Merge branch 'transport-api-requests-across-apppacket-tunnel-boundary-ios-1041'

1 files changed, 89 insertions, 0 deletions

diff --git a/ios/MullvadREST/APIRequest/APIRequestProxy.swift b/ios/MullvadREST/APIRequest/APIRequestProxy.swift
new file mode 100644
index 0000000000..8e2ac4fad2
--- /dev/null
+++ b/ios/MullvadREST/APIRequest/APIRequestProxy.swift
@@ -0,0 +1,89 @@
+//
+//  APIRequestProxy.swift
+//  MullvadVPN
+//
+//  Created by Jon Petersson on 2025-02-13.
+//  Copyright © 2025 Mullvad VPN AB. All rights reserved.
+//
+
+import MullvadRustRuntime
+import MullvadTypes
+
+public protocol APIRequestProxyProtocol {
+    func sendRequest(_ proxyRequest: ProxyAPIRequest, completion: @escaping @Sendable (ProxyAPIResponse) -> Void)
+    func sendRequest(_ proxyRequest: ProxyAPIRequest) async -> ProxyAPIResponse
+    func cancelRequest(identifier: UUID)
+}
+
+/// Network request proxy capable of passing serializable requests and responses over the given transport provider.
+public final class APIRequestProxy: APIRequestProxyProtocol, @unchecked Sendable {
+    /// Serial queue used for synchronizing access to class members.
+    private let dispatchQueue: DispatchQueue
+
+    private let transportProvider: APITransportProviderProtocol
+
+    /// List of all proxied network requests bypassing VPN.
+    private var proxiedRequests: [UUID: Cancellable] = [:]
+
+    public init(
+        dispatchQueue: DispatchQueue,
+        transportProvider: APITransportProviderProtocol
+    ) {
+        self.dispatchQueue = dispatchQueue
+        self.transportProvider = transportProvider
+    }
+
+    public func sendRequest(
+        _ proxyRequest: ProxyAPIRequest,
+        completion: @escaping @Sendable (ProxyAPIResponse) -> Void
+    ) {
+        dispatchQueue.async {
+            guard let transport = self.transportProvider.makeTransport() else {
+                // Cancel old task, if there's one scheduled.
+                self.cancelRequest(identifier: proxyRequest.id)
+
+                completion(ProxyAPIResponse(data: nil, error: nil))
+                return
+            }
+
+            let cancellable = transport.sendRequest(proxyRequest.request) { [weak self] response in
+                guard let self else { return }
+
+                // Use `dispatchQueue` to guarantee thread safe access to `proxiedRequests`
+                dispatchQueue.async {
+                    _ = self.removeRequest(identifier: proxyRequest.id)
+                    completion(response)
+                }
+            }
+
+            // Cancel old task, if there's one scheduled.
+            let oldTask = self.addRequest(identifier: proxyRequest.id, task: cancellable)
+            oldTask?.cancel()
+        }
+    }
+
+    public func sendRequest(_ proxyRequest: ProxyAPIRequest) async -> ProxyAPIResponse {
+        return await withCheckedContinuation { continuation in
+            sendRequest(proxyRequest) { proxyResponse in
+                continuation.resume(returning: proxyResponse)
+            }
+        }
+    }
+
+    public func cancelRequest(identifier: UUID) {
+        dispatchQueue.async {
+            let task = self.removeRequest(identifier: identifier)
+            task?.cancel()
+        }
+    }
+
+    private func addRequest(identifier: UUID, task: Cancellable) -> Cancellable? {
+        dispatchPrecondition(condition: .onQueue(dispatchQueue))
+        return proxiedRequests.updateValue(task, forKey: identifier)
+    }
+
+    private func removeRequest(identifier: UUID) -> Cancellable? {
+        dispatchPrecondition(condition: .onQueue(dispatchQueue))
+        return proxiedRequests.removeValue(forKey: identifier)
+    }
+}