feat: use cached rate from exchange_rate_history_setting (#4001)

Co-authored-by: Vlad Stan <stan.v.vlad@gmail.com>

lnbits/core/tasks.py

@@ -25,6 +25,7 @@ from lnbits.core.services.notifications import (
 )
 from lnbits.db import Filters
 from lnbits.settings import settings
+from lnbits.utils.cache import cache
 from lnbits.utils.exchange_rates import btc_rates
 
 audit_queue: asyncio.Queue[AuditEntry] = asyncio.Queue()
@@ -155,6 +156,11 @@ async def collect_exchange_rates_data() -> None:
                     rates_values = [r[1] for r in rates]
                     lnbits_rate = sum(rates_values) / len(rates_values)
                     rates.append(("LNbits", lnbits_rate))
+                    cache.set(
+                        f"btc-price-{currency}",
+                        lnbits_rate,
+                        expiry=settings.lnbits_exchange_rate_cache_seconds,
+                    )
                 settings.append_exchange_rate_datapoint(dict(rates), max_history_size)
             except Exception as ex:
                 logger.warning(ex)

lnbits/settings.py

@@ -359,7 +359,7 @@ class FeeSettings(LNbitsSettings):
 
 
 class ExchangeProvidersSettings(LNbitsSettings):
-    lnbits_exchange_rate_cache_seconds: int = Field(default=30, ge=0)
+    lnbits_exchange_rate_cache_seconds: int = Field(default=60, ge=0)
     lnbits_exchange_history_size: int = Field(default=60, ge=0)
     lnbits_exchange_history_refresh_interval_seconds: int = Field(default=300, ge=0)