[swift6] improve retry interceptor (#19988)

* [swift6] improve retry interceptor

* [swift6] improve retry interceptor

* [swift6] improve retry interceptor

Author: 4brunu

docs/faq-generators.md

@@ -350,21 +350,28 @@ First you implement the `OpenAPIInterceptor` protocol.
 public class BearerOpenAPIInterceptor: OpenAPIInterceptor {
     public init() {}
     
-    public func intercept(urlRequest: URLRequest, urlSession: URLSessionProtocol, openAPIClient: OpenAPIClient, completion: @escaping (Result<URLRequest, any Error>) -> Void) {
+    public func intercept<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, completion: @escaping (Result<URLRequest, any Error>) -> Void) {
+
+        guard requestBuilder.requiresAuthentication else {
+            // no authentication required
+            completion(.success(urlRequest))
+            return
+        }
+
         refreshTokenIfDoesntExist { token in
             
             // Change the current url request
             var newUrlRequest = urlRequest
             newUrlRequest.setValue("Bearer \(token)", forHTTPHeaderField: "Authorization")
             
             // Change the global headers
-            openAPIClient.customHeaders["Authorization"] = "Bearer \(token)"
+            requestBuilder.openAPIClient.customHeaders["Authorization"] = "Bearer \(token)"
             
             completion(.success(newUrlRequest))
         }
     }
     
-    public func retry(urlRequest: URLRequest, urlSession: URLSessionProtocol, openAPIClient: OpenAPIClient, data: Data?, response: URLResponse, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void) {
+    public func retry<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, data: Data?, response: URLResponse?, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void) {
         // We will analyse the response to see if it's a 401, and if it's a 401, we will refresh the token and retry the request
         refreshTokenIfUnauthorizedRequestResponse(
             data: data,
@@ -375,7 +382,7 @@ public class BearerOpenAPIInterceptor: OpenAPIInterceptor {
             if wasTokenRefreshed, let newToken = newToken {
                 
                 // Change the global headers
-                openAPIClient.customHeaders["Authorization"] = "Bearer \(newToken)"
+                requestBuilder.openAPIClient.customHeaders["Authorization"] = "Bearer \(newToken)"
                 
                 completion(.retry)
             } else {
@@ -397,7 +404,7 @@ public class BearerOpenAPIInterceptor: OpenAPIInterceptor {
         }
     }
     
-    func refreshTokenIfUnauthorizedRequestResponse(data: Data?, response: URLResponse, error: Error, completionHandler: @escaping (Bool, String?) -> Void) {
+    func refreshTokenIfUnauthorizedRequestResponse(data: Data?, response: URLResponse?, error: Error, completionHandler: @escaping (Bool, String?) -> Void) {
         if let response = response as? HTTPURLResponse, response.statusCode == 401 {
             startRefreshingToken { token in
                 completionHandler(true, token)

modules/openapi-generator/src/main/resources/swift6/libraries/urlsession/URLSessionImplementations.mustache

@@ -155,24 +155,48 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
                 switch result {
                 case .success(let modifiedRequest):
                     let dataTask = urlSession.dataTaskFromProtocol(with: modifiedRequest) { data, response, error in
-                    self.cleanupRequest()
-                        if let response, let error {
-                            self.openAPIClient.interceptor.retry(urlRequest: modifiedRequest, urlSession: urlSession, requestBuilder: self, data: data, response: response, error: error) { retry in
-                                switch retry {
-                                case .retry:
-                                    self.execute(completion: completion)
-
-                                case .dontRetry:
-                                    self.openAPIClient.apiResponseQueue.async {
-                                        self.processRequestResponse(urlRequest: request, data: data, response: response, error: error, completion: completion)
-                                    }
-                                }
-                            }
-                        } else {
-                            self.openAPIClient.apiResponseQueue.async {
-                                self.processRequestResponse(urlRequest: request, data: data, response: response, error: error, completion: completion)
-                            }
+                        self.cleanupRequest()
+
+                        if let error = error {
+                            self.retryRequest(
+                                urlRequest: modifiedRequest,
+                                urlSession: urlSession,
+                                statusCode: -1,
+                                data: data,
+                                response: response,
+                                error: error,
+                                completion: completion
+                            )
+                            return
                         }
+
+                        guard let httpResponse = response as? HTTPURLResponse else {
+                            self.retryRequest(
+                                urlRequest: modifiedRequest,
+                                urlSession: urlSession,
+                                statusCode: -2,
+                                data: data,
+                                response: response,
+                                error: DecodableRequestBuilderError.nilHTTPResponse,
+                                completion: completion
+                            )
+                            return
+                        }
+
+                        guard self.openAPIClient.successfulStatusCodeRange.contains(httpResponse.statusCode) else {
+                            self.retryRequest(
+                                urlRequest: modifiedRequest,
+                                urlSession: urlSession,
+                                statusCode: httpResponse.statusCode,
+                                data: data,
+                                response: httpResponse,
+                                error: DecodableRequestBuilderError.unsuccessfulHTTPStatusCode,
+                                completion: completion
+                            )
+                            return
+                        }
+
+                        self.processRequestResponse(urlRequest: request, data: data, httpResponse: httpResponse, error: error, completion: completion)
                     }
 
                     self.onProgressReady?(dataTask.progress)
@@ -204,22 +228,21 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
         }
     }
 
