[test] Add test framework support to create outbound connections.

In the interest of increasing our P2P test coverage, add support to create
full-relay or block-relay-only connections. To support this, a P2P connection
spins up a listening thread & uses a callback to trigger the node initiating
the connection.

Co-authored-by: Anthony Towns <aj@erisian.com.au>

1 files changed, 26 insertions, 1 deletions

diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py
index e10ec1328b..b61d433652 100755
--- a/test/functional/test_framework/test_node.py
+++ b/test/functional/test_framework/test_node.py
@@ -71,6 +71,7 @@ class TestNode():
         """
 
         self.index = i
+        self.p2p_conn_index = 1
         self.datadir = datadir
         self.bitcoinconf = os.path.join(self.datadir, "bitcoin.conf")
         self.stdout_dir = os.path.join(self.datadir, "stdout")
@@ -517,7 +518,7 @@ class TestNode():
                 self._raise_assertion_error(assert_msg)
 
     def add_p2p_connection(self, p2p_conn, *, wait_for_verack=True, **kwargs):
-        """Add a p2p connection to the node.
+        """Add an inbound p2p connection to the node.
 
         This method adds the p2p connection to the self.p2ps list and also
         returns the connection to the caller."""
@@ -546,6 +547,29 @@ class TestNode():
 
         return p2p_conn
 
+    def add_outbound_p2p_connection(self, p2p_conn, *, p2p_idx, connection_type="outbound-full-relay", **kwargs):
+        """Add an outbound p2p connection from node. Either
+        full-relay("outbound-full-relay") or
+        block-relay-only("block-relay-only") connection.
+
+        This method adds the p2p connection to the self.p2ps list and returns
+        the connection to the caller.
+        """
+
+        def addconnection_callback(address, port):
+            self.log.debug("Connecting to %s:%d %s" % (address, port, connection_type))
+            self.addconnection('%s:%d' % (address, port), connection_type)
+
+        p2p_conn.peer_accept_connection(connect_cb=addconnection_callback, connect_id=p2p_idx + 1, net=self.chain, timeout_factor=self.timeout_factor, **kwargs)()
+
+        p2p_conn.wait_for_connect()
+        self.p2ps.append(p2p_conn)
+
+        p2p_conn.wait_for_verack()
+        p2p_conn.sync_with_ping()
+
+        return p2p_conn
+
     def num_test_p2p_connections(self):
         """Return number of test framework p2p connections to the node."""
         return len([peer for peer in self.getpeerinfo() if peer['subver'] == MY_SUBVERSION.decode("utf-8")])
@@ -555,6 +579,7 @@ class TestNode():
         for p in self.p2ps:
             p.peer_disconnect()
         del self.p2ps[:]
+
         wait_until_helper(lambda: self.num_test_p2p_connections() == 0, timeout_factor=self.timeout_factor)