refactor the runtime code

重构了运行时代码，支持全新的文件系统。
2024-07-04 20:36:26 +08:00
parent 2987d356b6
commit ff02da5c54
313 changed files with 9889 additions and 7234 deletions
@@ -0,0 +1,277 @@
+using System;
+using System.IO;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace YooAsset
+{
+    internal class DefaultWebFileSystem : IFileSystem
+    {
+        public class FileWrapper
+        {
+            public string FileName { private set; get; }
+
+            public FileWrapper(string fileName)
+            {
+                FileName = fileName;
+            }
+        }
+
+        protected readonly Dictionary<string, FileWrapper> _wrappers = new Dictionary<string, FileWrapper>(10000);
+        protected readonly Dictionary<string, string> _webFilePaths = new Dictionary<string, string>(10000);
+        protected string _webPackageRoot = string.Empty;
+
+
+        /// <summary>
+        /// 包裹名称
+        /// </summary>
+        public string PackageName { private set; get; }
+
+        /// <summary>
+        /// 文件访问权限
+        /// </summary>
+        public EFileAccess FileSystemAccess
+        {
+            get
+            {
+                return EFileAccess.ReadWrite;
+            }
+        }
+
+        /// <summary>
+        /// 文件根目录
+        /// </summary>
+        public string FileRoot
+        {
+            get
+            {
+                return _webPackageRoot;
+            }
+        }
+
+        /// <summary>
+        /// 文件数量
+        /// </summary>
+        public int FileCount
+        {
+            get
+            {
+                return 0;
+            }
+        }
+
+        #region 自定义参数
+        public bool AllowCrossAccess { private set; get; } = false;
+
+        /// <summary>
+        /// 自定义参数：远程服务接口
+        /// </summary>
+        public IRemoteServices RemoteServices { private set; get; } = null;
+        #endregion
+
+
+        public DefaultWebFileSystem()
+        {
+        }
+        public virtual FSInitializeFileSystemOperation InitializeFileSystemAsync()
+        {
+            var operation = new DWFSInitializeOperation(this);
+            OperationSystem.StartOperation(PackageName, operation);
+            return operation;
+        }
+        public virtual FSLoadPackageManifestOperation LoadPackageManifestAsync(params object[] args)
+        {
+            string packageVersion = args[0] as string;
+            int timeout = (int)args[1];
+
+            if (AllowCrossAccess)
+            {
+                var operation = new DWFSLoadRemotePackageManifestOperation(this, packageVersion, timeout);
+                OperationSystem.StartOperation(PackageName, operation);
+                return operation;
+            }
+            else
+            {
+                var operation = new DWFSLoadWebPackageManifestOperation(this, timeout);
+                OperationSystem.StartOperation(PackageName, operation);
+                return operation;
+            }
+        }
+        public virtual FSRequestPackageVersionOperation RequestPackageVersionAsync(params object[] args)
+        {
+            bool appendTimeTicks = (bool)args[0];
+            int timeout = (int)args[1];
+            var operation = new DWFSRequestPackageVersionOperation(this, appendTimeTicks, timeout);
+            OperationSystem.StartOperation(PackageName, operation);
+            return operation;
+        }
+        public virtual FSClearAllBundleFilesOperation ClearAllBundleFilesAsync(params object[] args)
+        {
+            var operation = new DWFSClearAllBundleFilesOperation(this);
+            OperationSystem.StartOperation(PackageName, operation);
+            return operation;
+        }
+        public virtual FSClearUnusedBundleFilesOperation ClearUnusedBundleFilesAsync(params object[] args)
+        {
+            var operation = new DWFSClearUnusedBundleFilesOperation(this);
+            OperationSystem.StartOperation(PackageName, operation);
+            return operation;
+        }
+        public virtual FSDownloadFileOperation DownloadFileAsync(params object[] args)
+        {
+            throw new System.NotImplementedException();
+        }
+
+        public virtual void SetParameter(string name, object value)
+        {
+            if (name == "ALLOW_CROSS_ACCESS")
+            {
+                AllowCrossAccess = (bool)value;
+            }
+            else if (name == "REMOTE_SERVICES")
+            {
+                RemoteServices = (IRemoteServices)value;
+            }
+            else
+            {
+                YooLogger.Warning($"Invalid parameter : {name}");
+            }
+        }
+        public virtual void OnCreate(string packageName, string rootDirectory)
+        {
+            PackageName = packageName;
+
+            if (string.IsNullOrEmpty(rootDirectory))
