register channel listeners instead of callbacks.

makes for a little less black magic and more reasonable use of nurseries
and less unnecessary pseudo-requests.

lnbits/app.py

@@ -12,7 +12,7 @@ from .core import core_app
 from .db import open_db, open_ext_db
 from .helpers import get_valid_extensions, get_js_vendored, get_css_vendored, url_for_vendored
 from .proxy_fix import ASGIProxyFix
-from .tasks import invoice_listener, webhook_handler, grab_app_for_later
+from .tasks import run_deferred_async, invoice_listener, webhook_handler, grab_app_for_later
 
 secure_headers = SecureHeaders(hsts=False)
 
@@ -111,6 +111,8 @@ def register_async_tasks(app):
 
     @app.before_serving
     async def listeners():
+        run_deferred_async(app.nursery)
+
         app.nursery.start_soon(invoice_listener)
         print("started global invoice_listener.")
 

lnbits/core/__init__.py

@@ -8,8 +8,8 @@ core_app: Blueprint = Blueprint(
 
 from .views.api import *  # noqa
 from .views.generic import *  # noqa
-from .tasks import on_invoice_paid
+from .tasks import register_listeners
 
-from lnbits.tasks import register_invoice_listener
+from lnbits.tasks import record_async
 
-register_invoice_listener("core", on_invoice_paid)
+core_app.record(record_async(register_listeners))

lnbits/core/models.py

@@ -70,6 +70,7 @@ class Payment(NamedTuple):
     preimage: str
     payment_hash: str
     extra: Dict
+    wallet_id: str
 
     @classmethod
     def from_row(cls, row: Row):
@@ -84,6 +85,7 @@ class Payment(NamedTuple):
             fee=row["fee"],
             memo=row["memo"],
             time=row["time"],
+            wallet_id=row["wallet"],
         )
 
     @property

lnbits/core/tasks.py

@@ -1,15 +1,22 @@
 import trio  # type: ignore
 from typing import List
 
-from .models import Payment
+from lnbits.tasks import register_invoice_listener
 
 sse_listeners: List[trio.MemorySendChannel] = []
 
 
-async def on_invoice_paid(payment: Payment):
-    for send_channel in sse_listeners:
-        try:
-            send_channel.send_nowait(payment)
-        except trio.WouldBlock:
-            print("removing sse listener", send_channel)
-            sse_listeners.remove(send_channel)
+async def register_listeners():
+    invoice_paid_chan_send, invoice_paid_chan_recv = trio.open_memory_channel(5)
+    register_invoice_listener(invoice_paid_chan_send)
+    await wait_for_paid_invoices(invoice_paid_chan_recv)
+
+
+async def wait_for_paid_invoices(invoice_paid_chan: trio.MemoryReceiveChannel):
+    async for payment in invoice_paid_chan:
+        for send_channel in sse_listeners:
+            try:
+                send_channel.send_nowait(payment)
+            except trio.WouldBlock:
+                print("removing sse listener", send_channel)
+                sse_listeners.remove(send_channel)

lnbits/core/views/api.py

@@ -128,6 +128,7 @@ async def api_payment(payment_hash):
 @api_check_wallet_key("invoice")
 async def api_payments_sse():
     g.db.close()
+    this_wallet_id = g.wallet.id
 
     send_payment, receive_payment = trio.open_memory_channel(0)
 
@@ -138,7 +139,8 @@ async def api_payments_sse():
 
     async def payment_received() -> None:
         async for payment in receive_payment:
-            await send_event.send(("payment", payment))
+            if payment.wallet_id == this_wallet_id:
+                await send_event.send(("payment", payment))
 
     async def repeat_keepalive():
         await trio.sleep(1)
@@ -160,7 +162,6 @@ async def api_payments_sse():
 
                 yield b"\n".join(message) + b"\r\n\r\n"
         except trio.Cancelled:
-            print("canceled!")
             return
 
     response = await make_response(

lnbits/extensions/lnurlp/__init__.py

@@ -7,8 +7,8 @@ lnurlp_ext: Blueprint = Blueprint("lnurlp", __name__, static_folder="static", te
 from .views_api import *  # noqa
 from .views import *  # noqa
 from .lnurl import *  # noqa
-from .tasks import on_invoice_paid
+from .tasks import register_listeners
 
