Merge pull request #206 from WalletConnect/async-pair

Add Concurrency

Example/DApp/Connect/ConnectViewController.swift

@@ -98,10 +98,9 @@ class ConnectViewController: UIViewController, UITableViewDataSource, UITableVie
         let blockchains: Set<Blockchain> = [Blockchain("eip155:1")!, Blockchain("eip155:137")!]
         let methods: Set<String> = ["eth_sendTransaction", "personal_sign", "eth_signTypedData"]
         let namespaces: Set<Namespace> = [Namespace(chains: blockchains, methods: methods, events: [])]
-        DispatchQueue.global().async {
-            ClientDelegate.shared.client.connect(namespaces: namespaces, topic: pairingTopic) { [weak self] _ in
-                self?.connectWithExampleWallet()
-            }
+        Task {
+            _ = try await ClientDelegate.shared.client.connect(namespaces: namespaces, topic: pairingTopic)
+            connectWithExampleWallet()
         }
     }
 }

Example/DApp/SelectChain/SelectChainViewController.swift

@@ -38,15 +38,9 @@ class SelectChainViewController: UIViewController, UITableViewDataSource {
         let methods: Set<String> = ["eth_sendTransaction", "personal_sign", "eth_signTypedData"]
         let blockchains: Set<Blockchain> = [Blockchain("eip155:1")!, Blockchain("eip155:137")!]
         let namespaces: Set<Namespace> = [Namespace(chains: blockchains, methods: methods, events: [])]
-        DispatchQueue.global().async { [weak self] in
-            self?.client.connect(namespaces: namespaces) { result in
-                switch result {
-                case .success(let uri):
-                    self?.showConnectScreen(uriString: uri!)
-                case .failure(let error):
-                    print("[PROPOSER] Pairing connect error: \(error)")
-                }
-            }
+        Task {
+            let uri = try await client.connect(namespaces: namespaces)
+            showConnectScreen(uriString: uri!)
         }
     }
 

Example/ExampleApp/SceneDelegate.swift

@@ -17,8 +17,16 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
                   return
               }
         let wcUri = incomingURL.absoluteString.deletingPrefix("https://walletconnect.com/wc?uri=")
-        let client = ((window!.rootViewController as! UINavigationController).viewControllers[0] as! WalletViewController).client
-        try? client.pair(uri: wcUri)
+        let vc = ((window!.rootViewController as! UINavigationController).viewControllers[0] as! WalletViewController)
+        vc.onClientConnected = {
+            Task {
+                do {
+                    try await vc.client.pair(uri: wcUri)
+                } catch {
+                    print(error)
+                }
+            }
+        }
     }
 }
 

Example/ExampleApp/Wallet/WalletViewController.swift

@@ -21,6 +21,7 @@ final class WalletViewController: UIViewController {
     lazy  var account = Signer.privateKey.address.hex(eip55: true)
     var sessionItems: [ActiveSessionItem] = []
     var currentProposal: Session.Proposal?
+    var onClientConnected: (()->())?
 
     private let walletView: WalletView = {
         WalletView()
@@ -94,10 +95,12 @@ final class WalletViewController: UIViewController {
 
     private func pairClient(uri: String) {
         print("[RESPONDER] Pairing to: \(uri)")
-        do {
-            try client.pair(uri: uri)
-        } catch {
-            print("[PROPOSER] Pairing connect error: \(error)")
+        Task {
+            do {
+                try await client.pair(uri: uri)
+            } catch {
+                print("[PROPOSER] Pairing connect error: \(error)")
+            }
         }
     }
 }
@@ -152,7 +155,7 @@ extension WalletViewController: ScannerViewControllerDelegate {
 }
 
 extension WalletViewController: ProposalViewControllerDelegate {
-
+        
     func didApproveSession() {
         print("[RESPONDER] Approving session...")
         let proposal = currentProposal!
@@ -171,6 +174,7 @@ extension WalletViewController: ProposalViewControllerDelegate {
 
 extension WalletViewController: WalletConnectClientDelegate {
     func didConnect() {
+        onClientConnected?()
         print("Client connected")
     }
 

Sources/Relayer/Relayer.swift

@@ -132,7 +132,8 @@ public final class Relayer {
         return request.id
     }
 
-    @discardableResult public func subscribe(topic: String, completion: @escaping (Error?) -> ()) -> Int64 {
+    @available(*, renamed: "subscribe(topic:)")
+    public func subscribe(topic: String, completion: @escaping (Error?) -> ()) {
         logger.debug("waku: Subscribing on Topic: \(topic)")
         let params = RelayJSONRPC.SubscribeParams(topic: topic)
         let request = JSONRPCRequest(method: RelayJSONRPC.Method.subscribe.rawValue, params: params)
@@ -154,11 +155,22 @@ public final class Relayer {
                 self?.concurrentQueue.async(flags: .barrier) {
                     self?.subscriptions[topic] = subscriptionResponse.result
                 }
-                completion(nil)
         }
-        return request.id
     }
 