+                rootDirectory = GetDefaultWebRoot();
+
+            _webPackageRoot = PathUtility.Combine(rootDirectory, packageName);
+        }
+        public virtual void OnUpdate()
+        {
+        }
+
+        public virtual bool Belong(PackageBundle bundle)
+        {
+            return true;
+        }
+        public virtual bool Belong(string bundleGUID)
+        {
+            return true;
+        }
+        public virtual bool Exists(PackageBundle bundle)
+        {
+            return false;
+        }
+        public virtual bool Exists(string bundleGUID)
+        {
+            return false;
+        }
+
+        public virtual bool CheckNeedDownload(PackageBundle bundle)
+        {
+            return false;
+        }
+        public virtual bool CheckNeedUnpack(PackageBundle bundle)
+        {
+            return false;
+        }
+        public virtual bool CheckNeedImport(PackageBundle bundle)
+        {
+            return false;
+        }
+
+        public virtual bool WriteFile(PackageBundle bundle, string copyPath)
+        {
+            throw new System.NotImplementedException();
+        }
+        public virtual bool DeleteFile(PackageBundle bundle)
+        {
+            throw new System.NotImplementedException();
+        }
+        public virtual bool DeleteFile(string bundleGUID)
+        {
+            throw new System.NotImplementedException();
+        }
+        public virtual EFileVerifyResult VerifyFile(PackageBundle bundle)
+        {
+            return EFileVerifyResult.Succeed;
+        }
+
+        public virtual byte[] ReadFileBytes(PackageBundle bundle)
+        {
+            throw new System.NotImplementedException();
+        }
+        public virtual string ReadFileText(PackageBundle bundle)
+        {
+            throw new System.NotImplementedException();
+        }
+
+        public virtual FSLoadBundleOperation LoadBundleFile(PackageBundle bundle)
+        {
+            var operation = new DWFSLoadAssetBundleOperation(this, bundle);
+            OperationSystem.StartOperation(PackageName, operation);
+            return operation;
+        }
+        public virtual void UnloadBundleFile(PackageBundle bundle, object result)
+        {
+            AssetBundle assetBundle = result as AssetBundle;
+            if (assetBundle == null)
+                return;
+
+            if (assetBundle != null)
+                assetBundle.Unload(true);
+        }
+
+        #region 内部方法
+        protected string GetDefaultWebRoot()
+        {
+            string path = PathUtility.Combine(UnityEngine.Application.streamingAssetsPath, YooAssetSettingsData.Setting.DefaultYooFolderName);
+            return path;
+        }
+        public string GetWebFileLoadPath(PackageBundle bundle)
+        {
+            if (_webFilePaths.TryGetValue(bundle.BundleGUID, out string filePath) == false)
+            {
+                filePath = PathUtility.Combine(_webPackageRoot, bundle.FileName);
+                _webFilePaths.Add(bundle.BundleGUID, filePath);
+            }
+            return filePath;
+        }
+        public string GetCatalogFileLoadPath()
+        {
+            string fileName = Path.GetFileNameWithoutExtension(DefaultBuildinFileSystemDefine.BuildinCatalogFileName);
+            return PathUtility.Combine(YooAssetSettingsData.Setting.DefaultYooFolderName, PackageName, fileName);
+        }
+        public string GetWebPackageVersionFilePath()
+        {
+            string fileName = YooAssetSettingsData.GetPackageVersionFileName(PackageName);
+            return PathUtility.Combine(FileRoot, fileName);
+        }
+        public string GetWebPackageHashFilePath(string packageVersion)
+        {
+            string fileName = YooAssetSettingsData.GetPackageHashFileName(PackageName, packageVersion);
+            return PathUtility.Combine(FileRoot, fileName);
+        }
+        public string GetWebPackageManifestFilePath(string packageVersion)
+        {
+            string fileName = YooAssetSettingsData.GetManifestBinaryFileName(PackageName, packageVersion);
+            return PathUtility.Combine(FileRoot, fileName);
+        }
+
+        /// <summary>
+        /// 记录缓存信息
+        /// </summary>
+        public bool Record(string bundleGUID, FileWrapper wrapper)
+        {
+            if (_wrappers.ContainsKey(bundleGUID))
+            {
+                YooLogger.Error($"{nameof(DefaultWebFileSystem)} has element : {bundleGUID}");
+                return false;
+            }
+
+            _wrappers.Add(bundleGUID, wrapper);
+            return true;
+        }
+        #endregion
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 0772e17daa1b32b4a80a6211396a50e8
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: fe53f557bb5cf3242a04b3fce756dd38