-    fileprivate func processRequestResponse(urlRequest: URLRequest, data: Data?, response: URLResponse?, error: Error?, completion: @escaping (_ result: Swift.Result<Response<T>, ErrorResponse>) -> Void) {
+    private func retryRequest(urlRequest: URLRequest, urlSession: URLSessionProtocol, statusCode: Int, data: Data?, response: URLResponse?, error: Error, completion: @Sendable @escaping (_ result: Swift.Result<Response<T>, ErrorResponse>) -> Void) {
+        self.openAPIClient.interceptor.retry(urlRequest: urlRequest, urlSession: urlSession, requestBuilder: self, data: data, response: response, error: error) { retry in
+            switch retry {
+            case .retry:
+                self.execute(completion: completion)
 
-        if let error = error {
-            completion(.failure(ErrorResponse.error(-1, data, response, error)))
-            return
-        }
-
-        guard let httpResponse = response as? HTTPURLResponse else {
-            completion(.failure(ErrorResponse.error(-2, data, response, DecodableRequestBuilderError.nilHTTPResponse)))
-            return
+            case .dontRetry:
+                self.openAPIClient.apiResponseQueue.async {
+                    completion(.failure(ErrorResponse.error(statusCode, data, response, error)))
+                }
+            }
         }
+    }
 
-        guard openAPIClient.successfulStatusCodeRange.contains(httpResponse.statusCode) else {
-            completion(.failure(ErrorResponse.error(httpResponse.statusCode, data, response, DecodableRequestBuilderError.unsuccessfulHTTPStatusCode)))
-            return
-        }
+    fileprivate func processRequestResponse(urlRequest: URLRequest, data: Data?, httpResponse: HTTPURLResponse, error: Error?, completion: @escaping (_ result: Swift.Result<Response<T>, ErrorResponse>) -> Void) {
 
         switch T.self {
         case is Void.Type:
@@ -297,22 +320,7 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
 }
 
 {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}open{{/nonPublicApi}} class URLSessionDecodableRequestBuilder<T: Decodable>: URLSessionRequestBuilder<T>, @unchecked Sendable {
-    override fileprivate func processRequestResponse(urlRequest: URLRequest, data: Data?, response: URLResponse?, error: Error?, completion: @escaping (_ result: Swift.Result<Response<T>, ErrorResponse>) -> Void) {
-
-        if let error = error {
-            completion(.failure(ErrorResponse.error(-1, data, response, error)))
-            return
-        }
-
-        guard let httpResponse = response as? HTTPURLResponse else {
-            completion(.failure(ErrorResponse.error(-2, data, response, DecodableRequestBuilderError.nilHTTPResponse)))
-            return
-        }
-
-        guard openAPIClient.successfulStatusCodeRange.contains(httpResponse.statusCode) else {
-            completion(.failure(ErrorResponse.error(httpResponse.statusCode, data, response, DecodableRequestBuilderError.unsuccessfulHTTPStatusCode)))
-            return
-        }
+    override fileprivate func processRequestResponse(urlRequest: URLRequest, data: Data?, httpResponse: HTTPURLResponse, error: Error?, completion: @escaping (_ result: Swift.Result<Response<T>, ErrorResponse>) -> Void) {
 
         switch T.self {
         case is String.Type:
@@ -353,9 +361,9 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
                 completion(.success(Response(response: httpResponse, body: filePath as! T, bodyData: data)))
 
             } catch let requestParserError as DownloadException {
-                completion(.failure(ErrorResponse.error(400, data, response, requestParserError)))
+                completion(.failure(ErrorResponse.error(400, data, httpResponse, requestParserError)))
             } catch {
-                completion(.failure(ErrorResponse.error(400, data, response, error)))
+                completion(.failure(ErrorResponse.error(400, data, httpResponse, error)))
             }
 
         case is Void.Type:
@@ -372,7 +380,7 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
                 if let expressibleByNilLiteralType = T.self as? ExpressibleByNilLiteral.Type {
                     completion(.success(Response(response: httpResponse, body: expressibleByNilLiteralType.init(nilLiteral: ()) as! T, bodyData: data)))
                 } else {
-                    completion(.failure(ErrorResponse.error(httpResponse.statusCode, nil, response, DecodableRequestBuilderError.emptyDataResponse)))
+                    completion(.failure(ErrorResponse.error(httpResponse.statusCode, nil, httpResponse, DecodableRequestBuilderError.emptyDataResponse)))
                 }
                 return
             }
@@ -383,7 +391,7 @@ fileprivate class URLSessionRequestBuilderConfiguration: @unchecked Sendable {
             case let .success(decodableObj):
                 completion(.success(Response(response: httpResponse, body: decodableObj, bodyData: unwrappedData)))
             case let .failure(error):
-                completion(.failure(ErrorResponse.error(httpResponse.statusCode, unwrappedData, response, error)))
+                completion(.failure(ErrorResponse.error(httpResponse.statusCode, unwrappedData, httpResponse, error)))
             }
         }
     }
@@ -694,7 +702,7 @@ extension JSONDataEncoding: ParameterEncoding {}
 {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} protocol OpenAPIInterceptor {
     func intercept<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, completion: @escaping (Result<URLRequest, Error>) -> Void)
 
-    func retry<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, data: Data?, response: URLResponse, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void)
+    func retry<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, data: Data?, response: URLResponse?, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void)
 }
 
 {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} class DefaultOpenAPIInterceptor: OpenAPIInterceptor {
@@ -704,7 +712,7 @@ extension JSONDataEncoding: ParameterEncoding {}
         completion(.success(urlRequest))
     }
 
-    public func retry<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, data: Data?, response: URLResponse, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void) {
+    public func retry<T>(urlRequest: URLRequest, urlSession: URLSessionProtocol, requestBuilder: RequestBuilder<T>, data: Data?, response: URLResponse?, error: Error, completion: @escaping (OpenAPIInterceptorRetry) -> Void) {
         completion(.dontRetry)
     }
 }