manifest: Support mapping Manifest hash names to hashlib

2 files changed, 36 insertions, 0 deletions

diff --git a/gemato/manifest.py b/gemato/manifest.py
index d094c87..065b852 100644
--- a/gemato/manifest.py
+++ b/gemato/manifest.py
@@ -369,3 +369,26 @@ class ManifestFile(object):
                 mdir = os.path.dirname(e.path)
                 if path.startswith(mdir + '/'):
                     yield e
+
+
+MANIFEST_HASH_MAPPING = {
+    'MD5': 'md5',
+    'SHA1': 'sha1',
+    'SHA256': 'sha256',
+    'SHA512': 'sha512',
+    'RMD160': 'ripemd160',
+    'WHIRLPOOL': 'whirlpool',
+    'BLAKE2B': 'blake2b',
+    'BLAKE2S': 'blake2s',
+    'SHA3_256': 'sha3_256',
+    'SHA3_512': 'sha3_512',
+}
+
+
+def manifest_hashes_to_hashlib(hashes):
+    """
+    Return the hashlib hash names corresponding to the Manifest names
+    in @hashes. Returns an iterable.
+    """
+    for h in hashes:
+        yield MANIFEST_HASH_MAPPING[h]
diff --git a/tests/test_manifest.py b/tests/test_manifest.py
index feb4060..8729eb9 100644
--- a/tests/test_manifest.py
+++ b/tests/test_manifest.py
@@ -341,3 +341,16 @@ class ManifestEntryTest(unittest.TestCase):
                 gemato.manifest.ManifestEntryAUX.from_list, ('AUX',))
         self.assertRaises(gemato.manifest.ManifestSyntaxError,
                 gemato.manifest.ManifestEntryAUX.from_list, ('AUX', 'foo'))
+
+
+class ManifestUtilityTest(unittest.TestCase):
+    def test_manifest_hashes_to_hashlib(self):
+        self.assertListEqual(list(
+                gemato.manifest.manifest_hashes_to_hashlib(['MD5', 'SHA1'])),
+            ['md5', 'sha1'])
+        self.assertListEqual(list(
+                gemato.manifest.manifest_hashes_to_hashlib(['RMD160'])),
+            ['ripemd160'])
+        self.assertListEqual(list(
+                gemato.manifest.manifest_hashes_to_hashlib(['SHA3_256', 'SHA256'])),
+            ['sha3_256', 'sha256'])