Add CRC Pubkey

duniterpy/documents/crc_pubkey.py

+import base58
+import re
+import hashlib
+from .constants import pubkey_regex
+
+
+class CRCPubkey:
+    """
+    Class to implement a crc on a pubkey
+    """
+    re_crc_pubkey = re.compile("({pubkey_regex}):([A-Za-z0-9]{{3}})".format(pubkey_regex=pubkey_regex))
+
+    def __init__(self, pubkey, crc):
+        """
+        Creates a pubkey with a crc
+        :param pubkey:
+        """
+        self.pubkey = pubkey
+        self.crc = crc
+
+    @classmethod
+    def from_str(cls, str):
+        data = CRCPubkey.re_crc_pubkey.match(str)
+        pubkey = data.group(1)
+        crc = data.group(2)
+        return cls(pubkey, crc)
+
+    @classmethod
+    def from_pubkey(cls, pubkey):
+        hash_root = hashlib.sha256()
+        hash_root.update(base58.b58decode(pubkey))
+        hash_squared = hashlib.sha256()
+        hash_squared.update(hash_root.digest())
+        b58_checksum = base58.b58encode(hash_squared.digest())
+
+        crc = b58_checksum[:3]
+        return cls(pubkey, crc)
+
+    def is_valid(self):
+        return CRCPubkey.from_pubkey(self.pubkey).crc == self.crc

tests/documents/test_crc_pubkey.py

+import unittest
+from duniterpy.documents.crc_pubkey import CRCPubkey
+
+
+class Test_CRCPubkey(unittest.TestCase):
+    def test_from_pubkey(self):
+        crc_pubkey = CRCPubkey.from_pubkey("J4c8CARmP9vAFNGtHRuzx14zvxojyRWHW2darguVqjtX")
+        self.assertEquals(crc_pubkey.crc, "KAv")

tests/documents/test_peer.py

@@ -19,6 +19,7 @@ OTHER_PROTOCOL 88.77.66.55 9001
 dkaXIiCYUJtCg8Feh/BKvPYf4uFH9CJ/zY6J4MlA9BsjmcMe4YAblvNt/gJy31b1aGq3ue3h14mLMCu84rraDg==
 """
 
+
 test_weird_ipv6_peer = """Version: 10
 Type: Peer
 Currency: g1
@@ -30,6 +31,7 @@ BMAS duniter.aquilenet.fr 443
 dkaXIiCYUJtCg8Feh/BKvPYf4uFH9CJ/zY6J4MlA9BsjmcMe4YAblvNt/gJy31b1aGq3ue3h14mLMCu84rraDg==
 """
 
+
 class TestPeer(unittest.TestCase):
     def test_fromraw(self):
         peer = Peer.from_signed_raw(rawpeer)