basic invoice listeners.

lnbits/core/tasks.py

@@ -1,9 +1,13 @@
 import asyncio
-from typing import Optional, Awaitable
+from typing import Optional, List, Awaitable, Tuple, Callable
 from quart import Quart, Request, g
 from werkzeug.datastructures import Headers
 
-from lnbits.db import open_db
+from lnbits.db import open_db, open_ext_db
+from lnbits.settings import WALLET
+
+from .models import Payment
+from .crud import get_standalone_payment
 
 main_app: Optional[Quart] = None
 
@@ -31,3 +35,37 @@ def run_on_pseudo_request(awaitable: Awaitable):
 
     loop = asyncio.get_event_loop()
     loop.create_task(run(awaitable))
+
+
+invoice_listeners: List[Tuple[str, Callable[[Payment], Awaitable[None]]]] = []
+
+
+def register_invoice_listener(ext_name: str, callback: Callable[[Payment], Awaitable[None]]):
+    """
+    A method intended for extensions to call when they want to be notified about
+    new invoice payments incoming.
+    """
+    print("registering callback", callback)
+    invoice_listeners.append((ext_name, callback))
+
+
+async def webhook_handler():
+    handler = getattr(WALLET, "webhook_listener", None)
+    if handler:
+        await handler()
+
+
+async def invoice_listener(app):
+    run_on_pseudo_request(_invoice_listener())
+
+
+async def _invoice_listener():
+    async for checking_id in WALLET.paid_invoices_stream():
+        # do this just so the g object is available
+        g.db = await open_db()
+        payment = await get_standalone_payment(checking_id)
+        if payment.is_in:
+            await payment.set_pending(False)
+            for ext_name, cb in invoice_listeners:
+                g.ext_db = await open_ext_db(ext_name)
+                cb(payment)