using System;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Threading.Tasks;
using System.Web;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.FileProviders.Physical;
using Microsoft.Extensions.Primitives;
using NewLife;
using NewLife.IO;
using NewLife.Log;
using NewLife.Web;
namespace Stardust.Extensions.Caches;
/// <summary>文件缓存提供者。本地文件不存在时，从上级拉取</summary>
class CacheFileProvider : IFileProvider
{
#region 属性
private static readonly Char[] _pathSeparators = new Char[2]
{
Path.DirectorySeparatorChar,
Path.AltDirectorySeparatorChar
};
private readonly ExclusionFilters _filters;
/// <summary>根目录</summary>
public String? Root { get; }
/// <summary>服务端地址。本地文件不存在时，将从这里下载</summary>
public String[]? Servers { get; set; }
/// <summary>目标服务器地址。下载文件带有sh脚本时，把其中的源服务器地址替换为目标服务器地址</summary>
public String? TargetServer { get; set; }
/// <summary>获取服务器地址的委托。方便实时更新</summary>
public Func<String[]>? GetServers { get; set; }
/// <summary>索引信息文件。列出扩展显示的文件内容</summary>
public String? IndexInfoFile { get; set; }
/// <summary>超时时间</summary>
public TimeSpan Timeout { get; set; } = TimeSpan.FromSeconds(5);
/// <summary>APM追踪</summary>
public ITracer? Tracer { get; set; }
#endregion
/// <summary>
/// 实例化
/// </summary>
/// <param name="root"></param>
/// <param name="server"></param>
/// <param name="filters"></param>
/// <exception cref="ArgumentException"></exception>
/// <exception cref="DirectoryNotFoundException"></exception>
public CacheFileProvider(String root, String? server, ExclusionFilters filters = ExclusionFilters.Sensitive)
{
if (!Path.IsPathRooted(root)) throw new ArgumentException("The path must be absolute.", nameof(root));
Root = Path.GetFullPath(root).EnsureEnd(Path.DirectorySeparatorChar + "");
if (!Directory.Exists(Root)) throw new DirectoryNotFoundException(Root);
Servers = server?.Split(",");
_filters = filters;
}
private String? GetFullPath(String path)
{
if (Root.IsNullOrEmpty()) return null;
if (PathNavigatesAboveRoot(path)) return null;
String fullPath;
try
{
fullPath = Path.GetFullPath(Path.Combine(Root, path));
}
catch
{
return null;
}
return !fullPath.StartsWithIgnoreCase(Root) ? null : fullPath;
}
/// <summary>
/// 获取文件信息
/// </summary>
/// <param name="subpath"></param>
/// <returns></returns>
public IFileInfo GetFileInfo(String subpath)
{
if (String.IsNullOrEmpty(subpath) || HasInvalidPathChars(subpath)) return new NotFoundFileInfo(subpath);
subpath = subpath.TrimStart(_pathSeparators);
if (Path.IsPathRooted(subpath)) return new NotFoundFileInfo(subpath);
var fullPath = GetFullPath(subpath);
if (fullPath == null) return new NotFoundFileInfo(subpath);
using var span = Tracer?.NewSpan(nameof(GetFileInfo), subpath);
// 本地不存在时，从服务器下载
var fi = fullPath.AsFile();
if (Path.GetFileName(fullPath).Contains('.'))
{
if (!fi.Exists)
fi = DownloadFile(subpath, fullPath).Result?.AsFile();
else if (fi.LastWriteTime.AddMonths(1) < DateTime.Now)
_ = Task.Run(() => DownloadFile(subpath, fullPath));
}
if (fi == null || !fi.Exists) return new NotFoundFileInfo(subpath);
var fileInfo = new FileInfo(fullPath);
return IsExcluded(fileInfo, _filters) ? new NotFoundFileInfo(subpath) : new PhysicalFileInfo(fileInfo);
}
async Task<String?> DownloadFile(String subpath, String fullPath)
{
var span = DefaultSpan.Current;
var svrs = GetServers?.Invoke() ?? Servers;
if (svrs != null && svrs.Length != 0)
{
foreach (var item in svrs)
{
try
{
var url = subpath.Replace("\\", "/");
url = item.Contains("{0}") ? item.Replace("{0}", url) : item.TrimEnd("/") + url.EnsureStart("/");
span?.AppendTag(url);
XTrace.WriteLine("下载文件：{0}", url);
// 先下载到临时目录，避免出现下载半截的情况
var tmp = Path.GetTempFileName();
{
using var fs = new FileStream(tmp, FileMode.OpenOrCreate);
using var client = new HttpClient { Timeout = Timeout };
using var rs = await client.GetStreamAsync(url);
rs.CopyTo(fs);
fs.Flush();
fs.SetLength(fs.Position);
}
// 移动临时文件到最终目录
fullPath.EnsureDirectory(true);
File.Move(tmp, fullPath, true);
// 修改脚本文件中的Url
var target = TargetServer;
if (target.IsNullOrEmpty())
{
target = NewLife.Setting.Current.ServiceAddress?.Split(",").FirstOrDefault();
