Shipping Labels: Optimize country syncing requests

RELEASE-NOTES.txt

@@ -9,6 +9,7 @@
 - [*] Shipping Labels: Enable the confirm button on the payment method sheet even when there are no changes. [https://github.com/woocommerce/woocommerce-ios/pull/15856]
 - [*] POS: start a new cart by scanning a barcode on the payment success screen [https://github.com/woocommerce/woocommerce-ios/pull/15870]
 - [*] Watch app: Fixed connection issue upon fresh install [https://github.com/woocommerce/woocommerce-ios/pull/15867]
+- [Internal] Shipping Labels: Optimize requests for syncing countries [https://github.com/woocommerce/woocommerce-ios/pull/15875]
 - [*] Shipping Labels: Display label size from account settings as default [https://github.com/woocommerce/woocommerce-ios/pull/15873]
 
 22.7

WooCommerce/Classes/ViewRelated/Orders/Order Details/Shipping Labels/WooShipping Create Shipping Labels/ShipmentDetails/WooShippingShipmentDetailsViewModel.swift

@@ -70,7 +70,6 @@ final class WooShippingShipmentDetailsViewModel: ObservableObject {
             order: order,
             shipment: shipment,
             originCountryCode: originCountryCodePublisher(),
-            stores: stores,
             storageManager: storageManager
         ) { [weak self] form in
             self?.customsForm = form

WooCommerce/Classes/ViewRelated/Orders/Order Details/Shipping Labels/WooShipping Create Shipping Labels/WooShipping Customs/WooShippingCustomsFormViewModel.swift

@@ -42,7 +42,6 @@ final class WooShippingCustomsFormViewModel: ObservableObject {
     init(order: Order,
          shipment: Shipment,
          originCountryCode: AnyPublisher<String?, Never>? = nil,
-         stores: StoresManager = ServiceLocator.stores,
          storageManager: StorageManagerType = ServiceLocator.storageManager,
          onFormReady: @escaping (ShippingLabelCustomsForm) -> ()) {
         self.onFormReady = onFormReady
@@ -55,8 +54,7 @@ final class WooShippingCustomsFormViewModel: ObservableObject {
                                             itemWeight: $0.weight,
                                             currencySymbol: currencySymbol(from: order),
                                             originCountryCode: originCountryCode,
-                                            storageManager: storageManager,
-                                            stores: stores)
+                                            storageManager: storageManager)
         }
 
         listenToItemsRequiredInformationValues()

WooCommerce/Classes/ViewRelated/Orders/Order Details/Shipping Labels/WooShipping Create Shipping Labels/WooShipping Customs/WooShippingCustomsItemViewModel.swift

@@ -15,8 +15,6 @@ final class WooShippingCustomsItemViewModel: ObservableObject {
     @Published private var originCountryCode: String?
 
     private let storageManager: StorageManagerType
-    private let stores: StoresManager
-    private let siteID: Int64
     let currencySymbol: String
 
     let itemProductID: Int64
@@ -75,8 +73,7 @@ final class WooShippingCustomsItemViewModel: ObservableObject {
          itemWeight: Double,
          currencySymbol: String,
          originCountryCode: AnyPublisher<String?, Never>? = nil,
-         storageManager: StorageManagerType = ServiceLocator.storageManager,
-         stores: StoresManager = ServiceLocator.stores) {
+         storageManager: StorageManagerType = ServiceLocator.storageManager) {
         self.title = itemName
         self.description = itemName
         self.itemProductID = itemProductID
@@ -85,8 +82,6 @@ final class WooShippingCustomsItemViewModel: ObservableObject {
         self.weightPerUnit = String(itemWeight)
         self.currencySymbol = currencySymbol
         self.storageManager = storageManager
-        self.stores = stores
-        self.siteID = stores.sessionManager.defaultStoreID ?? Int64.min
 
         originCountryCode?
             .assign(to: &$originCountryCode)
@@ -113,21 +108,20 @@ private extension WooShippingCustomsItemViewModel {
     }
 
     func fetchCountries() {
-        try? resultsController.performFetch()
-        countries = resultsController.fetchedObjects
+        resultsController.onDidChangeContent = { [weak self] in
+            self?.updateCountries()
+        }
 
-        let action = DataAction.synchronizeCountries(siteID: siteID) { [weak self] (result) in
-            guard let self = self else { return }
-            switch result {
-            case .success:
-                try? self.resultsController.performFetch()
-                self.countries = self.resultsController.fetchedObjects
-            case .failure:
-                break
-            }
+        resultsController.onDidResetContent = { [weak self] in
+            self?.updateCountries()
         }
 
-        stores.dispatch(action)
+        try? resultsController.performFetch()
+        updateCountries()
+    }
+
+    func updateCountries() {
+        countries = resultsController.fetchedObjects
     }
 
     func combineRequiredInformationIsEntered() {

WooCommerce/Classes/ViewRelated/Orders/Order Details/Shipping Labels/WooShipping Create Shipping Labels/WooShippingAddresses/WooShippingEditAddressViewModel.swift