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,20 @@
+
+namespace YooAsset
+{
+    internal sealed class DWFSClearAllBundleFilesOperation : FSClearAllBundleFilesOperation
+    {
+        private readonly DefaultWebFileSystem _fileSystem;
+
+        internal DWFSClearAllBundleFilesOperation(DefaultWebFileSystem fileSystem)
+        {
+            _fileSystem = fileSystem;
+        }
+        internal override void InternalOnStart()
+        {
+            Status = EOperationStatus.Succeed;
+        }
+        internal override void InternalOnUpdate()
+        {
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 68578d4c5e39a554aa3df2e7ec5218e9
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,20 @@
+
+namespace YooAsset
+{
+    internal sealed class DWFSClearUnusedBundleFilesOperation : FSClearUnusedBundleFilesOperation
+    {
+        private readonly DefaultWebFileSystem _fileSystem;
+
+        internal DWFSClearUnusedBundleFilesOperation(DefaultWebFileSystem fileSystem)
+        {
+            _fileSystem = fileSystem;
+        }
+        internal override void InternalOnStart()
+        {
+            Status = EOperationStatus.Succeed;
+        }
+        internal override void InternalOnUpdate()
+        {
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 1560968379b66d440a94382b2a311a15
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,137 @@
+using System.IO;
+using UnityEngine;
+using UnityEngine.Networking;
+
+namespace YooAsset
+{
+    internal class DWFSDownloadWebFileOperation : DefaultDownloadFileOperation
+    {
+        private readonly DefaultWebFileSystem _fileSystem;
+        private DownloadHandlerAssetBundle _downloadhandler;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 下载结果
+        /// </summary>
+        public AssetBundle Result { private set; get; }
+
+
+        internal DWFSDownloadWebFileOperation(DefaultWebFileSystem fileSystem, PackageBundle bundle, string mainURL, string fallbackURL, int failedTryAgain, int timeout)
+            : base(bundle, mainURL, fallbackURL, failedTryAgain, timeout)
+        {
+            _fileSystem = fileSystem;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.CreateRequest;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            // 创建下载器
+            if (_steps == ESteps.CreateRequest)
+            {
+                // 获取请求地址
+                _requestURL = GetRequestURL();
+
+                // 重置变量
+                _isAbort = false;
+                _latestDownloadBytes = 0;
+                _latestDownloadRealtime = Time.realtimeSinceStartup;
+                DownloadProgress = 0f;
+                DownloadedBytes = 0;
+
+                // 重置计时器
+                if (_tryAgainTimer > 0f)
+                    YooLogger.Warning($"Try again download : {_requestURL}");
+                _tryAgainTimer = 0f;
+
+                // 创建下载器
+                CreateWebRequest();
+
+                _steps = ESteps.CheckRequest;
+            }
+
+            // 检测下载结果
+            if (_steps == ESteps.CheckRequest)
+            {
+                DownloadProgress = _webRequest.downloadProgress;
+                DownloadedBytes = (long)_webRequest.downloadedBytes;
+                Progress = DownloadProgress;
+                if (_webRequest.isDone == false)
+                {
+                    CheckRequestTimeout();
+                    return;
+                }
+
+                // 检查网络错误
+                if (CheckRequestResult())
+                {
+                    _steps = ESteps.Done;
+                    Result = _downloadhandler.assetBundle;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.TryAgain;
+                }
+
+                // 注意：最终释放请求器
+                DisposeWebRequest();
+            }
+
+            // 重新尝试下载
+            if (_steps == ESteps.TryAgain)
+            {
+                if (FailedTryAgain <= 0)
+                {
+                    Status = EOperationStatus.Failed;
+                    _steps = ESteps.Done;
+                    YooLogger.Error(Error);
+                    return;
+                }
+
+                _tryAgainTimer += Time.unscaledDeltaTime;
+                if (_tryAgainTimer > 1f)
+                {
+                    FailedTryAgain--;
+                    _steps = ESteps.CreateRequest;
+                    YooLogger.Warning(Error);
+                }
+            }
+        }
+        internal override void InternalOnAbort()
+        {
+            _steps = ESteps.Done;
+            DisposeWebRequest();
+        }
+
+        private void CreateWebRequest()
+        {
+            uint unityCRC = Bundle.UnityCRC;
+            Hash128 fileHash = Hash128.Parse(Bundle.FileHash);
+
+            // 注意：优先从浏览器缓存里获取文件
+            // The file hash defining the version of the asset bundle.
