Merge pull request #85 from alecalve/bech32

Add support for bech32 addresses

Author: alecalve

blockchain_parser/address.py

@@ -10,32 +10,39 @@
 # in the LICENSE file.
 
 from bitcoin import base58
+from bitcoin.bech32 import CBech32Data
 from .utils import btc_ripemd160, double_sha256
 
 
 class Address(object):
     """Represents a bitcoin address"""
 
-    def __init__(self, hash, public_key, address, type):
+    def __init__(self, hash, public_key, address, type, segwit_version):
         self._hash = hash
         self.public_key = public_key
         self._address = address
         self.type = type
+        self._segwit_version = segwit_version
 
     def __repr__(self):
         return "Address(addr=%s)" % self.address
 
     @classmethod
     def from_public_key(cls, public_key):
         """Constructs an Address object from a public key"""
-        return cls(None, public_key, None, "normal")
+        return cls(None, public_key, None, "normal", None)
 
     @classmethod
     def from_ripemd160(cls, hash, type="normal"):
         """Constructs an Address object from a RIPEMD-160 hash, it may be a
         normal address or a P2SH address, the latter is indicated by setting
         type to 'p2sh'"""
-        return cls(hash, None, None, type)
+        return cls(hash, None, None, type, None)
+
+    @classmethod
+    def from_bech32(cls, hash, segwit_version):
+        """Constructs an Address object from a bech32 hash."""
+        return cls(hash, None, None, "bech32", segwit_version)
 
     @property
     def hash(self):
@@ -47,12 +54,18 @@ def hash(self):
 
     @property
     def address(self):
-        """Returns the base58 encoded representation of this address"""
+        """Returns the encoded representation of this address.
+        If SegWit, it's encoded using bech32, otherwise using base58
+        """
         if self._address is None:
-            version = b'\x00' if self.type == "normal" else b'\x05'
-            checksum = double_sha256(version + self.hash)
+            if self.type != "bech32":
+                version = b'\x00' if self.type == "normal" else b'\x05'
+                checksum = double_sha256(version + self.hash)
 
-            self._address = base58.encode(version + self.hash + checksum[:4])
+                self._address = base58.encode(version + self.hash + checksum[:4])
+            else:
+                bech_encoded = CBech32Data.from_bytes(self._segwit_version, self._hash)
+                self._address = str(bech_encoded)
         return self._address
 
     def is_p2sh(self):

blockchain_parser/output.py

@@ -71,6 +71,12 @@ def addresses(self):
                 n = self.script.operations[-2]
                 for operation in self.script.operations[1:1+n]:
                     self._addresses.append(Address.from_public_key(operation))
+            elif self.type == "p2wpkh":
+                address = Address.from_bech32(self.script.operations[1], 0)
+                self._addresses.append(address)
+            elif self.type == "p2wsh":
+                address = Address.from_bech32(self.script.operations[1], 0)
+                self._addresses.append(address)
 
         return self._addresses
 
@@ -92,6 +98,12 @@ def is_multisig(self):
     def is_unknown(self):
         return self.script.is_unknown()
 
+    def is_p2wpkh(self):
+        return self.script.is_p2wpkh()
+
+    def is_p2wsh(self):
+        return self.script.is_p2wsh()
+
     @property
     def type(self):
         """Returns the output's script type as a string"""
@@ -114,4 +126,10 @@ def type(self):
         if self.is_return():
             return "OP_RETURN"
 
+        if self.is_p2wpkh():
+            return "p2wpkh"
+
+        if self.is_p2wsh():
+            return "p2wsh"
+
         return "unknown"

blockchain_parser/script.py

@@ -98,6 +98,12 @@ def is_return(self):
     def is_p2sh(self):
         return self.script.is_p2sh()
 
+    def is_p2wsh(self):
+        return self.script.is_witness_v0_scripthash()
+
+    def is_p2wpkh(self):
+        return self.script.is_witness_v0_keyhash()
+
     def is_pubkey(self):
         return len(self.operations) == 2 \
             and self.operations[-1] == OP_CHECKSIG \

blockchain_parser/tests/bech32_p2wpkh.txt

@@ -0,0 +1 @@
+020000000001016dee1ae581bf13134aa6aea8051b974c064bc2227094dc971561aac44a02ec500000000000ffffffff023cad17000000000017a914682ca28dc5e71f0139ad95a71c639c9e61c9c82e8773a33a0400000000160014a89e7f54db49b31364169f3e8982fcb5d3275e8b024830450221009424d2dcee3e8a00261cd3df8c7a103b14a8f0853075118329a21856f9cef36802207b9a2d51347bd2f73359375260e29fb67c67fa87825a625362a16b4a3c38f2350121030731907d43214f178bd4c9e279ac22043858001e220a935fff94f5fd3e8606a300000000

blockchain_parser/tests/bech32_p2wsh.txt

@@ -0,0 +1 @@
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

blockchain_parser/tests/test_transaction.py

@@ -51,6 +51,24 @@ def test_bip69(self):
         tx = Transaction(data)
         self.assertTrue(tx.uses_bip69())
 
+    def test_bech32_p2wpkh(self):
+        example_tx = "bech32_p2wpkh.txt"
+        with open(os.path.join(dir_path, example_tx)) as f:
+            data = a2b_hex(f.read().strip())
+
+        tx = Transaction(data)
+        self.assertEqual(["3BBqfnaPbgi5KWECWdFpvryUfw7QatWy37"], [a.address for a in tx.outputs[0].addresses])
+        self.assertEqual(["bc1q4z0874xmfxe3xeqknulgnqhukhfjwh5tvjrr2x"], [a.address for a in tx.outputs[1].addresses])
+
+    def test_bech32_p2wsh(self):
+        example_tx = "bech32_p2wsh.txt"
+        with open(os.path.join(dir_path, example_tx)) as f:
+            data = a2b_hex(f.read().strip())
+
+        tx = Transaction(data)
+        self.assertEqual(["3GMKKFPNUg13VktgihUD8QfXVQRBdoDNDf"], [a.address for a in tx.outputs[0].addresses])
+        self.assertEqual(["bc1qday7wsftyv4r6qkpn8907s8fy3kexkny0xwrd8d4wlk06zffzyuqpp629n"], [a.address for a in tx.outputs[1].addresses])
+
     def test_segwit(self):
         example_tx = "segwit.txt"
         with open(os.path.join(dir_path, example_tx)) as f:

requirements.txt

@@ -1,3 +1,3 @@
-python-bitcoinlib==0.5.0
-plyvel==1.0.4
-coverage==4.0.2
+python-bitcoinlib==0.11.0
+plyvel==1.2.0
+coverage==4.0.2

setup.py

@@ -19,7 +19,7 @@
         'Topic :: Software Development :: Libraries',
     ],
     install_requires=[
-        'python-bitcoinlib==0.5.0',
-        'plyvel==1.0.4'
+        'python-bitcoinlib==0.11.0',
+        'plyvel==1.2.0'
     ]
 )