@@ -628,22 +628,19 @@ private extension WooShippingEditAddressViewModel {
 // MARK: Remote
 private extension WooShippingEditAddressViewModel {
     func fetchCountries() {
-        refreshCountriesAndUpdateSelections()
-        let action = DataAction.synchronizeCountries(siteID: siteID) { [weak self] (result) in
-            guard let self = self else { return }
-            switch result {
-            case .success:
-                refreshCountriesAndUpdateSelections()
-            case .failure:
-                break
-            }
+        resultsController.onDidChangeContent = { [weak self] in
+            self?.refreshCountriesAndUpdateSelections()
+        }
+
+        resultsController.onDidResetContent = { [weak self] in
+            self?.refreshCountriesAndUpdateSelections()
         }
 
-        stores.dispatch(action)
+        try? resultsController.performFetch()
+        refreshCountriesAndUpdateSelections()
     }
 
     func refreshCountriesAndUpdateSelections() {
-        try? resultsController.performFetch()
         // Updating the selected country clears the selected state.
         // We track the initial state code so we can set the correct selected state.
         let stateCode = state.value

WooCommerce/Classes/ViewRelated/Orders/Order Details/Shipping Labels/WooShipping Create Shipping Labels/WooShippingCreateLabelsViewModel.swift

@@ -233,6 +233,7 @@ final class WooShippingCreateLabelsViewModel: ObservableObject {
             loadDestinationAddress()
         }
 
+        syncCountries()
         updateShipmentDetailsViewModels()
         observeSelectedOriginAddress()
         observeDestinationAddress()
@@ -467,6 +468,12 @@ private extension WooShippingCreateLabelsViewModel {
         }
         stores.dispatch(action)
     }
+
+    /// Sync countries to update the storage with latest data from remote.
+    /// This is useful for checking countries in the customs form and listing countries in the edit address form.
+    func syncCountries() {
+        stores.dispatch(DataAction.synchronizeCountries(siteID: order.siteID) { _ in })
+    }
 }
 
 // MARK: Utils

WooCommerce/WooCommerceTests/ViewRelated/Shipping Label/WooShipping Create Shipping Labels/WooShippingEditAddressViewModelTests.swift

@@ -356,18 +356,11 @@ final class WooShippingEditAddressViewModelTests: XCTestCase {
         XCTAssertEqual(viewModel.countries.count, 2, "Should include all countries for destination addresses")
     }
 
-    func test_init_fetches_countries_from_remote() {
+    func test_init_fetches_countries_from_storage() {
         // Given
-        let stores = MockStoresManager(sessionManager: .testingInstance)
         let storageManager = MockStorageManager()
         let country = Country(code: "US", name: "United States", states: [])
-        stores.whenReceivingAction(ofType: DataAction.self) { action in
-            switch action {
-            case .synchronizeCountries(_, let completion):
-                storageManager.insertSampleCountries(readOnlyCountries: [country])
-                completion(.success([country]))
-            }
-        }
+        storageManager.insertSampleCountries(readOnlyCountries: [country])
 
         // When
         let viewModel = WooShippingEditAddressViewModel(type: .destination(orderID: sampleOrderID),
@@ -384,12 +377,10 @@ final class WooShippingEditAddressViewModelTests: XCTestCase {
                                                         isDefaultAddress: true,
                                                         showCompanyField: true,
                                                         isVerified: true,
-                                                        stores: stores,
                                                         storageManager: storageManager)
 
         // Then
         XCTAssertEqual(viewModel.countries.count, 1)
-        XCTAssertTrue(stores.receivedActions.first is DataAction)
     }
 
     func test_state_required_when_selected_country_contains_states() {

WooCommerce/WooCommerceTests/ViewRelated/Shipping Label/WooShipping Create Shipping Labels/WooShippingShipmentDetailsViewModelTests.swift

@@ -359,14 +359,7 @@ final class WooShippingShipmentDetailsViewModelTests: XCTestCase {
             Country(code: "US", name: "United States", states: []),
             Country(code: "CA", name: "Canada", states: [])
         ]
-
-        stores.whenReceivingAction(ofType: DataAction.self) { action in
-            switch action {
-            case let .synchronizeCountries(_, onCompletion):
-                storageManager.insertSampleCountries(readOnlyCountries: countries)
-                onCompletion(.success(countries))
-            }
-        }
+        storageManager.insertSampleCountries(readOnlyCountries: countries)
 
         let originAddressSubject = CurrentValueSubject<WooShippingAddress?, Never>(
             sampleOriginAddress(country: "US", state: "NY")
@@ -790,14 +783,7 @@ final class WooShippingShipmentDetailsViewModelTests: XCTestCase {
             Country(code: "US", name: "United States", states: []),
             Country(code: "CA", name: "Canada", states: [])
         ]
-
-        stores.whenReceivingAction(ofType: DataAction.self) { action in
-            switch action {
-            case let .synchronizeCountries(_, onCompletion):
-                storageManager.insertSampleCountries(readOnlyCountries: countries)
-                onCompletion(.success(countries))
-            }
-        }
+        storageManager.insertSampleCountries(readOnlyCountries: countries)
 
         let viewModel = WooShippingShipmentDetailsViewModel(
             order: Order.fake(),
@@ -833,14 +819,7 @@ final class WooShippingShipmentDetailsViewModelTests: XCTestCase {
             originCountry,
             destinationCountry
         ]
-
-        stores.whenReceivingAction(ofType: DataAction.self) { action in
-            switch action {
-            case let .synchronizeCountries(_, onCompletion):
-                storageManager.insertSampleCountries(readOnlyCountries: countries)
-                onCompletion(.success(countries))
-            }
-        }
+        storageManager.insertSampleCountries(readOnlyCountries: countries)
 
         let shipment = sampleShipment