WIP: downloading MP3s

apple/OmnivoreKit/Sources/Services/AudioSession/AudioSession.swift

@@ -61,6 +61,8 @@ public class AudioSession: ObservableObject {
     // Just simulating some loading delay here
     DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(1000)) {
       self.audioUrl = Bundle.main.url(forResource: "speech-sample", withExtension: "mp3")!
+      self.audioUrl = URL(string: "https://storage.googleapis.com/omnivore-demo-files/speech/df31ee24-cd3d-412f-9a7c-e8a0afe2e4cd.mp3")!
+
       if let url = self.audioUrl {
         do {
           try? AVAudioSession.sharedInstance().setCategory(.playback)

apple/OmnivoreKit/Sources/Services/DataService/Public/AudioLoading.swift

@@ -0,0 +1,64 @@
+//
+//  File.swift
+//  
+//
+//  Created by Jackson Harper on 8/17/22.
+//
+
+import Foundation
+
+import CoreData
+import Foundation
+import Models
+import Utils
+
+public extension DataService {
+  func loadAudioData(pageId: String) async throws -> URL? {
+    // pageId
+    guard let url = URL(string: pageURLString) else {
+      throw BasicError.message(messageText: "No PDF URL found")
+    }
+
+    let result: (Data, URLResponse)? = try? await URLSession.shared.data(from: url)
+
+    guard let httpResponse = result?.1 as? HTTPURLResponse, 200 ..< 300 ~= httpResponse.statusCode else {
+      throw BasicError.message(messageText: "pdfFetch failed. no response or bad status code.")
+    }
+
+    guard let data = result?.0 else {
+      throw BasicError.message(messageText: "pdfFetch failed. no data received.")
+    }
+
+    var localPdfURL: URL?
+
+    let tempPath = FileManager.default
+      .urls(for: .cachesDirectory, in: .userDomainMask)[0]
+      .appendingPathComponent(UUID().uuidString + ".pdf")
+
+    try await backgroundContext.perform { [weak self] in
+      let fetchRequest: NSFetchRequest<Models.LinkedItem> = LinkedItem.fetchRequest()
+      fetchRequest.predicate = NSPredicate(format: "%K == %@", #keyPath(LinkedItem.slug), slug)
+
+      let linkedItem = try? self?.backgroundContext.fetch(fetchRequest).first
+      guard let linkedItem = linkedItem else {
+        let errorMessage = "pdfFetch failed. could not find LinkedItem from fetch request"
+        throw BasicError.message(messageText: errorMessage)
+      }
+
+      do {
+        try data.write(to: tempPath)
+        let localPDF = try PDFUtils.moveToLocal(url: tempPath)
+        localPdfURL = PDFUtils.localPdfURL(filename: localPDF)
+        linkedItem.tempPDFURL = nil
+        linkedItem.localPDF = localPDF
+        try self?.backgroundContext.save()
+      } catch {
+        self?.backgroundContext.rollback()
+        let errorMessage = "pdfFetch failed. core data save failed."
+        throw BasicError.message(messageText: errorMessage)
+      }
+    }
+
+    return localPdfURL
+  }
+}