+            _webRequest = DownloadSystemHelper.NewUnityWebRequestGet(_requestURL);
+            _downloadhandler = new DownloadHandlerAssetBundle(_requestURL, fileHash, unityCRC);
+#if UNITY_2020_3_OR_NEWER
+            _downloadhandler.autoLoadAssetBundle = false;
+#endif
+            _webRequest.downloadHandler = _downloadhandler;
+            _webRequest.disposeDownloadHandlerOnDispose = true;
+            _webRequest.SendWebRequest();
+        }
+        private void DisposeWebRequest()
+        {
+            if (_webRequest != null)
+            {
+                //注意：引擎底层会自动调用Abort方法
+                _webRequest.Dispose();
+                _webRequest = null;
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 3b82b4b846083d34b958320b584d8d9b
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,49 @@
+
+namespace YooAsset
+{
+    internal partial class DWFSInitializeOperation : FSInitializeFileSystemOperation
+    {
+        private enum ESteps
+        {
+            None,
+            LoadCatalogFile,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private LoadWebCatalogFileOperation _loadCatalogFileOp;
+        private ESteps _steps = ESteps.None;
+
+
+        public DWFSInitializeOperation(DefaultWebFileSystem fileSystem)
+        {
+            _fileSystem = fileSystem;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.LoadCatalogFile;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.LoadCatalogFile)
+            {
+                if (_loadCatalogFileOp == null)
+                {
+                    _loadCatalogFileOp = new LoadWebCatalogFileOperation(_fileSystem);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _loadCatalogFileOp);
+                }
+
+                if (_loadCatalogFileOp.IsDone == false)
+                    return;
+
+                // 说明：应用程序内不一定存在序列化文件
+                // 注意：总是返回成功
+                _steps = ESteps.Done;
+                Status = EOperationStatus.Succeed;
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 4c7cf2dca805b0b4d91cb5e0782dcb0c
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,87 @@
+
+namespace YooAsset
+{
+    internal class DWFSLoadAssetBundleOperation : FSLoadBundleOperation
+    {
+        private enum ESteps
+        {
+            None,
+            DownloadFile,
+            CheckResult,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly PackageBundle _bundle;
+        private DWFSDownloadWebFileOperation _downloadWebFileOp;
+        private ESteps _steps = ESteps.None;
+
+
+        internal DWFSLoadAssetBundleOperation(DefaultWebFileSystem fileSystem, PackageBundle bundle)
+        {
+            _fileSystem = fileSystem;
+            _bundle = bundle;
+        }
+        internal override void InternalOnStart()
+        {
+            DownloadProgress = 0f;
+            DownloadedBytes = 0;
+            _steps = ESteps.DownloadFile;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.DownloadFile)
+            {
+                if (_downloadWebFileOp == null)
+                {
+                    int failedTryAgain = int.MaxValue;
+                    int timeout = 60;
+                    string mainURL = _fileSystem.RemoteServices.GetRemoteMainURL(_bundle.FileName);
+                    string fallbackURL = _fileSystem.RemoteServices.GetRemoteFallbackURL(_bundle.FileName);
+                    _downloadWebFileOp = new DWFSDownloadWebFileOperation(_fileSystem, _bundle, mainURL, fallbackURL, failedTryAgain, timeout);
+                }
+
+                DownloadProgress = _downloadWebFileOp.DownloadProgress;
+                DownloadedBytes = _downloadWebFileOp.DownloadedBytes;
+                Progress = _downloadWebFileOp.Progress;
+                if (_downloadWebFileOp.IsDone == false)
+                    return;
+
+                if (_downloadWebFileOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Result = _downloadWebFileOp.Result;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _downloadWebFileOp.Error;
+                }
+            }
+        }
+
+        public override void WaitForAsyncComplete()
+        {
+            if (IsDone == false)
+            {
+                _steps = ESteps.Done;
+                Status = EOperationStatus.Failed;
+                Error = "WebGL platform not support sync load method !";
+                UnityEngine.Debug.LogError(Error);
+            }
+        }
+        public override void AbortDownloadOperation()
+        {
+            if (_steps == ESteps.DownloadFile)
+            {
+                if (_downloadWebFileOp != null)
+                    _downloadWebFileOp.SetAbort();
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: a50dacdf7a3ad7c40a4195126425bbec
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,198 @@
+
+namespace YooAsset
+{
+    internal class DWFSLoadWebPackageManifestOperation : FSLoadPackageManifestOperation
+    {
+        private enum ESteps
+        {
+            None,
+            RequestWebPackageVersion,
+            RequestWebPackageHash,
+            LoadWebPackageManifest,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly int _timeout;
+        private RequestWebPackageVersionOperation _requestWebPackageVersionOp;
+        private RequestWebPackageHashOperation _requestWebPackageHashOp;
+        private LoadWebPackageManifestOperation _loadWebPackageManifestOp;
+        private ESteps _steps = ESteps.None;
+
+
+        public DWFSLoadWebPackageManifestOperation(DefaultWebFileSystem fileSystem, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.RequestWebPackageVersion;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestWebPackageVersion)
+            {
+                if (_requestWebPackageVersionOp == null)
+                {