if (!target.IsNullOrEmpty()) target = target.EnsureEnd("/files/");
}
if (!target.IsNullOrEmpty() && fullPath.EndsWithIgnoreCase(".sh", ".bat"))
{
var txt = File.ReadAllText(fullPath);
var txt2 = txt.Replace(item.EnsureEnd("/"), target.EnsureEnd("/"));
if (txt != txt2) File.WriteAllText(fullPath, txt2);
}
XTrace.WriteLine("下载文件完成：{0}", fullPath);
//fi = fullPath.AsFile();
return fullPath;
}
catch (Exception ex)
{
span?.SetError(ex, null);
XTrace.WriteLine(ex.Message);
}
}
}
return null;
}
/// <summary>
/// 是否存在
/// </summary>
/// <param name="fileInfo"></param>
/// <param name="filters"></param>
/// <returns></returns>
public static Boolean IsExcluded(FileSystemInfo fileInfo, ExclusionFilters filters)
{
if (filters == ExclusionFilters.None) return false;
return fileInfo.Name.StartsWith(".", StringComparison.Ordinal) && (filters & ExclusionFilters.DotPrefixed) != 0 ||
fileInfo.Exists && (
(fileInfo.Attributes & FileAttributes.Hidden) != 0 && (filters & ExclusionFilters.Hidden) != 0 ||
(fileInfo.Attributes & FileAttributes.System) != 0 && (filters & ExclusionFilters.System) != 0
);
}
/// <summary>
/// 获取文件内容
/// </summary>
/// <param name="subpath"></param>
/// <returns></returns>
public IDirectoryContents GetDirectoryContents(String subpath)
{
try
{
if (subpath == null || HasInvalidPathChars(subpath)) return NotFoundDirectoryContents.Singleton;
subpath = subpath.TrimStart(_pathSeparators);
if (Path.IsPathRooted(subpath)) return NotFoundDirectoryContents.Singleton;
using var span = Tracer?.NewSpan(nameof(GetDirectoryContents), subpath);
var fullPath = GetFullPath(subpath);
// 下载信息文件
var svrs = GetServers?.Invoke() ?? Servers;
if (!IndexInfoFile.IsNullOrEmpty() && svrs != null && svrs.Length > 0)
{
var fi = fullPath.CombinePath(IndexInfoFile).GetBasePath().AsFile();
if (!fi.Exists)
fi = DownloadDirectory(subpath, fi.FullName, svrs).Result?.AsFile();
else if (fi.LastWriteTime.AddDays(1) < DateTime.Now)
_ = Task.Run(() => DownloadDirectory(subpath, fi.FullName, svrs));
}
return fullPath == null || !Directory.Exists(fullPath)
? NotFoundDirectoryContents.Singleton
: new CacheDirectoryContents(fullPath, _filters) { IndexInfoFile = IndexInfoFile };
}
catch (DirectoryNotFoundException) { }
catch (IOException) { }
return NotFoundDirectoryContents.Singleton;
}
async Task<String?> DownloadDirectory(String subpath, String fullPath, String[] svrs)
{
var span = DefaultSpan.Current;
foreach (var item in svrs)
{
try
{
var url = subpath.Replace("\\", "/");
url = item.Contains("{0}") ? item.Replace("{0}", url) : item.TrimEnd("/") + url.EnsureStart("/");
span?.AppendTag(url);
XTrace.WriteLine("下载目录：{0}", url);
using var client = new HttpClient { Timeout = Timeout };
var html = await client.GetStringAsync(url);
var links = Link.Parse(html, url);
var list = links.Select(e => new FileInfoModel
{
Name = HttpUtility.UrlDecode(e.FullName + ""),
LastModified = e.Time.Year > 2000 ? e.Time : DateTime.Now,
Exists = true,
IsDirectory = false,
}).ToList();
var csv = new CsvDb<FileInfoModel> { FileName = fullPath };
csv.Write(list, false);
XTrace.WriteLine("下载目录完成：{0}", fullPath);
return fullPath;
}
catch (Exception ex)
{
span?.SetError(ex, null);
XTrace.WriteLine("下载目录出错：{0}", ex.Message);
}
}
return null;
}
/// <summary>
/// 监控文件改变
/// </summary>
/// <param name="filter"></param>
/// <returns></returns>
public IChangeToken Watch(String filter) => NullChangeToken.Singleton;
internal static Boolean HasInvalidPathChars(String path) => path.IndexOfAny(_invalidFileNameChars) != -1;
private static readonly Char[] _invalidFileNameChars = (from c in Path.GetInvalidFileNameChars()
where c != Path.DirectorySeparatorChar && c != Path.AltDirectorySeparatorChar
select c).ToArray();
internal static Boolean PathNavigatesAboveRoot(String path)
{
var stringTokenizer = new StringTokenizer(path, _pathSeparators);
var num = 0;
foreach (var item in stringTokenizer)
{
if (item.Equals(".") || item.Equals("")) continue;
if (item.Equals(".."))
{
num--;
if (num == -1) return true;
}
else
num++;
}
return false;
}
}
|