Add a retry mechanism

Author: Fernando Fernandes

Sources/SwiftTrader/Model/Kucoin/KucoinFuturesAccountOverviewResponse.swift renamed to Sources/SwiftTrader/Model/Kucoin/KucoinFuturesAccountOverview.swift

@@ -1,5 +1,5 @@
 //
-//  KucoinFuturesAccountOverviewResponse.swift
+//  KucoinFuturesAccountOverview.swift
 //  
 //
 //  Created by Fernando Fernandes on 27.01.22.
@@ -10,7 +10,7 @@ import Foundation
 /// Kucoin "Get Account Overview" REST API response.
 ///
 /// https://docs.kucoin.com/futures/#account
-public struct KucoinFuturesAccountOverviewResponse: Codable {
+public struct KucoinFuturesAccountOverview: Codable {
     public let code: String
     public let data: KucoinFuturesAccountData
 }

Sources/SwiftTrader/Network/Kucoin/AccountOverview/KucoinAccountOverviewRequest.swift renamed to Sources/SwiftTrader/Network/Kucoin/AccountOverview/KucoinFuturesAccountOverviewRequest.swift

@@ -1,5 +1,5 @@
 //
-//  KucoinAccountOverviewRequest.swift
+//  KucoinFuturesAccountOverviewRequest.swift
 //  
 //
 //  Created by Fernando Fernandes on 29.01.22.
@@ -13,24 +13,27 @@ import FoundationNetworking
 /// A **request** for an overview of a Kucoin Futures account.
 ///
 /// https://docs.kucoin.com/futures/#account
-public struct KucoinAccountOverviewRequest: NetworkRequest {
+public struct KucoinFuturesAccountOverviewRequest: NetworkRequest {
 
     // MARK: - Properties
 
-    public typealias DecodableModel = KucoinFuturesAccountOverviewResponse
+    public typealias DecodableModel = KucoinFuturesAccountOverview
 
     public var session: URLSession
 
     public var request: URLRequest {
         get throws {
-            let accountOverviewResource = KucoinAccountOverviewResource(currencySymbol: currencySymbol)
-            var urlRequest = URLRequest(url: try accountOverviewResource.url)
+            let futuresAccountOverviewResource = KucoinFuturesAccountOverviewResource(currencySymbol: currencySymbol)
+            var urlRequest = URLRequest(url: try futuresAccountOverviewResource.url)
             urlRequest.httpMethod = HTTPMethod.GET.rawValue
             try KucoinAPI.setRequestHeaderFields(request: &urlRequest, kucoinAuth: kucoinAuth)
             return urlRequest
         }
     }
 
+    #warning("TODO: [CONFIG] number of retries")
+    public var numberOfRetries: Int { 3 }
+    
     // MARK: Private
 
     private let currencySymbol: CurrencySymbol
@@ -39,7 +42,7 @@ public struct KucoinAccountOverviewRequest: NetworkRequest {
 
     // MARK: - Lifecycle
 
-    /// Creates a new `KucoinAccountOverviewRequest` instance.
+    /// Creates a new `KucoinFuturesAccountOverviewRequest` instance.
     ///
     /// - Parameter session: `URLSession` instance, the default is `.shared`.
     public init(session: URLSession = .shared, currencySymbol: CurrencySymbol = .USDT, kucoinAuth: KucoinAuth) {
@@ -51,9 +54,9 @@ public struct KucoinAccountOverviewRequest: NetworkRequest {
 
 // MARK: - Network Request Protocol
 
-public extension KucoinAccountOverviewRequest {
+public extension KucoinFuturesAccountOverviewRequest {
 
     func decode(_ data: Data) throws -> DecodableModel {
-        try JSONDecoder().decode(KucoinFuturesAccountOverviewResponse.self, from: data)
+        try JSONDecoder().decode(KucoinFuturesAccountOverview.self, from: data)
     }
 }

Sources/SwiftTrader/Network/Kucoin/AccountOverview/KucoinAccountOverviewResource.swift renamed to Sources/SwiftTrader/Network/Kucoin/AccountOverview/KucoinFuturesAccountOverviewResource.swift

@@ -1,5 +1,5 @@
 //
-//  KucoinAccountOverviewResource.swift
+//  KucoinFuturesAccountOverviewResource.swift
 //  
 //
 //  Created by Fernando Fernandes on 29.01.22.
@@ -10,7 +10,7 @@ import Foundation
 /// The **resource** for requesting an overview of a Kucoin Futures account.
 ///
 /// https://docs.kucoin.com/futures/#account
-public struct KucoinAccountOverviewResource: NetworkResource {
+public struct KucoinFuturesAccountOverviewResource: NetworkResource {
 
