Cjbeery24/mint copy: Invoice checker background tasks (#722)

* #616: Removed blocking call from ledger startup. Instead added it to a background task that repeats every hour.

* make task interval configurable, remember task and cancel it on shutdown

* comments

* add sleep to tests because the background task is async

---------

Co-authored-by: Caleb Beery <cjbeery@gmail.com>

cashu/core/settings.py

@@ -64,6 +64,13 @@ class MintSettings(CashuSettings):
     mint_input_fee_ppk: int = Field(default=0)
     mint_disable_melt_on_error: bool = Field(default=False)
 
+    mint_regular_tasks_interval_seconds: int = Field(
+        default=3600,
+        gt=0,
+        title="Regular tasks interval",
+        description="Interval (in seconds) for running regular tasks like the invoice checker.",
+    )
+
 
 class MintDeprecationFlags(MintSettings):
     mint_inactivate_base64_keysets: bool = Field(default=False)

cashu/mint/ledger.py

@@ -95,6 +95,7 @@ class Ledger(LedgerVerification, LedgerSpendingConditions, LedgerTasks, LedgerFe
         self.db_read: DbReadHelper
         self.locks: Dict[str, asyncio.Lock] = {}  # holds multiprocessing locks
         self.invoice_listener_tasks: List[asyncio.Task] = []
+        self.regular_tasks: List[asyncio.Task] = []
 
         if not seed:
             raise Exception("seed not set")
@@ -132,7 +133,7 @@ class Ledger(LedgerVerification, LedgerSpendingConditions, LedgerTasks, LedgerFe
     async def startup_ledger(self) -> None:
         await self._startup_keysets()
         await self._check_backends()
-        await self._check_pending_proofs_and_melt_quotes()
+        self.regular_tasks.append(asyncio.create_task(self._run_regular_tasks()))
         self.invoice_listener_tasks = await self.dispatch_listeners()
 
     async def _startup_keysets(self) -> None:
@@ -140,6 +141,14 @@ class Ledger(LedgerVerification, LedgerSpendingConditions, LedgerTasks, LedgerFe
         for derivation_path in settings.mint_derivation_path_list:
             await self.activate_keyset(derivation_path=derivation_path)
 
+    async def _run_regular_tasks(self) -> None:
+        try:
+            await self._check_pending_proofs_and_melt_quotes()
+            await asyncio.sleep(settings.mint_regular_tasks_interval_seconds)
+        except Exception as e:
+            logger.error(f"Ledger regular task failed: {e}")
+            await asyncio.sleep(60)
+
     async def _check_backends(self) -> None:
         for method in self.backends:
             for unit in self.backends[method]:
@@ -160,9 +169,14 @@ class Ledger(LedgerVerification, LedgerSpendingConditions, LedgerTasks, LedgerFe
         logger.info(f"Data dir: {settings.cashu_dir}")
 
     async def shutdown_ledger(self) -> None:
+        logger.debug("Disconnecting from database")
         await self.db.engine.dispose()
+        logger.debug("Shutting down invoice listeners")
         for task in self.invoice_listener_tasks:
             task.cancel()
+        logger.debug("Shutting down regular tasks")
+        for task in self.regular_tasks:
+            task.cancel()
 
     async def _check_pending_proofs_and_melt_quotes(self):
         """Startup routine that checks all pending melt quotes and either invalidates

tests/test_mint_init.py

@@ -178,6 +178,9 @@ async def test_startup_fakewallet_pending_quote_success(ledger: Ledger):
     # run startup routinge
     await ledger.startup_ledger()
 
+    # we need to sleep because the startup routine for checking the invoices is async
+    await asyncio.sleep(1)
+
     # expect that no pending tokens are in db anymore
     melt_quotes = await ledger.crud.get_all_melt_quotes_from_pending_proofs(
         db=ledger.db
@@ -204,6 +207,9 @@ async def test_startup_fakewallet_pending_quote_failure(ledger: Ledger):
     # run startup routinge
     await ledger.startup_ledger()
 
+    # we need to sleep because the startup routine for checking the invoices is async
+    await asyncio.sleep(1)
+
     # expect that no pending tokens are in db anymore
     melt_quotes = await ledger.crud.get_all_melt_quotes_from_pending_proofs(
         db=ledger.db
@@ -225,6 +231,9 @@ async def test_startup_fakewallet_pending_quote_pending(ledger: Ledger):
     # run startup routinge
     await ledger.startup_ledger()
 
+    # we need to sleep because the startup routine for checking the invoices is async
+    await asyncio.sleep(1)
+
     # expect that melt quote is still pending
     melt_quotes = await ledger.crud.get_all_melt_quotes_from_pending_proofs(
         db=ledger.db
@@ -247,6 +256,9 @@ async def test_startup_fakewallet_pending_quote_unknown(ledger: Ledger):
     # run startup routinge
     await ledger.startup_ledger()
 
+    # we need to sleep because the startup routine for checking the invoices is async
+    await asyncio.sleep(1)
+
     # expect that melt quote is still pending
     melt_quotes = await ledger.crud.get_all_melt_quotes_from_pending_proofs(
         db=ledger.db