[qa] py2: Unfiddle strings into bytes explicitly in ZMQ RPC test

Extracted from bitcoin/bitcoin#7853
commit faa41ee204124da19dcf1e5b8a3aef1e216bf5e6

qa/rpc-tests/test_framework/util.py

@@ -1,6 +1,8 @@
 # Copyright (c) 2014 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+
 #
 # Helpful routines for regression testing
 #
@@ -9,6 +11,8 @@
 import os
 import sys
 
+from binascii import hexlify, unhexlify
+from base64 import b64encode
 from decimal import Decimal, ROUND_DOWN
 import json
 import random
@@ -32,6 +36,15 @@ def check_json_precision():
     if satoshis != 2000000000000003:
         raise RuntimeError("JSON encode/decode loses precision")
 
+def bytes_to_hex_str(byte_str):
+    return hexlify(byte_str).decode('ascii')
+
+def hex_str_to_bytes(hex_str):
+    return unhexlify(hex_str.encode('ascii'))
+
+def str_to_b64str(string):
+    return b64encode(string.encode('utf-8')).decode('ascii')
+
 def sync_blocks(rpc_connections, wait=1):
     """
     Wait until everybody has the same block count

qa/rpc-tests/zmq_test.py

@@ -28,8 +28,8 @@ class ZMQTest (BitcoinTestFramework):
     def setup_nodes(self):
         self.zmqContext = zmq.Context()
         self.zmqSubSocket = self.zmqContext.socket(zmq.SUB)
-        self.zmqSubSocket.setsockopt(zmq.SUBSCRIBE, "hashblock")
-        self.zmqSubSocket.setsockopt(zmq.SUBSCRIBE, "hashtx")
+        self.zmqSubSocket.setsockopt(zmq.SUBSCRIBE, b"hashblock")
+        self.zmqSubSocket.setsockopt(zmq.SUBSCRIBE, b"hashtx")
         self.zmqSubSocket.connect("tcp://127.0.0.1:%i" % self.port)
         return start_nodes(4, self.options.tmpdir, extra_args=[
             ['-zmqpubhashtx=tcp://127.0.0.1:'+str(self.port), '-zmqpubhashblock=tcp://127.0.0.1:'+str(self.port)],
@@ -46,13 +46,13 @@ class ZMQTest (BitcoinTestFramework):
 
         print "listen..."
         msg = self.zmqSubSocket.recv_multipart()
-        topic = str(msg[0])
+        topic = msg[0]
         body = msg[1]
 
         msg = self.zmqSubSocket.recv_multipart()
-        topic = str(msg[0])
+        topic = msg[0]
         body = msg[1]
-        blkhash = binascii.hexlify(body)
+        blkhash = bytes_to_hex_str(body)
 
         assert_equal(genhashes[0], blkhash) #blockhash from generate must be equal to the hash received over zmq
 
@@ -63,10 +63,10 @@ class ZMQTest (BitcoinTestFramework):
         zmqHashes = []
         for x in range(0,n*2):
             msg = self.zmqSubSocket.recv_multipart()
-            topic = str(msg[0])
+            topic = msg[0]
             body = msg[1]
-            if topic == "hashblock":
-                zmqHashes.append(binascii.hexlify(body))
+            if topic == b"hashblock":
+                zmqHashes.append(bytes_to_hex_str(body))
 
         for x in range(0,n):
             assert_equal(genhashes[x], zmqHashes[x]) #blockhash from generate must be equal to the hash received over zmq
@@ -77,11 +77,11 @@ class ZMQTest (BitcoinTestFramework):
 
         # now we should receive a zmq msg because the tx was broadcast
         msg = self.zmqSubSocket.recv_multipart()
-        topic = str(msg[0])
+        topic = msg[0]
         body = msg[1]
         hashZMQ = ""
-        if topic == "hashtx":
-            hashZMQ = binascii.hexlify(body)
+        if topic == b"hashtx":
+            hashZMQ = bytes_to_hex_str(body)
 
         assert_equal(hashRPC, hashZMQ) #blockhash from generate must be equal to the hash received over zmq