Limit the calls to Terminal SDK for local mobile reader support to 30 seconds

Author: staskus

WooCommerce/Classes/ViewRelated/Dashboard/Settings/In-Person Payments/CardReaderSupportDeterminer.swift

@@ -16,7 +16,7 @@ final class CardReaderSupportDeterminer: CardReaderSupportDetermining {
     private let configuration: CardPresentPaymentsConfiguration
     private let siteID: Int64
     private var locationManager: CLLocationManager = CLLocationManager()
-    private static var deviceSupportsLocalMobileReader: [Int64: Bool] = [:]
+    private static var deviceSupportsLocalMobileReader: [Int64: ExpiringBool] = [:]
 
     init(siteID: Int64,
          configuration: CardPresentPaymentsConfiguration = CardPresentConfigurationLoader().configuration,
@@ -61,11 +61,10 @@ final class CardReaderSupportDeterminer: CardReaderSupportDetermining {
     @MainActor
     func deviceSupportsLocalMobileReader() async -> Bool {
         /// There may be crashes due to multiple consecutive calls checkDeviceSupport
-        /// Local mobile reader (Tap to Pay) support shouldn't change during the app lifecycle
-        /// Only a change in operating system version can affect it which would require a restart of the app
+        /// Limit the calls to once every 30 seconds and cache the result
         ///
-        if let cachedResult = Self.deviceSupportsLocalMobileReader[siteID] {
-            return cachedResult
+        if let cachedResult = Self.deviceSupportsLocalMobileReader[siteID], !cachedResult.isExpired {
+            return cachedResult.value
         }
 
 
@@ -80,7 +79,7 @@ final class CardReaderSupportDeterminer: CardReaderSupportDetermining {
             stores.dispatch(action)
         }
 
-        Self.deviceSupportsLocalMobileReader[siteID] = deviceSupportsLocalMobileReader
+        Self.deviceSupportsLocalMobileReader[siteID] = ExpiringBool(value: deviceSupportsLocalMobileReader, expirationInSeconds: 30)
         return deviceSupportsLocalMobileReader
     }
 
@@ -97,3 +96,15 @@ final class CardReaderSupportDeterminer: CardReaderSupportDetermining {
         }
     }
 }
+
+// MARK: - Helper for caching local reader device support check
+
+private struct ExpiringBool {
+    let value: Bool
+    let expirationInSeconds: Int
+    private let created = Date()
+
+    var isExpired: Bool {
+        Date().timeIntervalSince(created) > Double(expirationInSeconds)
+    }
+}