[Feat] NetworkService 플러그인 구현

* feat: 네트워크 플러그인 프로토콜 구현

* feat: 네트워크 플러그인 구현

* feat: networkService에 플러그인 적용

* refactor: 코드래빗 리뷰 반영

* refactor: 코드 리뷰 반영

Author: taipaise

Projects/DataSource/Sources/NetworkService/NetworkError.swift

@@ -5,12 +5,15 @@
 //  Created by 최정인 on 6/23/25.
 //
 
-enum NetworkError: Error, CustomStringConvertible {
+enum NetworkError: Error, CustomStringConvertible, Comparable {
     case invalidURL
     case invalidResponse
     case invalidStatusCode(statusCode: Int)
     case emptyData
     case decodingError
+    case needRetry
+    case noRetry
+    case unknown(description: String)
 
     var description: String {
         switch self {
@@ -24,6 +27,12 @@ enum NetworkError: Error, CustomStringConvertible {
             return "emptyData"
         case .decodingError:
             return "decodingError"
+        case .needRetry:
+            return "request need retry"
+        case .noRetry:
+            return "request don't need retry"
+        case .unknown(let description):
+            return "unknown error: \(description)"
         }
     }
 }

Projects/DataSource/Sources/NetworkService/NetworkService.swift

@@ -11,17 +11,70 @@ import Shared
 final class NetworkService {
     static let shared = NetworkService()
     private let decoder = JSONDecoder()
+    private let plugins: [NetworkPlugin]
+    private let maxRetryCount = 1
 
-    private init() { }
+    private init() {
+        plugins = [
+            TokenInjectionPlugin(),
+            RefreshTokenPlugin(),
+            RetryPlugin()]
+    }
+
+    func request<T: Decodable>(
+        endpoint: Endpoint,
+        type: T.Type,
+        withPlugins: Bool = true
+    ) async throws -> T? {
+        var retryCount = 0
 
-    func request<T: Decodable>(endpoint: Endpoint, type: T.Type) async throws -> T? {
+        while true {
+            do {
+                return try await performRequest(
+                    endpoint: endpoint,
+                    type: type,
+                    withPlugins: withPlugins)
+            } catch let error as NetworkError {
+                guard
+                    error == .needRetry,
+                    retryCount < maxRetryCount
+                else { throw error }
+
+                retryCount += 1
+                continue
+            }
+        }
+    }
+
+    private func performRequest<T: Decodable>(
+        endpoint: Endpoint,
+        type: T.Type,
+        withPlugins: Bool = true
+    ) async throws -> T? {
         var request = try endpoint.makeURLRequest()
-        if endpoint.isAuthorized {
-            let accessToken = try TokenManager.shared.loadToken(tokenType: .accessToken)
-            request.headers["Authorization"] = "Bearer \(accessToken)"
+
+        if withPlugins {
+            for plugin in plugins {
+                request = try await plugin.willSend(request: request, endpoint: endpoint)
+            }
         }
+
         let (data, response) = try await URLSession.shared.data(for: request)
 
+        // TODO: - 로깅 로직 수정
+        if let httpResponse = response as? HTTPURLResponse {
+            BitnagilLogger.log(logType: .info, message: "응답 코드: \(httpResponse.statusCode)")
+        }
+
+        if withPlugins {
+            for plugin in plugins {
+                try await plugin.didReceive(
+                    response: response,
+                    data: data,
+                    endpoint: endpoint)
+            }
+        }
+
         guard let httpResponse = response as? HTTPURLResponse
         else { throw NetworkError.invalidResponse }
 
@@ -39,7 +92,7 @@ final class NetworkService {
 
             guard let responseDTO = baseResponse.data
             else { return nil }
-            
+
             return responseDTO
         } catch {
             throw NetworkError.decodingError

