[tests] Remove rpc_zmq.py

rpc_zmq.py is racy and fails intermittently. Remove that test file and
move the getzmqnotifications RPC test into interface_zmq.py

test/functional/interface_zmq.py

@@ -14,6 +14,7 @@ from test_framework.util import (
 )
 from io import BytesIO
 
+ADDRESS = "tcp://127.0.0.1:28332"
 
 class ZMQSubscriber:
     def __init__(self, socket, topic):
@@ -51,11 +52,10 @@ class ZMQTest (BitcoinTestFramework):
         # that this test fails if the publishing order changes.
         # Note that the publishing order is not defined in the documentation and
         # is subject to change.
-        address = "tcp://127.0.0.1:28332"
         self.zmq_context = zmq.Context()
         socket = self.zmq_context.socket(zmq.SUB)
         socket.set(zmq.RCVTIMEO, 60000)
-        socket.connect(address)
+        socket.connect(ADDRESS)
 
         # Subscribe to all available topics.
         self.hashblock = ZMQSubscriber(socket, b"hashblock")
@@ -64,7 +64,7 @@ class ZMQTest (BitcoinTestFramework):
         self.rawtx = ZMQSubscriber(socket, b"rawtx")
 
         self.extra_args = [
-            ["-zmqpub%s=%s" % (sub.topic.decode(), address) for sub in [self.hashblock, self.hashtx, self.rawblock, self.rawtx]],
+            ["-zmqpub%s=%s" % (sub.topic.decode(), ADDRESS) for sub in [self.hashblock, self.hashtx, self.rawblock, self.rawtx]],
             [],
         ]
         self.add_nodes(self.num_nodes, self.extra_args)
@@ -117,5 +117,15 @@ class ZMQTest (BitcoinTestFramework):
         hex = self.rawtx.receive()
         assert_equal(payment_txid, bytes_to_hex_str(hash256(hex)))
 
+        self.log.info("Test the getzmqnotifications RPC")
+        assert_equal(self.nodes[0].getzmqnotifications(), [
+            {"type": "pubhashblock", "address": ADDRESS},
+            {"type": "pubhashtx", "address": ADDRESS},
+            {"type": "pubrawblock", "address": ADDRESS},
+            {"type": "pubrawtx", "address": ADDRESS},
+        ])
+
+        assert_equal(self.nodes[1].getzmqnotifications(), [])
+
 if __name__ == '__main__':
     ZMQTest().main()

test/functional/rpc_zmq.py

@@ -1,37 +0,0 @@
-#!/usr/bin/env python3
-# Copyright (c) 2018 The Bitcoin Core developers
-# Distributed under the MIT software license, see the accompanying
-# file COPYING or http://www.opensource.org/licenses/mit-license.php.
-"""Test for the ZMQ RPC methods."""
-
-from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal
-
-
-class RPCZMQTest(BitcoinTestFramework):
-
-    address = "tcp://127.0.0.1:28332"
-
-    def set_test_params(self):
-        self.num_nodes = 1
-        self.setup_clean_chain = True
-
-    def skip_test_if_missing_module(self):
-        self.skip_if_no_py3_zmq()
-        self.skip_if_no_bitcoind_zmq()
-
-    def run_test(self):
-        self._test_getzmqnotifications()
-
-    def _test_getzmqnotifications(self):
-        self.restart_node(0, extra_args=[])
-        assert_equal(self.nodes[0].getzmqnotifications(), [])
-
-        self.restart_node(0, extra_args=["-zmqpubhashtx=%s" % self.address])
-        assert_equal(self.nodes[0].getzmqnotifications(), [
-            {"type": "pubhashtx", "address": self.address},
-        ])
-
-
-if __name__ == '__main__':
-    RPCZMQTest().main()

test/functional/test_runner.py

@@ -152,7 +152,6 @@ BASE_SCRIPTS = [
     'feature_versionbits_warning.py',
     'rpc_preciousblock.py',
     'wallet_importprunedfunds.py',
-    'rpc_zmq.py',
     'rpc_signmessage.py',
     'feature_nulldummy.py',
     'mempool_accept.py',