+                    _requestWebPackageVersionOp = new RequestWebPackageVersionOperation(_fileSystem, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _requestWebPackageVersionOp);
+                }
+
+                if (_requestWebPackageVersionOp.IsDone == false)
+                    return;
+
+                if (_requestWebPackageVersionOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.RequestWebPackageHash;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _requestWebPackageVersionOp.Error;
+                }
+            }
+
+            if (_steps == ESteps.RequestWebPackageHash)
+            {
+                if (_requestWebPackageHashOp == null)
+                {
+                    string packageVersion = _requestWebPackageVersionOp.PackageVersion;
+                    _requestWebPackageHashOp = new RequestWebPackageHashOperation(_fileSystem, packageVersion, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _requestWebPackageHashOp);
+                }
+
+                if (_requestWebPackageHashOp.IsDone == false)
+                    return;
+
+                if (_requestWebPackageHashOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.LoadWebPackageManifest;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _requestWebPackageHashOp.Error;
+                }
+            }
+
+            if (_steps == ESteps.LoadWebPackageManifest)
+            {
+                if (_loadWebPackageManifestOp == null)
+                {
+                    string packageVersion = _requestWebPackageVersionOp.PackageVersion;
+                    string packageHash = _requestWebPackageHashOp.PackageHash;
+                    _loadWebPackageManifestOp = new LoadWebPackageManifestOperation(_fileSystem, packageVersion, packageHash);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _loadWebPackageManifestOp);
+                }
+
+                Progress = _loadWebPackageManifestOp.Progress;
+                if (_loadWebPackageManifestOp.IsDone == false)
+                    return;
+
+                if (_loadWebPackageManifestOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Result = _loadWebPackageManifestOp.Manifest;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _loadWebPackageManifestOp.Error;
+                }
+            }
+        }
+    }
+
+    internal class DWFSLoadRemotePackageManifestOperation : FSLoadPackageManifestOperation
+    {
+        private enum ESteps
+        {
+            None,
+            RequestRemotePackageHash,
+            LoadRemotePackageManifest,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly string _packageVersion;
+        private readonly int _timeout;
+        private RequestRemotePackageHashOperation _requestRemotePackageHashOp;
+        private LoadRemotePackageManifestOperation _loadRemotePackageManifestOp;
+        private ESteps _steps = ESteps.None;
+
+
+        public DWFSLoadRemotePackageManifestOperation(DefaultWebFileSystem fileSystem, string packageVersion, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _packageVersion = packageVersion;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.RequestRemotePackageHash;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestRemotePackageHash)
+            {
+                if (_requestRemotePackageHashOp == null)
+                {
+                    _requestRemotePackageHashOp = new RequestRemotePackageHashOperation(_fileSystem, _packageVersion, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _requestRemotePackageHashOp);
+                }
+
+                if (_requestRemotePackageHashOp.IsDone == false)
+                    return;
+
+                if (_requestRemotePackageHashOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.LoadRemotePackageManifest;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _requestRemotePackageHashOp.Error;
+                }
+            }
+
+            if (_steps == ESteps.LoadRemotePackageManifest)
+            {
+                if (_loadRemotePackageManifestOp == null)
+                {
+                    string packageHash = _requestRemotePackageHashOp.PackageHash;
+                    _loadRemotePackageManifestOp = new LoadRemotePackageManifestOperation(_fileSystem, _packageVersion, packageHash, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _loadRemotePackageManifestOp);
+                }
+
+                Progress = _loadRemotePackageManifestOp.Progress;
+                if (_loadRemotePackageManifestOp.IsDone == false)
+                    return;
+
+                if (_loadRemotePackageManifestOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Result = _loadRemotePackageManifestOp.Manifest;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _loadRemotePackageManifestOp.Error;
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 0d0f8063cfabb5d40b364f162ce49fc0
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,66 @@
+
+namespace YooAsset
+{
+    internal class DWFSRequestPackageVersionOperation : FSRequestPackageVersionOperation
+    {
+        private enum ESteps
+        {
+            None,
+            GetPackageVersion,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly bool _appendTimeTicks;
+        private readonly int _timeout;
+        private DefaultGetRemotePackageVersionOperation _getRemotePackageVersionOp;
+        private ESteps _steps = ESteps.None;
+
+
+        internal DWFSRequestPackageVersionOperation(DefaultWebFileSystem fileSystem, bool appendTimeTicks, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _appendTimeTicks = appendTimeTicks;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.GetPackageVersion;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.GetPackageVersion)
+            {
+                if (_getRemotePackageVersionOp == null)
+                {
+                    string packageName = _fileSystem.PackageName;
