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IceTrae merged 1 commit into from
Jul 23, 2025
Merged

Send more detailed errors to consumers #18

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120 changes: 84 additions & 36 deletions Sources/Nes/Client.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@ public enum ConnectionStatus {

public class Client: NSObject {
public private(set) var connectionStatus = CurrentValueSubject<ConnectionStatus, Never>(.disconnected)

private let subject = PassthroughSubject<PubMessage, NesError>()
private var operationQueue = OperationQueue()
private var urlSession: URLSession!
Expand All @@ -21,7 +21,7 @@ public class Client: NSObject {
private var cancellables: Set<AnyCancellable> = []
private var pendingRequests: Dictionary<NesID, (Result<Data, NesError>) -> Void> = [:]
private var fetchAuth: FetchAuthHeadersFuture? = nil

typealias MessageCallback<Message> = (_ message: Message) -> ()
public typealias FetchAuthHeadersFuture = () -> Future<[String:String], Error>

Expand All @@ -30,7 +30,7 @@ public class Client: NSObject {
urlSession = URLSession(configuration: .default, delegate: self, delegateQueue: operationQueue)
webSocketTask = urlSession.webSocketTask(with: url)
}

deinit {
disconnect()
}
Expand All @@ -41,9 +41,9 @@ public class Client: NSObject {
}

webSocketTask.resume()

connectionStatus.send(.connecting)

return connectionStatus
.first(where: { status in
switch (status) {
Expand All @@ -56,17 +56,17 @@ public class Client: NSObject {
.setFailureType(to: NesError.self)
.timeout(.seconds(30), scheduler: DispatchQueue.main, options: nil) { [self] () in
connectionStatus.send(.disconnected)
return NesError(message: "timed out connecting")
return .timedOut(message: "timed out connecting")
}
.map { _ in
return self
}
.eraseToAnyPublisher()
}

public func disconnect(err: Error? = nil) {
connectionStatus.send(.disconnected)
subject.send(completion: err.map { _ in Subscribers.Completion.failure(NesError(message: err?.localizedDescription ?? "")) } ?? .finished)
subject.send(completion: err.map { Subscribers.Completion.failure(NesError(error: $0)) } ?? .finished)
subscriptions.forEach(unsubscribe)
webSocketTask.cancel(with: .goingAway, reason: nil)
cancellables.forEach { $0.cancel() }
Expand All @@ -85,10 +85,10 @@ public class Client: NSObject {

if case .connected = connectionStatus.value {
webSocketTask.send(.data(data), completionHandler: { _ in

})
}

return subject
.filter { pubMessage in
return pubMessage.path.compare(path, options: .caseInsensitive) == .orderedSame
Expand All @@ -97,10 +97,20 @@ public class Client: NSObject {
let pub = try! JSONDecoder().decode(PubMessageContent<Message>.self, from: pubMessage.content)
return pub.message
}
.mapError { NesError(message: $0.localizedDescription) }
.mapError {
let error = NesError(error: $0)
switch error {
case .connectionAborted, .connectionReset:
self.connectionStatus.send(.disconnected)
default:
break
}

return error
}
.eraseToAnyPublisher()
}

public func request<RequestPayload: Encodable, ResponsePayload: Decodable>(
method: HTTPMethod,
path: String,
Expand All @@ -111,7 +121,7 @@ public class Client: NSObject {
let clientRequest = ClientRequest(method: method, path: path, payload: payload, headers: headers)
return request(clientRequest, for: type)
}

public func request<ResponsePayload: Decodable>(
method: HTTPMethod,
path: String,
Expand All @@ -121,7 +131,7 @@ public class Client: NSObject {
let clientRequest = ClientRequest(method: method, path: path, headers: headers)
return request(clientRequest, for: type)
}

func request<RequestPayload: Encodable, ResponsePayload: Decodable>(
_ clientRequest: ClientRequest<RequestPayload>,
for type: ResponsePayload.Type
Expand All @@ -131,17 +141,24 @@ public class Client: NSObject {
return Future<Data, NesError> { [self] promise in
pendingRequests[clientRequest.id] = promise
}
.map { requestResponse in
let response = try! JSONDecoder().decode(RequestResponse<ResponsePayload>.self, from: requestResponse)
return response.payload
.tryMap { requestResponse in
do {
let response = try JSONDecoder().decode(RequestResponse<ResponsePayload>.self, from: requestResponse)
return response.payload
} catch {
throw NesError.decodingFailed(message: error.localizedDescription)
}
}
.mapError { error -> NesError in
(error as? NesError) ?? NesError(error: error)
}
.timeout(.seconds(30), scheduler: DispatchQueue.main, options: nil) { [self] () in
pendingRequests.removeValue(forKey: clientRequest.id)
return NesError(message: "Timed out waiting for response")
return .timedOut(message: "Timed out waiting for response")
}
.eraseToAnyPublisher()
}

public func unsubscribe(_ path: String) {
let id = NesID(string: UUID().uuidString)
let outgoingMessage = ClientUnsub(id: id, path: path)
Expand All @@ -150,13 +167,22 @@ public class Client: NSObject {
subscriptions.remove(path)
webSocketTask.send(.data(data)) { _ in }
}

func readNextMessage() {
webSocketTask.receive { result in
switch(result) {
case .failure(let error):
self.subject.send(completion: .failure(NesError(message: error.localizedDescription)))
let nesError = NesError(error: error)
switch nesError {
case .connectionAborted, .connectionReset:
self.connectionStatus.send(.disconnected)
default:
break
}

self.subject.send(completion: .failure(NesError(error: nesError)))
case .success(.data(let data)):
let string = String(data: data, encoding: .utf8)!
self.parseData(data)
self.readNextMessage()
case .success(.string(let string)):
Expand All @@ -167,15 +193,15 @@ public class Client: NSObject {
}
}
}

func parseData(_ data: Data) {
guard let message = try? JSONDecoder().decode(IncomingMessage.self, from: data) else {
subject.send(completion: .failure(NesError(message: "Error")))
subject.send(completion: .failure(.general(message: "Error")))
return
}

switch message {
case .hello(let hello):
case .hello:
connectionStatus.send(.connected)
case .ping:
let pong = ClientPing(id: NesID(string: UUID().uuidString))
Expand Down Expand Up @@ -206,7 +232,7 @@ public class Client: NSObject {
subscriptions.remove(revoke.path)
}
}

func send<T: OutgoingMessage>(message: T) {
let data = try! JSONEncoder().encode(message)
let message = URLSessionWebSocketTask.Message.data(data)
Expand All @@ -216,7 +242,7 @@ public class Client: NSObject {
}
}
}

private func authenticate() -> AnyPublisher<AuthHeader?, Error> {
switch self.fetchAuth {
case nil:
Expand All @@ -225,7 +251,7 @@ public class Client: NSObject {
return auth().map { AuthHeader(headers: $0) }.eraseToAnyPublisher()
}
}

func sendHello() {
let id = NesID(string: UUID().uuidString)
let subscriptions = self.subscriptions
Expand All @@ -244,26 +270,26 @@ public class Client: NSObject {
})
.store(in: &cancellables)
}

struct PubMessage {
let path: String
let content: Data

init(path: String, content: String) {
self.path = path
self.content = Data(content.utf8)
}

init(path: String, content: Data) {
self.path = path
self.content = content
}
}

struct PubMessageContent<Message: Decodable>: Decodable {
let message: Message
}

struct RequestResponse<ResponsePayload: Decodable>: Decodable {
let id: NesID
let statusCode: Int
Expand All @@ -276,12 +302,34 @@ extension Client: URLSessionWebSocketDelegate {
public func urlSession(_ session: URLSession, webSocketTask: URLSessionWebSocketTask, didOpenWithProtocol protocol: String?) {
sendHello()
}

public func urlSession(_ session: URLSession, webSocketTask: URLSessionWebSocketTask, didCloseWith closeCode: URLSessionWebSocketTask.CloseCode, reason: Data?) {
connectionStatus.send(.disconnected)
}
}

public struct NesError: Error {
let message: String
public enum NesError: Error {
case connectionAborted(message: String)
case connectionReset(message: String)
case timedOut(message: String)
case decodingFailed(message: String)
case general(message: String)

init(error: Error) {
let nsError = error as NSError
if nsError.domain == NSPOSIXErrorDomain {
switch nsError.code {
case 53:
self = .connectionAborted(message: nsError.localizedDescription)
case 54:
self = .connectionReset(message: nsError.localizedDescription)
case 60:
self = .timedOut(message: nsError.localizedDescription)
default:
self = .general(message: nsError.localizedDescription)
}
} else {
self = .general(message: error.localizedDescription)
}
}
}
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