notify: add ability to notify using a remote action

Signed-off-by: Pieter Willekens <me@pataar.nl>

docs/configuration.md

@@ -1924,7 +1924,8 @@ events: *
 body: "Your printer status has changed to {event_name}"
 #   The body of the notification. This option accepts Jinja2 templates.
 #   You can use {event_name} to print the current event trigger name. And {event_args} for
-#   the arguments that came with it.
+#   the arguments that came with it. When using the notify functionality in a macro context, you can
+#   use {event_message} to print out your message.
 title:
 #   The optional title of the notification. Just as the body, this option accepts Jinja2 templates.
 attach:
@@ -1953,6 +1954,25 @@ url: tgram://{bottoken}/{ChatID}
 events: error
 body: {event_args[1].message}
 attach: http://192.168.1.100/webcam/?action=snapshot
+
+[notifier gcode_telegram]
+url: tgram://{bottoken}/{ChatID}
+events: gcode
+body: {event_message}
+attach: http://192.168.1.100/webcam/?action=snapshot
+```
+
+#### Notifying from Klipper
+It is possible to invoke your notifiers from the Klippy host, this can be done
+with a gcode_macro, such as:
+```ini
+# printer.cfg
+
+[gcode_macro NOTIFY_FILAMENT_CHANGE]
+gcode:
+  {action_call_remote_method("notify",
+                             name="telegram",
+                             message="Filament change needed!")}
 ```
 
 ### `[simplyprint]`

moonraker/components/notifier.py

@@ -35,6 +35,7 @@ class Notifier:
         prefix_sections = config.get_prefix_sections("notifier")
 
         self.register_events(config)
+        self.register_remote_actions()
 
         for section in prefix_sections:
             cfg = config[section]
@@ -53,6 +54,16 @@ class Notifier:
                 continue
             self.notifiers[notifier.get_name()] = notifier
 
+    def register_remote_actions(self):
+        self.server.register_remote_method("notify", self.notify_action)
+
+    async def notify_action(self, name: str, message: str = ""):
+        if name not in self.notifiers:
+            raise self.server.error(f"Notifier '{name}' not found", 404)
+        notifier = self.notifiers[name]
+
+        await notifier.notify("remote_action", [], message)
+
     def register_events(self, config: ConfigHelper):
 
         self.events["started"] = NotifierEvent(
@@ -145,10 +156,13 @@ class NotifierInstance:
 
         self.apprise.add(self.url)
 
-    async def notify(self, event_name: str, event_args: List) -> None:
+    async def notify(
+        self, event_name: str, event_args: List, message: str = ""
+    ) -> None:
         context = {
             "event_name": event_name,
-            "event_args": event_args
+            "event_args": event_args,
+            "event_message": message
         }
 
         rendered_title = (