+                    string fileName = YooAssetSettingsData.GetPackageVersionFileName(packageName);
+                    string mainURL = _fileSystem.RemoteServices.GetRemoteMainURL(fileName);
+                    string fallbackURL = _fileSystem.RemoteServices.GetRemoteFallbackURL(fileName);
+                    _getRemotePackageVersionOp = new DefaultGetRemotePackageVersionOperation(packageName, mainURL, fallbackURL, _appendTimeTicks, _timeout);
+                    OperationSystem.StartOperation(packageName, _getRemotePackageVersionOp);
+                }
+
+                Progress = _getRemotePackageVersionOp.Progress;
+                if (_getRemotePackageVersionOp.IsDone == false)
+                    return;
+
+                if (_getRemotePackageVersionOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    PackageVersion = _getRemotePackageVersionOp.PackageVersion;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _getRemotePackageVersionOp.Error;
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 212a79e362fe6234c81fa79c3924dd20
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 0e91f62e8fc7c1f4592681b7881ad925
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,125 @@
+
+namespace YooAsset
+{
+    internal class LoadRemotePackageManifestOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            RequestFileData,
+            VerifyFileData,
+            LoadManifest,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly string _packageVersion;
+        private readonly string _packageHash;
+        private readonly int _timeout;
+        private UnityWebDataRequestOperation _webDataRequestOp;
+        private DeserializeManifestOperation _deserializer;
+        private int _requestCount = 0;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 加载的清单实例
+        /// </summary>
+        public PackageManifest Manifest { private set; get; }
+
+
+        internal LoadRemotePackageManifestOperation(DefaultWebFileSystem fileSystem, string packageVersion, string packageHash, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _packageVersion = packageVersion;
+            _packageHash = packageHash;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _requestCount = WebRequestCounter.GetRequestFailedCount(_fileSystem.PackageName, nameof(LoadRemotePackageManifestOperation));
+            _steps = ESteps.RequestFileData;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestFileData)
+            {
+                if (_webDataRequestOp == null)
+                {
+                    string fileName = YooAssetSettingsData.GetManifestBinaryFileName(_fileSystem.PackageName, _packageVersion);
+                    string url = GetDownloadRequestURL(fileName);
+                    _webDataRequestOp = new UnityWebDataRequestOperation(url, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _webDataRequestOp);
+                }
+
+                Progress = _webDataRequestOp.Progress;
+                if (_webDataRequestOp.IsDone == false)
+                    return;
+
+                if (_webDataRequestOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.VerifyFileData;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _webDataRequestOp.Error;
+                    WebRequestCounter.RecordRequestFailed(_fileSystem.PackageName, nameof(LoadRemotePackageManifestOperation));
+                }
+            }
+
+            if (_steps == ESteps.VerifyFileData)
+            {
+                string fileHash = HashUtility.BytesMD5(_webDataRequestOp.Result);
+                if (fileHash == _packageHash)
+                {
+                    _steps = ESteps.LoadManifest;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = "Failed to verify remote package manifest file!";
+                }
+            }
+
+            if (_steps == ESteps.LoadManifest)
+            {
+                if (_deserializer == null)
+                {
+                    _deserializer = new DeserializeManifestOperation(_webDataRequestOp.Result);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _deserializer);
+                }
+
+                Progress = _deserializer.Progress;
+                if (_deserializer.IsDone == false)
+                    return;
+
+                if (_deserializer.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Manifest = _deserializer.Manifest;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _deserializer.Error;
+                }
+            }
+        }
+
+        private string GetDownloadRequestURL(string fileName)
+        {
+            // 轮流返回请求地址
+            if (_requestCount % 2 == 0)
+                return _fileSystem.RemoteServices.GetRemoteMainURL(fileName);
+            else
+                return _fileSystem.RemoteServices.GetRemoteFallbackURL(fileName);
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 2c2153284d246964fb2146f9fdda311c
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,72 @@
+using System;
+using System.IO;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace YooAsset
+{
+    internal sealed class LoadWebCatalogFileOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            LoadCatalog,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 内置清单版本
+        /// </summary>
+        public string PackageVersion { private set; get; }
+
+        internal LoadWebCatalogFileOperation(DefaultWebFileSystem fileSystem)
+        {
+            _fileSystem = fileSystem;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.LoadCatalog;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.LoadCatalog)
+            {
+                string catalogFilePath = _fileSystem.GetCatalogFileLoadPath();
+                var catalog = Resources.Load<DefaultBuildinFileCatalog>(catalogFilePath);