Projects/DataSource/Sources/NetworkService/Plugin/RefreshTokenPlugin.swift

@@ -0,0 +1,49 @@
+//
+//  RefreshTokenPlugin.swift
+//  DataSource
+//
+//  Created by 이동현 on 7/29/25.
+//
+
+import Foundation
+import Shared
+
+struct RefreshTokenPlugin: NetworkPlugin {
+    func willSend(request: URLRequest, endpoint: Endpoint) async throws -> URLRequest {
+        return request
+    }
+
+    func didReceive(response: URLResponse, data: Data?, endpoint: Endpoint) async throws {
+        guard
+            let httpResponse = response as? HTTPURLResponse,
+            httpResponse.statusCode == 401
+        else { return }
+
+
+        try await refreshAccessToken()
+    }
+
+    private func refreshAccessToken() async throws {
+        do {
+            let tokenManager = TokenManager.shared
+
+            let refreshToken = try tokenManager.loadToken(tokenType: .refreshToken)
+            let endpoint = AuthEndpoint.reissue(refreshToken: refreshToken)
+
+            guard let tokenResponse = try await NetworkService.shared.request(
+                endpoint: endpoint,
+                type: TokenResponseDTO.self,
+                withPlugins: false)
+            else { throw NetworkError.unknown(description: "토큰 갱신 실패") }
+
+            try tokenManager.saveToken(token: tokenResponse.accessToken, tokenType: .accessToken)
+            try tokenManager.saveToken(token: tokenResponse.refreshToken, tokenType: .refreshToken)
+
+            BitnagilLogger.log(logType: .debug, message: "AccessToken Saved: \(tokenResponse.accessToken)")
+            BitnagilLogger.log(logType: .debug, message: "RefreshToken Saved: \(tokenResponse.refreshToken)")
+        } catch {
+            BitnagilLogger.log(logType: .error, message: "\(error.localizedDescription)")
+            throw error
+        }
+    }
+}

Projects/DataSource/Sources/NetworkService/Plugin/RetryPlugin.swift

@@ -0,0 +1,31 @@
+//
+//  RetryPlugin.swift
+//  DataSource
+//
+//  Created by 이동현 on 7/29/25.
+//
+
+import Foundation
+
+struct RetryPlugin: NetworkPlugin {
+    func willSend(request: URLRequest, endpoint: Endpoint) async throws -> URLRequest {
+        return request
+    }
+
+    func didReceive(
+        response: URLResponse,
+        data: Data?,
+        endpoint: Endpoint
+    ) async throws {
+        guard let httpResponse = response as? HTTPURLResponse else { return }
+
+        switch httpResponse.statusCode {
+        case 200..<300:
+            return
+        case 401: // TODO: - 재전송 정책 필요시 조정하기!!
+            throw NetworkError.needRetry
+        default:
+            throw NetworkError.noRetry
+        }
+    }
+}

Projects/DataSource/Sources/NetworkService/Plugin/TokenInjectionPlugin.swift

@@ -0,0 +1,21 @@
+//
+//  TokenInjectionPlugin.swift
+//  DataSource
+//
+//  Created by 이동현 on 7/29/25.
+//
+
+import Foundation
+
+struct TokenInjectionPlugin: NetworkPlugin {
+    func willSend(request: URLRequest, endpoint: any Endpoint) async throws -> URLRequest {
+        guard endpoint.isAuthorized else { return request }
+
+        var newRequest = request
+        let accessToken = try TokenManager.shared.loadToken(tokenType: .accessToken)
+        newRequest.setValue("Bearer \(accessToken)", forHTTPHeaderField: "Authorization")
+        return newRequest
+    }
+    
+    func didReceive(response: URLResponse, data: Data?, endpoint: any Endpoint) async throws {}
+}

Projects/DataSource/Sources/NetworkService/Protocol/NetworkPlugin.swift

@@ -0,0 +1,27 @@
+//
+//  NetworkPlugin.swift
+//  DataSource
+//
+//  Created by 이동현 on 7/29/25.
+//
+
+import Foundation
+
+protocol NetworkPlugin {
+    /// 네트워크 요청 전처리를 진행합니다.
+    /// - Parameters:
+    ///   - request: 요청할 request 객체
+    ///   - endpoint: 요청할 엔드포인트
+    /// - Returns: URLRequest 객체
+    func willSend(request: URLRequest, endpoint: Endpoint) async throws -> URLRequest
+
+    /// 네트워크 응답 후처리를 진행합니다.
+    /// - Parameters:
+    ///   - response: URLResponse 객체
+    ///   - data: 통신 후 받은 데이터
+    ///   - endpoint: 요청한 endpoint
+    func didReceive(
+        response: URLResponse,
+        data: Data?,
+        endpoint: Endpoint) async throws
+}