// 指定的文件清单复制到本地目录
public static IEnumerator CopyStreamingAssets(string outputPath, FileListManifest fileListManifest,
Action oncomplete)
{
var count = fileListManifest.files.Count;
for (var i = 0; i < count; i++)
{
var file = fileListManifest.files[i];
var outputFile = Path.Combine(outputPath, file.name);
if (!File.Exists(outputFile))
{
var streamingAssetsFilePath = GetStreamingAssetsFilePath(file.name);
var uwr = UnityWebRequest.Get(streamingAssetsFilePath);
yield return(uwr.SendWebRequest());
if (uwr.error == null && uwr.responseCode == 200)
{
try
{
var bytes = uwr.downloadHandler.data;
var checksum = Crc16.ComputeChecksum(bytes);
var size = bytes.Length;
var metaFile = Path.Combine(outputPath, file.name + Metadata.Ext);
var metadata = new Metadata()
{
checksum = Crc16.ToString(checksum),
size = size,
};
var metaJson = JsonUtility.ToJson(metadata);
File.WriteAllText(metaFile, metaJson);
File.WriteAllBytes(outputFile, bytes);
}
catch (Exception exception)
{
Debug.LogWarningFormat("CopyStreamingAssets exception: {0}\n{1}",
streamingAssetsFilePath, exception);
}
}
else
{
Debug.LogWarningFormat("CopyStreamingAssets request failed {0}: {1} {2}",
streamingAssetsFilePath, uwr.responseCode,
uwr.error);
}
}
}
oncomplete?.Invoke();
}
private void _HttpDownload(string url, int partialSize, byte[] buffer, Utils.Crc16 crc, Stream targetStream, int timeout)
{
PrintDebug($"downloading from {url}");
var uri = new Uri(url);
var req = WebRequest.CreateHttp(uri);
req.Method = WebRequestMethods.Http.Get;
req.ContentType = BundleContentType;
req.ReadWriteTimeout = 10000;
if (timeout > 0)
{
req.Timeout = timeout * 1000;
}
if (partialSize > 0)
{
req.AddRange(partialSize);
}
using (var rsp = req.GetResponse())
{
using (var webStream = rsp.GetResponseStream())
{
var recvAll = 0L;
while (recvAll < rsp.ContentLength)
{
var recv = webStream.Read(buffer, 0, buffer.Length);
if (recv > 0 && _running)
{
recvAll += recv;
targetStream.Write(buffer, 0, recv);
crc.Update(buffer, 0, recv);
_progress = Mathf.Clamp01((float)(recvAll + partialSize) / _size);
if (_slow > 0)
{
Thread.Sleep(_slow); // 模拟低速下载
}
// PrintDebug($"{recvAll + partialSize}, {_size}, {_progress}");
}
else
{
break;
}
}
}
}
// PrintDebug($"download exited");
}
// 打开指定的清单文件 (带校验)
public static Manifest ParseManifestFile(string filePath, FileEntry fileEntry, string password)
{
if (File.Exists(filePath))
{
using (var fs = File.OpenRead(filePath))
{
var crc = new Crc16();
crc.Update(fs);
if (crc.hex == fileEntry.checksum && fs.Length == fileEntry.size)
{
fs.Seek(0, SeekOrigin.Begin);
return(ParseManifestStream(fs, fileEntry, password));
}
}
}
return(null);
}
private void DownloadExec(object state)
{
var buffer = new byte[BufferSize];
var tempPath = _finalPath + PartExt;
var metaPath = _finalPath + Metadata.Ext;
var retry = 0;
FileStream fileStream = null;
while (true)
{
string error = null;
var crc = new Utils.Crc16();
var partialSize = 0;
var success = true;
if (fileStream == null)
{
try
{
if (File.Exists(tempPath)) // 处理续传
{
var fileInfo = new FileInfo(tempPath);
fileStream = fileInfo.Open(FileMode.OpenOrCreate, FileAccess.ReadWrite);
partialSize = (int)fileInfo.Length;
if (partialSize > _size) // 目标文件超过期望大小, 直接废弃
{
fileStream.SetLength(0);
partialSize = 0;
}
else if (partialSize <= _size) // 续传
{
crc.Update(fileStream);
PrintDebug($"partial check {partialSize} && {_size} ({crc.hex})");
}
}
else // 创建下载文件
{
fileStream = File.Open(tempPath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
fileStream.SetLength(0);
}
}
catch (Exception exception)
{
// PrintError($"file exception: {exception}");
error = $"file exception: {exception}";
success = false;
}
}
else
{
fileStream.SetLength(0L);
}
if (success && (_size <= 0 || partialSize < _size))
{
try
{
_HttpDownload(this.url, partialSize, buffer, crc, fileStream, _timeout);
}
catch (Exception exception)
{
// PrintError($"network exception: {exception}");
error = $"network exception: {exception}";
success = false;
}
}
if (success && fileStream.Length != _size)
{
if (_size > 0)
{
// PrintError($"filesize exception: {fileStream.Length} != {_size}");
error = $"wrong file size: {fileStream.Length} != {_size}";
success = false;
}
else
{
_size = (int)fileStream.Length;
}
}
else if (success && crc.hex != _checksum)
{
if (_checksum != null)
{
// PrintError($"checksum exception: {crc.hex} != {_checksum}");
error = $"corrupted file: {crc.hex} != {_checksum}";
success = false;
}
else
{
_checksum = crc.hex;
}
}
lock (this)
{
if (_isDone || _destroy)
{
success = false;
}
}
if (success)
{
try
{
// _WriteStream(buffer, fileStream, finalPath);
fileStream.Close();
fileStream = null;
if (File.Exists(_finalPath))
{
File.Delete(_finalPath);
}
File.Move(tempPath, _finalPath);
_WriteMetadata(metaPath);
Complete(null);
// PrintDebug("download succeeded");
break;
}
catch (Exception exception)
{
// PrintError($"write exception: {exception}");
error = $"write exception: {exception}";
success = false;
}
}
if (!Retry(++retry))
{
if (fileStream != null)
{
fileStream.Close();
fileStream = null;
}
Complete(error ?? "unknown error");
PrintError($"[stop] download failed ({error})");
break;
}
Thread.Sleep(1000);
PrintError($"[retry] ({_destroy}) download failed ({error})");
}
PrintDebug("download task thread exited");
}