+                if (catalog == null)
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = $"Failed to load catalog file : {catalogFilePath}";
+                    return;
+                }
+
+                if (catalog.PackageName != _fileSystem.PackageName)
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = $"The catalog file package name {catalog.PackageName} cannot match the file system package name {_fileSystem.PackageName}";
+                    return;
+                }
+
+                PackageVersion = catalog.PackageVersion;
+                foreach (var wrapper in catalog.Wrappers)
+                {
+                    var fileWrapper = new DefaultWebFileSystem.FileWrapper(wrapper.FileName);
+                    _fileSystem.Record(wrapper.BundleGUID, fileWrapper);
+                }
+
+                YooLogger.Log($"Package '{_fileSystem.PackageName}' catalog files count : {catalog.Wrappers.Count}");
+                _steps = ESteps.Done;
+                Status = EOperationStatus.Succeed;
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 4c34c01e10454c842819e066eef488cf
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,109 @@
+
+namespace YooAsset
+{
+    internal class LoadWebPackageManifestOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            RequestFileData,
+            VerifyFileData,
+            LoadManifest,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly string _packageVersion;
+        private readonly string _packageHash;
+        private UnityWebDataRequestOperation _webDataRequestOp;
+        private DeserializeManifestOperation _deserializer;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 加载的清单实例
+        /// </summary>
+        public PackageManifest Manifest { private set; get; }
+
+        internal LoadWebPackageManifestOperation(DefaultWebFileSystem fileSystem, string packageVersion, string packageHash)
+        {
+            _fileSystem = fileSystem;
+            _packageVersion = packageVersion;
+            _packageHash = packageHash;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.RequestFileData;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestFileData)
+            {
+                if (_webDataRequestOp == null)
+                {
+                    string filePath = _fileSystem.GetWebPackageManifestFilePath(_packageVersion);
+                    string url = DownloadSystemHelper.ConvertToWWWPath(filePath);
+                    _webDataRequestOp = new UnityWebDataRequestOperation(url);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _webDataRequestOp);
+                }
+
+                if (_webDataRequestOp.IsDone == false)
+                    return;
+
+                if (_webDataRequestOp.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.VerifyFileData;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _webDataRequestOp.Error;
+                }
+            }
+
+            if (_steps == ESteps.VerifyFileData)
+            {
+                string fileHash = HashUtility.BytesMD5(_webDataRequestOp.Result);
+                if (fileHash == _packageHash)
+                {
+                    _steps = ESteps.LoadManifest;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = "Failed to verify web package manifest file!";
+                }
+            }
+
+            if (_steps == ESteps.LoadManifest)
+            {
+                if (_deserializer == null)
+                {
+                    _deserializer = new DeserializeManifestOperation(_webDataRequestOp.Result);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _deserializer);
+                }
+
+                Progress = _deserializer.Progress;
+                if (_deserializer.IsDone == false)
+                    return;
+
+                if (_deserializer.Status == EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Manifest = _deserializer.Manifest;
+                    Status = EOperationStatus.Succeed;
+                }
+                else
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _deserializer.Error;
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 04a60c61990d93b4cb934ab1901a44f5
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,90 @@
+
+namespace YooAsset
+{
+    internal class RequestRemotePackageHashOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            RequestPackageHash,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly string _packageVersion;
+        private readonly int _timeout;
+        private UnityWebTextRequestOperation _webTextRequestOp;
+        private int _requestCount = 0;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 包裹哈希值
+        /// </summary>
+        public string PackageHash { private set; get; }
+
+
+        public RequestRemotePackageHashOperation(DefaultWebFileSystem fileSystem, string packageVersion, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _packageVersion = packageVersion;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _requestCount = WebRequestCounter.GetRequestFailedCount(_fileSystem.PackageName, nameof(RequestRemotePackageHashOperation));
+            _steps = ESteps.RequestPackageHash;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestPackageHash)
+            {
+                if (_webTextRequestOp == null)
+                {
+                    string fileName = YooAssetSettingsData.GetPackageHashFileName(_fileSystem.PackageName, _packageVersion);
+                    string url = GetDownloadRequestURL(fileName);
+                    _webTextRequestOp = new UnityWebTextRequestOperation(url, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _webTextRequestOp);
+                }
+
+                Progress = _webTextRequestOp.Progress;
+                if (_webTextRequestOp.IsDone == false)
