convert email creation to async

apple/OmnivoreKit/Sources/App/Views/Profile/NewsletterEmailsView.swift

@@ -4,8 +4,7 @@ import Services
 import SwiftUI
 import Views
 
-final class NewsletterEmailsViewModel: ObservableObject {
-  private var hasLoadedInitialEmails = false
+@MainActor final class NewsletterEmailsViewModel: ObservableObject {
   @Published var isLoading = false
   @Published var emails = [NewsletterEmail]()
 
@@ -21,29 +20,23 @@ final class NewsletterEmailsViewModel: ObservableObject {
         dataService.viewContext.perform {
           self?.emails = objectIDs.compactMap { dataService.viewContext.object(with: $0) as? NewsletterEmail }
         }
-        self?.hasLoadedInitialEmails = true
       }
     )
     .store(in: &subscriptions)
   }
 
-  func createEmail(dataService: DataService) {
+  func createEmail(dataService: DataService) async {
     isLoading = true
 
-    dataService.createNewsletterEmailPublisher().sink(
-      receiveCompletion: { [weak self] _ in
-        self?.isLoading = false
-      },
-      receiveValue: { [weak self] objectID in
-        self?.isLoading = false
-        dataService.viewContext.perform {
-          if let item = dataService.viewContext.object(with: objectID) as? NewsletterEmail {
-            self?.emails.insert(item, at: 0)
-          }
+    if let objectID = try? await dataService.createNewsletter() {
+      await dataService.viewContext.perform { [weak self] in
+        if let item = dataService.viewContext.object(with: objectID) as? NewsletterEmail {
+          self?.emails.insert(item, at: 0)
         }
       }
-    )
-    .store(in: &subscriptions)
+    }
+
+    isLoading = false
   }
 }
 
@@ -65,7 +58,7 @@ struct NewsletterEmailsView: View {
         .listStyle(InsetListStyle())
       #endif
     }
-    .onAppear { viewModel.loadEmails(dataService: dataService) }
+    .task { viewModel.loadEmails(dataService: dataService) }
   }
 
   private var innerBody: some View {
@@ -73,7 +66,7 @@ struct NewsletterEmailsView: View {
       Section(footer: Text(footerText)) {
         Button(
           action: {
-            viewModel.createEmail(dataService: dataService)
+            Task { await viewModel.createEmail(dataService: dataService) }
           },
           label: {
             HStack {

apple/OmnivoreKit/Sources/Services/DataService/Mutations/CreateNewsletterEmailMutation.swift

@@ -5,7 +5,7 @@ import Models
 import SwiftGraphQL
 
 public extension DataService {
-  func createNewsletterEmailPublisher() -> AnyPublisher<NSManagedObjectID, BasicError> {
+  func createNewsletter() async throws -> NSManagedObjectID {
     enum MutationResult {
       case saved(newsletterEmail: InternalNewsletterEmail)
       case error(errorCode: Enums.CreateNewsletterEmailErrorCode)
@@ -34,32 +34,24 @@ public extension DataService {
     let path = appEnvironment.graphqlPath
     let headers = networker.defaultHeaders
 
-    return Deferred {
-      Future { promise in
-        send(mutation, to: path, headers: headers) { result in
-          switch result {
-          case let .success(payload):
-            if let graphqlError = payload.errors {
-              promise(.failure(.message(messageText: "graphql error: \(graphqlError)")))
-            }
+    return try await withCheckedThrowingContinuation { continuation in
+      send(mutation, to: path, headers: headers) { [weak self] queryResult in
+        guard let payload = try? queryResult.get(), let self = self else {
+          continuation.resume(throwing: BasicError.message(messageText: "network error"))
+          return
+        }
 
-            switch payload.data {
-            case let .saved(newsletterEmail: newsletterEmail):
-              if let newsletterEmailObjectID = newsletterEmail.persist(context: self.backgroundContext) {
-                promise(.success(newsletterEmailObjectID))
-              } else {
-                promise(.failure(.message(messageText: "coredata error")))
-              }
-            case let .error(errorCode: errorCode):
-              promise(.failure(.message(messageText: errorCode.rawValue)))
-            }
-          case .failure:
-            promise(.failure(.message(messageText: "graphql error")))
+        switch payload.data {
+        case let .saved(newsletterEmail: newsletterEmail):
+          if let newsletterEmailObjectID = newsletterEmail.persist(context: self.backgroundContext) {
+            continuation.resume(returning: newsletterEmailObjectID)
+          } else {
+            continuation.resume(throwing: BasicError.message(messageText: "CoreData error"))
           }
+        case let .error(errorCode: errorCode):
+          continuation.resume(throwing: BasicError.message(messageText: errorCode.rawValue))
         }
       }
     }
-    .receive(on: DispatchQueue.main)
-    .eraseToAnyPublisher()
   }
 }

apple/OmnivoreKit/Sources/Services/InternalModels/InternalNewsletterEmail.swift

@@ -27,7 +27,9 @@ struct InternalNewsletterEmail {
   }
 
   func asManagedObject(inContext context: NSManagedObjectContext) -> NewsletterEmail {
-    let newsletterEmail = NewsletterEmail(entity: NewsletterEmail.entity(), insertInto: context)
+    let existingEmail = NewsletterEmail.lookup(byID: emailId, inContext: context)
+    let newsletterEmail = existingEmail ?? NewsletterEmail(entity: NewsletterEmail.entity(), insertInto: context)
+
     newsletterEmail.emailId = emailId
     newsletterEmail.email = email
     newsletterEmail.confirmationCode = confirmationCode
@@ -54,3 +56,20 @@ extension Sequence where Element == InternalNewsletterEmail {
     return result
   }
 }
+
+extension NewsletterEmail {
+  static func lookup(byID emailID: String, inContext context: NSManagedObjectContext) -> NewsletterEmail? {
+    let fetchRequest: NSFetchRequest<Models.NewsletterEmail> = NewsletterEmail.fetchRequest()
+    fetchRequest.predicate = NSPredicate(
+      format: "%K == %@", #keyPath(NewsletterEmail.emailId), emailID
+    )
+
+    var email: NewsletterEmail?
+
+    context.performAndWait {
+      email = (try? context.fetch(fetchRequest))?.first
+    }
+
+    return email
+  }
+}