     // MARK: - Properties
 
@@ -38,7 +38,7 @@ public struct KucoinAccountOverviewResource: NetworkResource {
 
     // MARK: - Lifecycle
 
-    /// Creates a new `KucoinAccountOverviewResource` instance.
+    /// Creates a new `KucoinFuturesAccountOverviewResource` instance.
     ///
     /// - Parameter currencySymbol: `CurrencySymbol`, default is `USDT`.
     init(currencySymbol: CurrencySymbol = .USDT) {

Sources/SwiftTrader/Network/NetworkRequest/NetworkRequestProtocol+Execution.swift

@@ -21,27 +21,41 @@ public extension NetworkRequest {
     ///
     /// - Parameter request: `URLRequest` containing the target `URL`.
     /// - Returns: `NetworkRequestResult`.
-    func execute() async -> NetworkRequestResult {
+    func execute(attemptNumber: Int = 1) async -> NetworkRequestResult {
         let req: URLRequest
         do {
             req = try request
         } catch {
             return .failure(.invalidRequest(error: error))
         }
 #if os(macOS) || os(iOS)
-        return await runOnApplePlatforms(request: req)
+        let result = await runOnApplePlatforms(request: req)
+        switch result {
+        case .success:
+            return result
+        case .failure:
+            if attemptNumber <= numberOfRetries {
+#warning("TODO: [CONFIG] Wait time between attempts")
+                let seconds: Double = 2
+                await Task.sleep(UInt64(seconds * Double(NSEC_PER_SEC)))
+#warning("TODO: logger")
+                print("Retrying... \(attemptNumber) of \(numberOfRetries)")
+                fflush(stdout)
+                return await execute(attemptNumber: attemptNumber + 1)
+            } else {
+                return result
+            }
+        }
 #elseif canImport(FoundationNetworking)
         return await runOnLinux(request: req)
 #endif
     }
 }
 
-#warning("TODO: retry mechanism, at least 3 times")
-
 // MARK: - Private
 
 private extension NetworkRequest {
-
+    
 #if os(macOS) || os(iOS)
     /// macOS and iOS.
     func runOnApplePlatforms(request: URLRequest) async -> NetworkRequestResult {
@@ -53,7 +67,7 @@ private extension NetworkRequest {
         }
     }
 #endif
-
+    
     /// `async/await` isn't fully ported to Linux; use "withCheckedContinuation(function:_:)" instead.
     func runOnLinux(request: URLRequest) async -> NetworkRequestResult {
         let (data, response, error) = await withCheckedContinuation { continuation in

Sources/SwiftTrader/Network/NetworkRequest/NetworkRequestProtocol.swift

@@ -17,6 +17,7 @@ public protocol NetworkRequest {
     associatedtype DecodableModel: Decodable
     var session: URLSession { get }
     var request: URLRequest { get throws }
-    func execute() async -> NetworkRequestResult
+    var numberOfRetries: Int { get }
+    func execute(attemptNumber: Int) async -> NetworkRequestResult
     func decode(_ data: Data) throws -> DecodableModel
 }

Sources/SwiftTrader/SwiftTrader.swift

@@ -25,14 +25,14 @@ public struct SwiftTrader {
 
 public extension SwiftTrader {
 
-    func kucoinFuturesAccountOverview() async throws -> Result<KucoinFuturesAccountOverviewResponse, SwiftTraderError> {
-        let request = KucoinAccountOverviewRequest(kucoinAuth: kucoinAuth)
+    func kucoinFuturesAccountOverview(currencySymbol: CurrencySymbol = .USDT) async throws -> Result<KucoinFuturesAccountOverview, SwiftTraderError> {
+        let request = KucoinFuturesAccountOverviewRequest(currencySymbol: currencySymbol, kucoinAuth: kucoinAuth)
         switch await request.execute() {
         case .success(let model):
-            guard let accountOverview = model as? KucoinFuturesAccountOverviewResponse else {
+            guard let futuresAccountOverview = model as? KucoinFuturesAccountOverview else {
                 return .failure(.unexpectedResponse(modelString: "\(model)"))
             }
-            return .success(accountOverview)
+            return .success(futuresAccountOverview)
         case .failure(let error):
             switch error {
             case .statusCodeNotOK(let statusCode, let errorMessage, let data):