-from lnbits.tasks import register_invoice_listener
+from lnbits.tasks import record_async
 
-register_invoice_listener("lnurlp", on_invoice_paid)
+lnurlp_ext.record(record_async(register_listeners))

lnbits/extensions/lnurlp/tasks.py

@@ -1,10 +1,23 @@
+import trio  # type: ignore
 import httpx
 
 from lnbits.core.models import Payment
+from lnbits.tasks import run_on_pseudo_request, register_invoice_listener
 
 from .crud import get_pay_link_by_invoice, mark_webhook_sent
 
 
+async def register_listeners():
+    invoice_paid_chan_send, invoice_paid_chan_recv = trio.open_memory_channel(2)
+    register_invoice_listener(invoice_paid_chan_send)
+    await wait_for_paid_invoices(invoice_paid_chan_recv)
+
+
+async def wait_for_paid_invoices(invoice_paid_chan: trio.MemoryReceiveChannel):
+    async for payment in invoice_paid_chan:
+        await run_on_pseudo_request(on_invoice_paid, payment)
+
+
 async def on_invoice_paid(payment: Payment) -> None:
     islnurlp = "lnurlp" == payment.extra.get("tag")
     if islnurlp:

lnbits/tasks.py

@@ -1,14 +1,13 @@
 import trio  # type: ignore
 from http import HTTPStatus
-from typing import Optional, Tuple, List, Callable, Awaitable
+from typing import Optional, List, Callable
 from quart import Request, g
 from quart_trio import QuartTrio
 from werkzeug.datastructures import Headers
 
-from lnbits.db import open_db, open_ext_db
+from lnbits.db import open_db
 from lnbits.settings import WALLET
 
-from lnbits.core.models import Payment
 from lnbits.core.crud import get_standalone_payment
 
 main_app: Optional[QuartTrio] = None
@@ -19,6 +18,21 @@ def grab_app_for_later(app: QuartTrio):
     main_app = app
 
 
+deferred_async: List[Callable] = []
+
+
+def record_async(func: Callable) -> Callable:
+    def recorder(state):
+        deferred_async.append(func)
+
+    return recorder
+
+
+def run_deferred_async(nursery):
+    for func in deferred_async:
+        nursery.start_soon(func)
+
+
 async def send_push_promise(a, b) -> None:
     pass
 
@@ -45,16 +59,16 @@ async def run_on_pseudo_request(func: Callable, *args):
         nursery.start_soon(run)
 
 
-invoice_listeners: List[Tuple[str, Callable[[Payment], Awaitable[None]]]] = []
+invoice_listeners: List[trio.MemorySendChannel] = []
 
 
-def register_invoice_listener(ext_name: str, cb: Callable[[Payment], Awaitable[None]]):
+def register_invoice_listener(send_chan: trio.MemorySendChannel):
     """
     A method intended for extensions to call when they want to be notified about
     new invoice payments incoming.
     """
-    print(f"registering {ext_name} invoice_listener callback: {cb}")
-    invoice_listeners.append((ext_name, cb))
+    print(f"registering invoice_listener: {send_chan}")
+    invoice_listeners.append(send_chan)
 
 
 async def webhook_handler():
@@ -73,9 +87,5 @@ async def invoice_callback_dispatcher(checking_id: str):
     payment = get_standalone_payment(checking_id)
     if payment and payment.is_in:
         payment.set_pending(False)
-        for ext_name, cb in invoice_listeners:
-            if ext_name == "core":
-                await cb(payment)
-            else:
-                with open_ext_db(ext_name) as g.ext_db:  # type: ignore
-                    await cb(payment)
+        for send_chan in invoice_listeners:
+            await send_chan.send(payment)