pyln: add ability to subscribe to all notifications.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

contrib/pyln-client/pyln/client/plugin.py

@@ -659,10 +659,13 @@ class Plugin(object):
             self.log(traceback.format_exc())
 
     def _dispatch_notification(self, request: Request) -> None:
-        if request.method not in self.subscriptions:
-            raise ValueError("No subscription for {name} found.".format(
-                name=request.method))
-        func = self.subscriptions[request.method]
+        if request.method in self.subscriptions:
+            func = self.subscriptions[request.method]
+        # Wildcard 'all' subscriptions using asterisk
+        elif '*' in self.subscriptions:
+            func = self.subscriptions['*']
+        else:
+            raise ValueError(f"No subscription for {request.method} found.")
 
         try:
             self._exec_func(func, request)

tests/plugins/all_notifications.py

@@ -0,0 +1,17 @@
+#!/usr/bin/env python3
+from pyln.client import Plugin
+import sys
+
+
+plugin = Plugin()
+
+
+@plugin.subscribe("*")
+def on_any_notification(request, **kwargs):
+    plugin.log("notification {}: {}".format(request.method, kwargs))
+    if request.method == 'shutdown':
+        # A plugin which subscribes to shutdown is expected to exit itself.
+        sys.exit(0)
+
+
+plugin.run()

tests/test_plugin.py

@@ -4248,3 +4248,20 @@ def test_plugin_persist_option(node_factory):
     assert c['value_str'] == "Static option"
     assert c['plugin'] == plugin_path
     assert l1.rpc.call("hello") == "Static option world"
+
+
+def test_all_subscription(node_factory, directory):
+    """Ensure that registering for all notifications works."""
+    plugin = os.path.join(os.getcwd(), 'tests/plugins/all_notifications.py')
+    
+    l1, l2 = node_factory.line_graph(2, opts={"plugin": plugin})
+
+    l1.stop()
+
+    # There will be a lot of these!
+    for notstr in ("block_added: {'block_added': {'hash': ",
+                   "balance_snapshot: {'balance_snapshot': {'node_id': ",
+                   "connect: {'connect': {'id': ",
+                   "channel_state_changed: {'channel_state_changed': {'peer_id': ",
+                   "shutdown: {}"):
+        assert l1.daemon.is_in_log(f".*plugin-all_notifications.py: notification {notstr}.*")