hashutil.py | 25 +++++++++++++++---
swh/model/tests/test_hashutil.py | 45 ++++++++++++++++++++++++++++++++
2 files changed, 67 insertions(+), 3 deletions(-)
diff --git a/swh/model/hashutil.py b/swh/model/hashutil.py
index ea28414f..0075e632 100644
--- a/swh/model/hashutil.py
+++ b/swh/model/hashutil.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2015 The Software Heritage developers
+# Copyright (C) 2015-2017 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information
@@ -6,8 +6,10 @@
import binascii
import functools
import hashlib
-from io import BytesIO
import os
+import sys
+
+from io import BytesIO
# supported hashing algorithms
ALGORITHMS = set(['sha1', 'sha256', 'sha1_git'])
@@ -64,7 +66,7 @@ def _new_hash(algo, length=None):
ValueError if algo is unknown, or length is missing for a git-specific
hash.
"""
- if algo not in ALGORITHMS:
+ if algo not in ALGORITHMS and ':' not in algo:
raise ValueError('Unexpected hashing algorithm %s, '
'expected one of %s' %
(algo, ', '.join(sorted(ALGORITHMS))))
@@ -75,6 +77,23 @@ def _new_hash(algo, length=None):
raise ValueError('Missing length for git hashing algorithm')
base_algo = algo[:-4]
h = _new_git_hash(base_algo, 'blob', length)
+ elif ':' in algo: # variable length hashing algorithms (only from
+ # python3 >= 3.6)
+ if sys.version_info.major == 3 and sys.version_info.minor >= 6:
+ _algo = algo.split(':')
+ base_algo = _algo[0]
+ variable_length = int(_algo[1])
+
+ if base_algo == 'blake2b':
+ h = hashlib.blake2b(digest_size=variable_length)
+ elif base_algo == 'blake2s':
+ h = hashlib.blake2s(digest_size=variable_length)
+ else:
+ raise ValueError('Unexpected hashing algorithm %s, '
+ 'expected one of %s' %
+ (algo, ', '.join(sorted(ALGORITHMS))))
+ else:
+ raise ValueError('Unsupported hashing algorithm %s' % algo)
else:
h = hashlib.new(algo)
diff --git a/swh/model/tests/test_hashutil.py b/swh/model/tests/test_hashutil.py
index 614e7ee2..afa5a588 100644
--- a/swh/model/tests/test_hashutil.py
+++ b/swh/model/tests/test_hashutil.py
@@ -8,6 +8,7 @@ import tempfile
import unittest
from nose.tools import istest
+from unittest.mock import MagicMock, patch
from swh.model import hashutil
@@ -124,6 +125,50 @@ class Hashutil(unittest.TestCase):
hashutil.bytehex_to_hash(
self.hex_checksums[algo].encode()))
+ @istest
+ def new_hash_unsupported_hashing_algorithm(self):
+ try:
+ hashutil._new_hash('blake2:10')
+ except ValueError as e:
+ self.assertEquals(str(e),
+ 'Unsupported hashing algorithm blake2:10')
+
+ @patch('swh.model.hashutil.sys')
+ @istest
+ def new_hash_unexpected_hashing_algo(self, mock_sys):
+ mock_sys.version_info = MagicMock(major=3, minor=6)
+
+ try:
+ hashutil._new_hash('blake3:256')
+ except ValueError as e:
+ self.assertEquals(str(e),
+ 'Unexpected hashing algorithm blake3:256, '
+ 'expected one of sha1, sha1_git, sha256')
+
+ @patch('swh.model.hashutil.sys')
+ @patch('swh.model.hashutil.hashlib')
+ @istest
+ def new_hash_blake2b(self, mock_hashlib, mock_sys):
+ mock_sys.version_info = MagicMock(major=3, minor=6)
+ mock_hashlib.blake2b.return_value = 'some-hashlib-object'
+
+ h = hashutil._new_hash('blake2b:256')
+
+ self.assertEquals(h, 'some-hashlib-object')
+ mock_hashlib.blake2b.assert_called_with(digest_size=256)
+
+ @patch('swh.model.hashutil.sys')
+ @patch('swh.model.hashutil.hashlib')
+ @istest
+ def new_hash_blake2s(self, mock_hashlib, mock_sys):
+ mock_sys.version_info = MagicMock(major=3, minor=6)
+ mock_hashlib.blake2s.return_value = 'some-hashlib-object'
+
+ h = hashutil._new_hash('blake2s:128')
+
+ self.assertEquals(h, 'some-hashlib-object')
+ mock_hashlib.blake2s.assert_called_with(digest_size=128)
+
class HashlibGit(unittest.TestCase):
--
GitLab