Experiment with async/await

Note that URLSession async only works >=iOS 15. I changed the target for
now, but may mess with continuations.

5 files changed, 111 insertions, 33 deletions

diff --git a/foray.xcodeproj/project.pbxproj b/foray.xcodeproj/project.pbxproj
index 3d24015..3901dc6 100644
--- a/foray.xcodeproj/project.pbxproj
+++ b/foray.xcodeproj/project.pbxproj
@@ -371,7 +371,7 @@
 				INFOPLIST_KEY_UIMainStoryboardFile = "";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 15.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -401,7 +401,7 @@
 				INFOPLIST_KEY_UIMainStoryboardFile = "";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 15.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
diff --git a/foray.xcodeproj/xcshareddata/xcschemes/foray.xcscheme b/foray.xcodeproj/xcshareddata/xcschemes/foray.xcscheme
new file mode 100644
index 0000000..09e83ac
--- /dev/null
+++ b/foray.xcodeproj/xcshareddata/xcschemes/foray.xcscheme
@@ -0,0 +1,78 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1340"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "C04B459F27DEF117001451A3"
+               BuildableName = "foray.app"
+               BlueprintName = "foray"
+               ReferencedContainer = "container:foray.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "C04B459F27DEF117001451A3"
+            BuildableName = "foray.app"
+            BlueprintName = "foray"
+            ReferencedContainer = "container:foray.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "C04B459F27DEF117001451A3"
+            BuildableName = "foray.app"
+            BlueprintName = "foray"
+            ReferencedContainer = "container:foray.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>
diff --git a/foray/Fetchers/ForayFetcher.swift b/foray/Fetchers/ForayFetcher.swift
index d8df037..e4c6fd9 100644
--- a/foray/Fetchers/ForayFetcher.swift
+++ b/foray/Fetchers/ForayFetcher.swift
@@ -27,23 +27,18 @@ class ForayFetcher {
         return jd
     }()
     
-    func fetch<T: Decodable>(url: String,
-                             receiver: @escaping (T) -> ()) {
-        // Fetch on a background thread
-        DispatchQueue.global(qos: .background).async {
-            var request = URLRequest(url: URL(string: url)!)
-            request.cachePolicy = .reloadRevalidatingCacheData // Needed otherwise default caching policy seems not to check properly
-            
-            // Basic auth if required
-            if (self.basicUsername != nil && self.basicPassword != nil) {
-                let authData = (self.basicUsername! + ":" + self.basicPassword!).data(using: .utf8)!.base64EncodedString()
-                request.addValue("Basic \(authData)", forHTTPHeaderField: "Authorization")
-            }
+    func fetch<T: Decodable>(url: String) async throws -> T {
+        var request = URLRequest(url: URL(string: url)!)
+        request.cachePolicy = .reloadRevalidatingCacheData // Needed otherwise default caching policy seems not to check properly
 
-            URLSession.shared.dataTask(with: request, completionHandler: { data, response, error -> Void in
-                let items = try! self.jsonDecoder.decode(T.self, from: data!)
-                receiver(items)
-            }).resume()
+        // Basic auth if required
+        if (self.basicUsername != nil && self.basicPassword != nil) {
+            let authData = (self.basicUsername! + ":" + self.basicPassword!).data(using: .utf8)!.base64EncodedString()
+            request.addValue("Basic \(authData)", forHTTPHeaderField: "Authorization")
         }
+
+        let (data, _) = try await URLSession.shared.data(for: request)
+        let items = try jsonDecoder.decode(T.self, from: data)
+        return items
     }
 }
diff --git a/foray/Presenters/PenguinItemPresenter.swift b/foray/Presenters/PenguinItemPresenter.swift
index c4553ae..1d617bf 100644
--- a/foray/Presenters/PenguinItemPresenter.swift
+++ b/foray/Presenters/PenguinItemPresenter.swift
@@ -8,18 +8,19 @@
 import Foundation
 
 class PenguinItemPresenter {
+
+    private struct Constants {
+        static let apiEndpoint = "https://users.windblume.net/~nick/upload/dummy.json"
+    }
     
     let fetcher = ForayFetcher()
     
-    func fetch(receiver: @escaping ([PenguinItemViewModel]) -> ()) {
-        fetcher.fetch(url: "https://users.windblume.net/~nick/upload/dummy.json") { [weak self] (apiItems: [PenguinItemModel]) in
-            // Callback to main thread here
-            // There probably is a nicer way to do it, but we will DispatchQueue it back
-            // from the Presenter-level for now (main thread from VC onwards)
-            DispatchQueue.main.async {
-                guard let self = self else { return }
-                receiver(self.transform(models: apiItems))
-            }
+    func fetch() async -> [PenguinItemViewModel] {
+        do {
+            let apiItems: [PenguinItemModel] = try await fetcher.fetch(url: Constants.apiEndpoint)
+            return transform(models: apiItems)
+        } catch {
+            return []
         }
     }
     
diff --git a/foray/Scenes/ForayTableViewController.swift b/foray/Scenes/ForayTableViewController.swift
index a29088c..849553c 100644
--- a/foray/Scenes/ForayTableViewController.swift
+++ b/foray/Scenes/ForayTableViewController.swift
@@ -42,21 +42,25 @@ class ForayTableViewController: UITableViewController, Coordinated {
         self.refreshControl?.addTarget(self, action: #selector(doRefresh), for: UIControl.Event.valueChanged)
     }
     
-    @objc func doRefresh(sender: AnyObject) {
+    @objc
+    func doRefresh(sender: AnyObject) {
         reloadApiData()
     }
     
     func reloadApiData() {
-        presenter.fetch { [weak self] (data: [PenguinItemViewModel]) in
-            guard let self = self else { return }
-            
-            let groups = Dictionary(grouping: data) { $0.year }
+        Task(priority: .medium) { [weak self] in
+            let models = await self?.presenter.fetch()
+
+            guard let self = self,
+                  let models = models else { return }
+
+            let groups = Dictionary(grouping: models) { $0.year }
             self.sections = groups.map { (key, values) in
                 return YearSection(year: key, items: values)
             }
             // Sort the sections from oldest year to newest
             self.sections.sort { (lhs, rhs) in lhs.year < rhs.year }
-            
+
             self.tableView.reloadData()
             self.refreshControl?.endRefreshing()
             self.coordinator?.hideLoading()