Stmol · December 26, 2021 15:01 · Dec 20, 2021 · Dec 20, 2021
diff --git a/ContentView.swift → ExportView.swift b/ContentView.swift → ExportView.swift
@@ -31,7 +31,7 @@ struct IPAFile: FileDocument
     }
 }
 
-struct ContentView: View 
+struct ExportView: View 
 {
     @State 
     private var isExporting = false

diff --git a/ContentView.swift b/ContentView.swift
@@ -0,0 +1,72 @@
+// Example exportIPA() usage
+
+import SwiftUI
+import UniformTypeIdentifiers
+
+extension UTType
+{
+    static let ipa = UTType(filenameExtension: "ipa")!
+}
+
+struct IPAFile: FileDocument
+{
+    let file: FileWrapper
+
+    static var readableContentTypes: [UTType] { [.ipa] }
+    static var writableContentTypes: [UTType] { [.ipa] }
+
+    init(ipaURL: URL) throws
+    {
+        self.file = try FileWrapper(url: ipaURL, options: .immediate)
+    }
+
+    init(configuration: ReadConfiguration) throws 
+    {
+        self.file = configuration.file
+    }
+
+    func fileWrapper(configuration: WriteConfiguration) throws -> FileWrapper 
+    {
+        return self.file
+    }
+}
+
+struct ContentView: View 
+{
+    @State 
+    private var isExporting = false
+
+    @State
+    private var ipaFile: IPAFile?
+
+    var body: some View {
+        VStack(spacing: 25) {
+            Button(action: export) { 
+                Label("Export IPA", systemImage: "square.and.arrow.up")
+                    .imageScale(.large)
+                    .foregroundColor(.accentColor)
+            }
+        }
+        .fileExporter(isPresented: self.$isExporting, document: self.ipaFile, contentType: .ipa) { result in
+            print("Exported IPA:", result)
+        }
+    }
+
+    private func export()
+    {
+        Task { @MainActor in            
+            do
+            {
+                let ipaPath = try await exportIPA()
+                let ipaURL = URL(fileURLWithPath: ipaPath)
+
+                self.ipaFile = try IPAFile(ipaURL: ipaURL)
+                self.isExporting = true
+            }
+            catch
+            {
+                print("Could not export .ipa:", error)
+            }
+        }
+    }
+}
diff --git a/ExportIPA.swift b/ExportIPA.swift
@@ -0,0 +1,63 @@
+import Foundation
+
+// Export running app as .ipa, then return path to exported file.
+// Returns String because app crashes when returning URL from async function for some reason...
+func exportIPA() async throws -> String
+{
+    // Path to app bundle
+    let bundleURL = Bundle.main.bundleURL
+
+    // Create Payload/ directory
+    let temporaryDirectory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
+    let payloadDirectory = temporaryDirectory.appendingPathComponent("Payload")
+    try FileManager.default.createDirectory(at: payloadDirectory, withIntermediateDirectories: true, attributes: nil)
+
+    defer {
+        // Remove temporary directory
+        try? FileManager.default.removeItem(at: temporaryDirectory)
+    }
+
+    let appName = Bundle.main.object(forInfoDictionaryKey: kCFBundleNameKey as String) as? String ?? "App"
+    let appURL = payloadDirectory.appendingPathComponent("\(appName).app")
+    let ipaURL = FileManager.default.temporaryDirectory.appendingPathComponent("\(appName).ipa")
+
+    // Copy app bundle to Payload/
+    try FileManager.default.copyItem(at: bundleURL, to: appURL)
+
+    // Remove occurrences of "swift-playgrounds-" from bundle identifier.
+    // (Apple forbids registering App IDs containing that string)
+    let bundleID = Bundle.main.bundleIdentifier!
+    let updatedBundleID = bundleID.replacingOccurrences(of: "swift-playgrounds-", with: "")
+
+    // Update bundle identifier
+    let plistURL = appURL.appendingPathComponent("Info.plist")
+    let infoPlist = try NSMutableDictionary(contentsOf: plistURL, error: ())
+    infoPlist[kCFBundleIdentifierKey as String] = updatedBundleID
+    try infoPlist.write(to: plistURL) 
+
+    try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<Void, Error>) in
+        // Coordinating read access to Payload/ "forUploading" automatically zips the directory for us.
+        let readIntent = NSFileAccessIntent.readingIntent(with: payloadDirectory, options: .forUploading)
+
+        let fileCoordinator = NSFileCoordinator()
+        fileCoordinator.coordinate(with: [readIntent], queue: .main) { error in
+            do
+            {
+                guard error == nil else { throw error! }
+
+                // Change file extension from "zip" to "ipa"
+                _ = try FileManager.default.replaceItemAt(ipaURL, withItemAt: readIntent.url)
+
+                print("Exported .ipa:", ipaURL)
+                continuation.resume()
+            }
+            catch
+            {
+                print("Failed to export .ipa:", error)
+                continuation.resume(throwing: error)
+            }
+        }
+    }
+
+    return ipaURL.path
+}