+    public func subscribe(topic: String) async throws {
+        return try await withCheckedThrowingContinuation { continuation in
+            subscribe(topic: topic) { error in
+                if let error = error {
+                    continuation.resume(throwing: error)
+                    return
+                }
+                continuation.resume(returning: ())
+            }
+        }
+    }
+
+
     @discardableResult public func unsubscribe(topic: String, completion: @escaping ((Error?) -> ())) -> Int64? {
         guard let subscriptionId = subscriptions[topic] else {
             completion(RelyerError.subscriptionIdNotFound)

Sources/WalletConnect/Engine/PairingEngine.swift → Sources/WalletConnect/Engine/Common/PairingEngine.swift

@@ -59,23 +59,19 @@ final class PairingEngine {
             .map {Pairing(topic: $0.topic, peer: $0.peerMetadata, expiryDate: $0.expiryDate)}
     }
 
-    func create() -> WalletConnectURI? {
+    func create() async throws -> WalletConnectURI {
         let topic = topicInitializer()
+        try await networkingInteractor.subscribe(topic: topic)
         let symKey = try! kms.createSymmetricKey(topic)
         let pairing = WCPairing(topic: topic)
         let uri = WalletConnectURI(topic: topic, symKey: symKey.hexRepresentation, relay: pairing.relay)
         pairingStore.setPairing(pairing)
-        networkingInteractor.subscribe(topic: topic)
         return uri
     }
-    func propose(pairingTopic: String, namespaces: Set<Namespace>, relay: RelayProtocolOptions, completion: @escaping ((Error?) -> ())) {
+
+    func propose(pairingTopic: String, namespaces: Set<Namespace>, relay: RelayProtocolOptions) async throws {
         logger.debug("Propose Session on topic: \(pairingTopic)")
-        do {
-            try Namespace.validate(namespaces)
-        } catch {
-            completion(error)
-            return
-        }
+        try Namespace.validate(namespaces)
         let publicKey = try! kms.createX25519KeyPair()
         let proposer = Participant(
             publicKey: publicKey.hexRepresentation,
@@ -84,24 +80,17 @@ final class PairingEngine {
             relays: [relay],
             proposer: proposer,
             namespaces: namespaces)
-        networkingInteractor.requestNetworkAck(.wcSessionPropose(proposal), onTopic: pairingTopic) { [unowned self] error in
-            logger.debug("Received propose acknowledgement from network")
-            completion(error)
-        }
-    }
-
-    func pair(_ uri: WalletConnectURI) throws {
-        guard !hasPairing(for: uri.topic) else {
-            throw WalletConnectError.pairingAlreadyExist
+        return try await withCheckedThrowingContinuation { continuation in
+            networkingInteractor.requestNetworkAck(.wcSessionPropose(proposal), onTopic: pairingTopic) { error in
+                if let error = error {
+                    continuation.resume(throwing: error)
+                } else {
+                    continuation.resume()
+                }
+            }
         }
-        var pairing = WCPairing(uri: uri)
-        let symKey = try! SymmetricKey(hex: uri.symKey) // FIXME: Malformed QR code from external source can crash the SDK
-        try! kms.setSymmetricKey(symKey, for: pairing.topic)
-        pairing.activate()
-        networkingInteractor.subscribe(topic: pairing.topic)
-        pairingStore.setPairing(pairing)
     }
-    
+
     func ping(topic: String, completion: @escaping ((Result<Void, Error>) -> ())) {
         guard pairingStore.hasPairing(forTopic: topic) else {
             logger.debug("Could not find pairing to ping for topic \(topic)")
@@ -186,7 +175,7 @@ final class PairingEngine {
             .sink { [unowned self] (_) in
                 let topics = pairingStore.getAll()
                     .map{$0.topic}
-                topics.forEach{networkingInteractor.subscribe(topic: $0)}
+                topics.forEach{ topic in Task{try? await networkingInteractor.subscribe(topic: topic)}}
             }.store(in: &publishers)
     }
 

Sources/WalletConnect/Engine/SessionEngine.swift → Sources/WalletConnect/Engine/Common/SessionEngine.swift

@@ -48,7 +48,7 @@ final class SessionEngine {
     }
 
     func setSubscription(topic: String) {
-        networkingInteractor.subscribe(topic: topic)
+        Task { try? await networkingInteractor.subscribe(topic: topic) }
     }
 
     func hasSession(for topic: String) -> Bool {
@@ -107,21 +107,16 @@ final class SessionEngine {
         }
     }
 