+                    return;
+
+                if (_webTextRequestOp.Status != EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _webTextRequestOp.Error;
+                    WebRequestCounter.RecordRequestFailed(_fileSystem.PackageName, nameof(RequestRemotePackageHashOperation));
+                }
+                else
+                {
+                    PackageHash = _webTextRequestOp.Result;
+                    if (string.IsNullOrEmpty(PackageHash))
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Failed;
+                        Error = $"Remote package hash file content is empty !";
+                    }
+                    else
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Succeed;
+                    }
+                }
+            }
+        }
+
+        private string GetDownloadRequestURL(string fileName)
+        {
+            // 轮流返回请求地址
+            if (_requestCount % 2 == 0)
+                return _fileSystem.RemoteServices.GetRemoteMainURL(fileName);
+            else
+                return _fileSystem.RemoteServices.GetRemoteFallbackURL(fileName);
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 3f8269507a575884f935f9fbc71396ea
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,78 @@
+
+namespace YooAsset
+{
+    internal class RequestWebPackageHashOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            RequestPackageHash,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly string _packageVersion;
+        private readonly int _timeout;
+        private UnityWebTextRequestOperation _webTextRequestOp;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 包裹哈希值
+        /// </summary>
+        public string PackageHash { private set; get; }
+
+
+        public RequestWebPackageHashOperation(DefaultWebFileSystem fileSystem, string packageVersion, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _packageVersion = packageVersion;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.RequestPackageHash;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestPackageHash)
+            {
+                if (_webTextRequestOp == null)
+                {
+                    string filePath = _fileSystem.GetWebPackageHashFilePath(_packageVersion);
+                    string url = DownloadSystemHelper.ConvertToWWWPath(filePath);
+                    _webTextRequestOp = new UnityWebTextRequestOperation(url, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _webTextRequestOp);
+                }
+
+                Progress = _webTextRequestOp.Progress;
+                if (_webTextRequestOp.IsDone == false)
+                    return;
+
+                if (_webTextRequestOp.Status != EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _webTextRequestOp.Error;
+                }
+                else
+                {
+                    PackageHash = _webTextRequestOp.Result;
+                    if (string.IsNullOrEmpty(PackageHash))
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Failed;
+                        Error = $"Web package hash file content is empty !";
+                    }
+                    else
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Succeed;
+                    }
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: ead93dc6c4d5ed942b209ec2202087dc
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
@@ -0,0 +1,75 @@
+
+namespace YooAsset
+{
+    internal class RequestWebPackageVersionOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            RequestPackageVersion,
+            Done,
+        }
+
+        private readonly DefaultWebFileSystem _fileSystem;
+        private readonly int _timeout;
+        private UnityWebTextRequestOperation _webTextRequestOp;
+        private ESteps _steps = ESteps.None;
+
+        /// <summary>
+        /// 包裹版本
+        /// </summary>
+        public string PackageVersion { private set; get; }
+
+
+        internal RequestWebPackageVersionOperation(DefaultWebFileSystem fileSystem, int timeout)
+        {
+            _fileSystem = fileSystem;
+            _timeout = timeout;
+        }
+        internal override void InternalOnStart()
+        {
+            _steps = ESteps.RequestPackageVersion;
+        }
+        internal override void InternalOnUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.RequestPackageVersion)
+            {
+                if (_webTextRequestOp == null)
+                {
+                    string filePath = _fileSystem.GetWebPackageVersionFilePath();
+                    string url = DownloadSystemHelper.ConvertToWWWPath(filePath);
+                    _webTextRequestOp = new UnityWebTextRequestOperation(url, _timeout);
+                    OperationSystem.StartOperation(_fileSystem.PackageName, _webTextRequestOp);
+                }
+
+                if (_webTextRequestOp.IsDone == false)
+                    return;
+
+                if (_webTextRequestOp.Status != EOperationStatus.Succeed)
+                {
+                    _steps = ESteps.Done;
+                    Status = EOperationStatus.Failed;
+                    Error = _webTextRequestOp.Error;
+                }
+                else
+                {
+                    PackageVersion = _webTextRequestOp.Result;
+                    if (string.IsNullOrEmpty(PackageVersion))
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Failed;
+                        Error = $"Web package version file content is empty !";
+                    }
+                    else
+                    {
+                        _steps = ESteps.Done;
+                        Status = EOperationStatus.Succeed;
+                    }
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: bfa0e562b63f31141bbf04d4d5336d87
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: