Merge bitcoin#22490: test: Disable automatic connections per default in the functional tests

8ca51af test: Disable automatic connections by default (Martin Zumsande)

Pull request description:

  A node normally doesn't make automatic connections to peers in the functional tests because neither DNS seeds nor hardcoded peers are available on regtest. However, when random entries are inserted into addrman as part of a functional test (e.g. while testing addr relay), `ThreadOpenConnections` will periodically try to connect to them, resulting in log entries such as:
  `[opencon] [net.cpp:400] [ConnectNode] trying connection 18.166.1.1:8333 lastseen=0.0hrs`

  I don't think it's desirable that functional tests try to connect to random computers on the internet, aside from the possibility that at some point in time someone out there might actually answer in a way to ruin a test.

  This PR fixes this problem by disabling  `ThreadOpenConnections` by adding `-connect=0` to the default args, and adding exceptions only when needed for the test to pass.

ACKs for top commit:
  tryphe:
    Concept ACK, light code review ACK 8ca51af

Tree-SHA512: bcfb2de610e6c35a97a2bd7ad6267e968b1ac7529638d99276993cd5bc93ce9919d54e22d6dc84e1b02ecd626ab6554e201693552ea065c29794eece38c43f7d

Author: MarcoFalke

test/functional/feature_anchors.py

@@ -20,6 +20,7 @@
 class AnchorsTest(BitcoinTestFramework):
     def set_test_params(self):
         self.num_nodes = 1
+        self.disable_autoconnect = False
 
     def run_test(self):
         node_anchors_path = os.path.join(

test/functional/feature_config_args.py

@@ -17,6 +17,7 @@ def set_test_params(self):
         self.num_nodes = 1
         self.supports_cli = False
         self.wallet_names = []
+        self.disable_autoconnect = False
 
     def test_config_file_parser(self):
         self.log.info('Test config file parser')

test/functional/test_framework/test_framework.py

@@ -142,6 +142,9 @@ def __init__(self):
         # By default the wallet is not required. Set to true by skip_if_no_wallet().
         # When False, we ignore wallet_names regardless of what it is.
         self.requires_wallet = False
+        # Disable ThreadOpenConnections by default, so that adding entries to
+        # addrman will not result in automatic connections to them.
+        self.disable_autoconnect = True
         self.set_test_params()
         assert self.wallet_names is None or len(self.wallet_names) <= self.num_nodes
         if self.options.timeout_scale != 1:
@@ -455,7 +458,7 @@ def setup_network(self):
     def setup_nodes(self):
         """Override this method to customize test node setup"""
 
-        """If this method is updated - backport changes to  DashTestFramework.setup_nodes"""
+        """ NOTE! If this method is updated - backport changes to  DashTestFramework.setup_nodes"""
         self.add_nodes(self.num_nodes, self.extra_args)
         self.start_nodes()
         if self.requires_wallet:
@@ -947,7 +950,7 @@ def _initialize_chain(self):
         if not os.path.isdir(cache_node_dir):
             self.log.debug("Creating cache directory {}".format(cache_node_dir))
 
-            initialize_datadir(self.options.cachedir, CACHE_NODE_ID, self.chain)
+            initialize_datadir(self.options.cachedir, CACHE_NODE_ID, self.chain, self.disable_autoconnect)
             self.nodes.append(
                 TestNode(
                     CACHE_NODE_ID,
@@ -1012,15 +1015,15 @@ def cache_path(*paths):
             self.log.debug("Copy cache directory {} to node {}".format(cache_node_dir, i))
             to_dir = get_datadir_path(self.options.tmpdir, i)
             shutil.copytree(cache_node_dir, to_dir)
-            initialize_datadir(self.options.tmpdir, i, self.chain)  # Overwrite port/rpcport in dash.conf
+            initialize_datadir(self.options.tmpdir, i, self.chain, self.disable_autoconnect)  # Overwrite port/rpcport in dash.conf
 
     def _initialize_chain_clean(self):
         """Initialize empty blockchain for use by the test.
 
         Create an empty blockchain and num_nodes wallets.
         Useful if a test case wants complete control over initialization."""
         for i in range(self.num_nodes):
-            initialize_datadir(self.options.tmpdir, i, self.chain)
+            initialize_datadir(self.options.tmpdir, i, self.chain, self.disable_autoconnect)
 
     def skip_if_no_py3_zmq(self):
         """Attempt to import the zmq package and skip the test if the import fails."""
@@ -1518,6 +1521,9 @@ def set_dash_test_params(self, num_nodes, masterodes_count, extra_args=None, evo
             extra_args = [[]] * num_nodes
         assert_equal(len(extra_args), num_nodes)
         self.extra_args = [copy.deepcopy(a) for a in extra_args]
+        # masternodes creates connections for quorums by ThreadOpenConnections too
+        # it can't be disabled for DashTestFramework same as BitcoinTestFramework
+        self.disable_autoconnect = False
 
         # LLMQ default test params (no need to pass -llmqtestparams)
         self.llmq_size = 3

test/functional/test_framework/util.py

@@ -371,17 +371,17 @@ def rpc_url(datadir, i, chain, rpchost=None):
 ################
 
 
-def initialize_datadir(dirname, n, chain):
+def initialize_datadir(dirname, n, chain, disable_autoconnect=True):
     datadir = get_datadir_path(dirname, n)
     if not os.path.isdir(datadir):
         os.makedirs(datadir)
-    write_config(os.path.join(datadir, "dash.conf"), n=n, chain=chain)
+    write_config(os.path.join(datadir, "dash.conf"), n=n, chain=chain, disable_autoconnect=disable_autoconnect)
     os.makedirs(os.path.join(datadir, 'stderr'), exist_ok=True)
     os.makedirs(os.path.join(datadir, 'stdout'), exist_ok=True)
     return datadir
 
 
-def write_config(config_path, *, n, chain, extra_config=""):
+def write_config(config_path, *, n, chain, extra_config="", disable_autoconnect=True):
     (chain_name_conf_arg, chain_name_conf_arg_value, chain_name_conf_section) = get_chain_conf_names(chain)
     with open(config_path, 'w', encoding='utf8') as f:
         if chain_name_conf_arg:
@@ -408,6 +408,8 @@ def write_config(config_path, *, n, chain, extra_config=""):
         f.write("shrinkdebugfile=0\n")
         # To improve SQLite wallet performance so that the tests don't timeout, use -unsafesqlitesync
         f.write("unsafesqlitesync=1\n")
+        if disable_autoconnect:
+            f.write("connect=0\n")
         f.write(extra_config)