add logic to prune signal buffer

Author: silesky

packages/signals/signals/src/core/buffer/index.ts

@@ -40,6 +40,8 @@ export class SignalStore implements SignalPersistentStorage {
       },
     })
     logger.debug('Signals Buffer (indexDB) initialized')
+    // if the signal buffer is too large, delete the oldest signals (e.g, the settings have changed)
+    await this.countAndDeleteOldestIfNeeded(db, this.maxBufferSize, true)
     return db
   }
 
@@ -51,20 +53,31 @@ export class SignalStore implements SignalPersistentStorage {
 
   private async countAndDeleteOldestIfNeeded(
     db: IDBPDatabase<SignalDatabase>,
-    maxItems: number
+    maxItems: number,
+    deleteMultiple = false
   ) {
     const transaction = db.transaction(SignalStore.STORE_NAME, 'readwrite')
     const store = transaction.objectStore(SignalStore.STORE_NAME)
-    const count = await store.count()
+    let count = await store.count()
     if (count >= maxItems) {
       const cursor = await store.openCursor()
       if (cursor) {
-        await cursor.delete()
+        // delete up to maxItems
+        if (deleteMultiple) {
+          while (count >= maxItems) {
+            await cursor.delete()
+            count--
+            await cursor.continue()
+          }
+        } else {
+          await cursor.delete()
+        }
         logger.debug('Deleted item', { count: count - 1, key: cursor.key })
       }
     }
     return await transaction.done
   }
+
   /**
    * Get list of signals from the store, with the newest signals first.
    */