-    func emit(topic: String, event: SessionType.EventParams.Event, chainId: Blockchain, completion: ((Error?)->())?) {
+    func emit(topic: String, event: SessionType.EventParams.Event, chainId: Blockchain) async throws {
         guard let session = sessionStore.getSession(forTopic: topic), session.acknowledged else {
             logger.debug("Could not find session for topic \(topic)")
             return
         }
         let params = SessionType.EventParams(event: event, chainId: chainId)
-        do {
-            guard session.hasNamespace(for: chainId, event: event.name) else {
-                throw WalletConnectError.invalidEvent
-            }
-            networkingInteractor.request(.wcSessionEvent(params), onTopic: topic)
-        } catch let error as WalletConnectError {
-            logger.error(error)
-            completion?(error)
-        } catch {}
+        guard session.hasNamespace(for: chainId, event: event.name) else {
+            throw WalletConnectError.invalidEvent
+        }
+        try await networkingInteractor.request(.wcSessionEvent(params), onTopic: topic)
     }
 
     //MARK: - Private
@@ -165,9 +160,8 @@ final class SessionEngine {
             settleParams: settleParams,
             acknowledged: false)
         logger.debug("Sending session settle request")
-        networkingInteractor.subscribe(topic: topic)
+        Task { try? await networkingInteractor.subscribe(topic: topic) }
         sessionStore.setSession(session)
-
         networkingInteractor.request(.wcSessionSettle(settleParams), onTopic: topic)
     }
 
@@ -262,7 +256,7 @@ final class SessionEngine {
         networkingInteractor.transportConnectionPublisher
             .sink { [unowned self] (_) in
                 let topics = sessionStore.getAll().map{$0.topic}
-                topics.forEach{networkingInteractor.subscribe(topic: $0)}
+                topics.forEach{ topic in Task { try? await networkingInteractor.subscribe(topic: topic) } }
             }.store(in: &publishers)
     }
 

Sources/WalletConnect/Engine/Controller/PairEngine.swift

@@ -0,0 +1,33 @@
+
+import Foundation
+import WalletConnectKMS
+
+actor PairEngine {
+    private let networkingInteractor: NetworkInteracting
+    private let kms: KeyManagementServiceProtocol
+    private let pairingStore: WCPairingStorage
+
+    init(networkingInteractor: NetworkInteracting,
+         kms: KeyManagementServiceProtocol,
+         pairingStore: WCPairingStorage) {
+        self.networkingInteractor = networkingInteractor
+        self.kms = kms
+        self.pairingStore = pairingStore
+    }
+
+    func pair(_ uri: WalletConnectURI) async throws {
+        guard !hasPairing(for: uri.topic) else {
+            throw WalletConnectError.pairingAlreadyExist
+        }
+        var pairing = WCPairing(uri: uri)
+        try await networkingInteractor.subscribe(topic: pairing.topic)
+        let symKey = try! SymmetricKey(hex: uri.symKey) // FIXME: Malformed QR code from external source can crash the SDK
+        try! kms.setSymmetricKey(symKey, for: pairing.topic)
+        pairing.activate()
+        pairingStore.setPairing(pairing)
+    }
+
+    func hasPairing(for topic: String) -> Bool {
+        return pairingStore.hasPairing(forTopic: topic)
+    }
+}

Sources/WalletConnect/NetworkInteractor/NetworkInteractor.swift

@@ -30,7 +30,7 @@ protocol NetworkInteracting: AnyObject {
     func respond(topic: String, response: JsonRpcResult, completion: @escaping ((Error?)->()))
     func respondSuccess(for payload: WCRequestSubscriptionPayload)
     func respondError(for payload: WCRequestSubscriptionPayload, reason: ReasonCode)
-    func subscribe(topic: String)
+    func subscribe(topic: String) async throws
     func unsubscribe(topic: String)
 }
 
@@ -169,12 +169,8 @@ class NetworkInteractor: NetworkInteracting {
         respond(topic: payload.topic, response: JsonRpcResult.error(response)) { _ in } // TODO: Move error handling to relayer package
     }
 
-    func subscribe(topic: String)  {
-        networkRelayer.subscribe(topic: topic) { [weak self] error in
-            if let error = error {
-                self?.logger.error(error)
-            }
-        }
+    func subscribe(topic: String) async throws {
+        try await networkRelayer.subscribe(topic: topic)
     }
 
     func unsubscribe(topic: String) {

Sources/WalletConnect/NetworkInteractor/NetworkRelaying.swift

@@ -13,8 +13,8 @@ protocol NetworkRelaying {
     func publish(topic: String, payload: String, prompt: Bool) async throws
     /// - returns: request id
     @discardableResult func publish(topic: String, payload: String, prompt: Bool, onNetworkAcknowledge: @escaping ((Error?)->())) -> Int64
-    /// - returns: request id
-    @discardableResult func subscribe(topic: String, completion: @escaping (Error?)->()) -> Int64
+    func subscribe(topic: String, completion: @escaping (Error?)->())
+    func subscribe(topic: String) async throws 
     /// - returns: request id
     @discardableResult func unsubscribe(topic: String, completion: @escaping ((Error?)->())) -> Int64?
 }