Added hash method in transaction

Author: Oleksandr Anyshchenko

.gitignore

@@ -3,4 +3,7 @@ __pycache__
 .pytest_cache
 Pipfile.lock
 /*bin
-*log
+*log
+*.pyc
+.vscode
+.idea/

exonum/transactions.py

@@ -5,7 +5,7 @@
 from itertools import chain
 
 from pysodium import crypto_sign_BYTES as SIGNATURE_SZ
-from pysodium import crypto_sign_detached
+from pysodium import crypto_sign_detached, crypto_hash_sha256
 
 from .datatypes import EncodingStruct, ExonumBase, TxHeader
 from .error import IllegalServiceId, NotEncodingStruct
@@ -100,7 +100,13 @@ def tx(self, secret_key, hex=False):
                                    in plain.items()
                                    if k not in meta_fields}
                 del message["payload_sz"]
+                del message['network_id']  # Redundant field in JSON
                 return message
 
+            def hash(self, secret_key):
+                tx_bytes = self.tx(secret_key, hex=True)
+                tx_hash = crypto_hash_sha256(tx_bytes)
+                return codecs.encode(tx_hash, "hex").decode("utf-8")
+
         self.tx.append(cls.__name__)
         return Tx

tests/test_serde.py

@@ -1,8 +1,6 @@
 # coding: utf-8
 from uuid import uuid4
-
 from six import with_metaclass
-
 from exonum.datatypes import (Decimal, EncodingStruct, SocketAddr, Str, Uuid,
                               Vec, i64, u8, u16)
 
@@ -71,14 +69,15 @@ class X(with_metaclass(EncodingStruct)):
     assert raw == z
 
 
-# def test_segment_vector():
-#     class X(with_metaclass(EncodingStruct)):
-#         f = Vec(Str)
+def test_segment_vector():
+    class X(with_metaclass(EncodingStruct)):
+        f = Vec(Str)
+
+    x = X(f=[u"am", u"i", u"working", u"or", u"what?"])
+    raw = x.to_bytes()
+    xx = X.read_buffer(raw)
+    assert xx.f.val == x.f.val
 
-#     x = X(f=[u"am", u"i", u"working", u"or", u"what?"])
-#     raw = x.to_bytes()
-#     xx = X.read_buffer(raw)
-#     assert xx.f.val == x.f.val
 
 def test_inner():
     class X(with_metaclass(EncodingStruct)):

tests/test_tx.py

@@ -11,6 +11,7 @@
 
 transactions = tx.transactions(service_id=250)
 
+
 # py3
 # class Policy(metaclass=exonum.EncodingStruct):
 #    ...