Move hash_data to the crypto module

bigchaindb/core.py

@@ -331,7 +331,7 @@ class Bigchain(object):
 
         # Calculate the hash of the new block
         block_data = util.serialize(block)
-        block_hash = util.hash_data(block_data)
+        block_hash = crypto.hash_data(block_data)
         block_signature = crypto.PrivateKey(self.me_private).sign(block_data)
 
         block = {
@@ -357,7 +357,7 @@ class Bigchain(object):
         """
 
         # 1. Check if current hash is correct
-        calculated_hash = util.hash_data(util.serialize(block['block']))
+        calculated_hash = crypto.hash_data(util.serialize(block['block']))
         if calculated_hash != block['id']:
             raise exceptions.InvalidHash()
 

bigchaindb/crypto.py

@@ -2,6 +2,8 @@
 
 import binascii
 import base58
+
+import sha3
 import bitcoin
 
 from cryptography.hazmat.backends import default_backend
@@ -144,3 +146,10 @@ def generate_key_pair():
 
     return (private_value_base58, public_value_compressed_base58)
 
+
+def hash_data(data):
+    """Hash the provided data using SHA3-256"""
+
+    return sha3.sha3_256(data.encode()).hexdigest()
+
+

bigchaindb/util.py

@@ -1,4 +1,3 @@
-import sha3
 
 import json
 import time
@@ -7,7 +6,7 @@ from datetime import datetime
 
 import bigchaindb
 from bigchaindb import exceptions
-from bigchaindb.crypto import PrivateKey, PublicKey
+from bigchaindb.crypto import PrivateKey, PublicKey, hash_data
 
 
 class ProcessGroup(object):
@@ -158,10 +157,6 @@ def create_and_sign_tx(private_key, current_owner, new_owner, tx_input, operatio
     return sign_tx(tx, private_key)
 
 
-def hash_data(data):
-    return sha3.sha3_256(data.encode()).hexdigest()
-
-
 def check_hash_and_signature(transaction):
     # Check hash of the transaction
     calculated_hash = hash_data(serialize(transaction['transaction']))

tests/db/test_bigchain_api.py

@@ -8,8 +8,7 @@ import rethinkdb as r
 import bigchaindb
 from bigchaindb import util
 from bigchaindb import exceptions
-from bigchaindb.crypto import PrivateKey, PublicKey, generate_key_pair
-from bigchaindb.util import hash_data
+from bigchaindb.crypto import PrivateKey, PublicKey, generate_key_pair, hash_data
 from bigchaindb.voter import Voter
 from bigchaindb.block import Block