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Saturday, 14 September 2024
我已经 博客上写了很多 我如何使用 Markdown 来创建博客文章的时数; 我非常喜欢这个方法, 但有一个主要的缺点, 这意味着我必须完成一个完整的 Docker 构建周期来更新一个文章 。 我在创造更多功能时,这是FFE, 然后我又在博客上写了这些功能, 但现在这已经相当有限了。 我希望能够更新我的博客文章, 所以现在我在我的博客上增加了一个新的功能, 让我可以这样做。
我指的是这个生命周期; 又是相当简单但又很酷的(以超级怪胎的方式!) )
所以很简单
这允许我继续在当地使用骑士来创建博客文章(将来我可能会让网站本身也出现这种情况), 所有翻译都动态地出现在网站本身,
graph LR;
A(Write new .md file)--> B[Upload using WinSCP];
B --> C[New File Detected];
C --> D(Process Markdown);
D --> E[Insert into Database];
E --> F(Kick off translations);
F-->G[Add Translations to Database];
G-->H[/Update Website/];
这个代码是另一个 IHostedService,这一次它使用 FileSystemWatcher 类可以查看新文件的目录。 当检测到一个新文件时, 它会读取文件, 处理并插入到数据库中 。 如果我删除一个英文职位,它也将删除该职位的所有译文。
整个代码都在下面 但我会把它分解一下
using Mostlylucid.Config.Markdown;
using Polly;
using Serilog.Events;
namespace Mostlylucid.Blog.WatcherService;
public class MarkdownDirectoryWatcherService(MarkdownConfig markdownConfig, IServiceScopeFactory serviceScopeFactory,
ILogger<MarkdownDirectoryWatcherService> logger)
: IHostedService
{
private Task _awaitChangeTask = Task.CompletedTask;
private FileSystemWatcher _fileSystemWatcher;
public Task StartAsync(CancellationToken cancellationToken)
{
_fileSystemWatcher = new FileSystemWatcher
{
Path = markdownConfig.MarkdownPath,
NotifyFilter = NotifyFilters.FileName | NotifyFilters.LastWrite | NotifyFilters.CreationTime |
NotifyFilters.Size,
Filter = "*.md", // Watch all markdown files
IncludeSubdirectories = true // Enable watching subdirectories
};
// Subscribe to events
_fileSystemWatcher.EnableRaisingEvents = true;
_awaitChangeTask = Task.Run(()=> AwaitChanges(cancellationToken));
logger.LogInformation("Started watching directory {Directory}", markdownConfig.MarkdownPath);
return Task.CompletedTask;
}
public Task StopAsync(CancellationToken cancellationToken)
{
// Stop watching
_fileSystemWatcher.EnableRaisingEvents = false;
_fileSystemWatcher.Dispose();
Console.WriteLine($"Stopped watching directory: {markdownConfig.MarkdownPath}");
return Task.CompletedTask;
}
private async Task AwaitChanges(CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
var fileEvent = _fileSystemWatcher.WaitForChanged(WatcherChangeTypes.All);
if (fileEvent.ChangeType == WatcherChangeTypes.Changed ||
fileEvent.ChangeType == WatcherChangeTypes.Created)
{
await OnChangedAsync(fileEvent);
}
else if (fileEvent.ChangeType == WatcherChangeTypes.Deleted)
{
OnDeleted(fileEvent);
}
else if (fileEvent.ChangeType == WatcherChangeTypes.Renamed)
{
}
}
}
private async Task OnChangedAsync(WaitForChangedResult e)
{
if (e.Name == null) return;
var activity = Log.Logger.StartActivity("Markdown File Changed {Name}", e.Name);
var retryPolicy = Policy
.Handle<IOException>() // Only handle IO exceptions (like file in use)
.WaitAndRetryAsync(5, retryAttempt => TimeSpan.FromMilliseconds(500 * retryAttempt),
(exception, timeSpan, retryCount, context) =>
{
activity?.Activity?.SetTag("Retry Attempt", retryCount);
// Log the retry attempt
logger.LogWarning("File is in use, retrying attempt {RetryCount} after {TimeSpan}", retryCount, timeSpan);
});
try
{
var fileName = e.Name;
var isTranslated = Path.GetFileNameWithoutExtension(e.Name).Contains(".");
var language = MarkdownBaseService.EnglishLanguage;
var directory = markdownConfig.MarkdownPath;
if (isTranslated)
{
language = Path.GetFileNameWithoutExtension(e.Name).Split('.').Last();
fileName = Path.GetFileName(fileName);
directory = markdownConfig.MarkdownTranslatedPath;
}
var filePath = Path.Combine(directory, fileName);
var scope = serviceScopeFactory.CreateScope();
var markdownBlogService = scope.ServiceProvider.GetRequiredService<IMarkdownBlogService>();
// Use the Polly retry policy for executing the operation
await retryPolicy.ExecuteAsync(async () =>
{
var blogModel = await markdownBlogService.GetPage(filePath);
activity?.Activity?.SetTag("Page Processed", blogModel.Slug);
blogModel.Language = language;
var blogService = scope.ServiceProvider.GetRequiredService<IBlogService>();
await blogService.SavePost(blogModel);
if (language == MarkdownBaseService.EnglishLanguage)
{
var translateService = scope.ServiceProvider.GetRequiredService<BackgroundTranslateService>();
await translateService.TranslateForAllLanguages(
new PageTranslationModel(){OriginalFileName = filePath, OriginalMarkdown = blogModel.Markdown,Persist = true});
}
activity?.Activity?.SetTag("Page Saved", blogModel.Slug);
});
activity?.Complete();
}
catch (Exception exception)
{
activity?.Complete(LogEventLevel.Error, exception);
}
}
private void OnDeleted(WaitForChangedResult e)
{
if(e.Name == null) return;
var isTranslated = Path.GetFileNameWithoutExtension(e.Name).Contains(".");
var language = MarkdownBaseService.EnglishLanguage;
var slug = Path.GetFileNameWithoutExtension(e.Name);
if (isTranslated)
{
var name = Path.GetFileNameWithoutExtension(e.Name).Split('.');
language = name.Last();
slug = name.First();
}
else
{
var translatedFiles = Directory.GetFiles(markdownConfig.MarkdownTranslatedPath, $"{slug}.*.*");
_fileSystemWatcher.EnableRaisingEvents = false;
foreach (var file in translatedFiles)
{
File.Delete(file);
}
_fileSystemWatcher.EnableRaisingEvents = true;
}
var scope = serviceScopeFactory.CreateScope();
var blogService = scope.ServiceProvider.GetRequiredService<IBlogService>();
blogService.Delete(slug, language);
}
private void OnRenamed(object sender, RenamedEventArgs e)
{
Console.WriteLine($"File renamed: {e.OldFullPath} to {e.FullPath}");
}
}
所以,它所做的就是启动一个新的任务 使用 FileSystemWatcher 里面是 StartAsync 方法。 在一个 IHostedService 这是 ASP.NET 核心框架启动服务的切入点。
private FileSystemWatcher _fileSystemWatcher;
public Task StartAsync(CancellationToken cancellationToken)
{
_fileSystemWatcher = new FileSystemWatcher
{
Path = markdownConfig.MarkdownPath,
NotifyFilter = NotifyFilters.FileName | NotifyFilters.LastWrite | NotifyFilters.CreationTime |
NotifyFilters.Size,
Filter = "*.md", // Watch all markdown files
IncludeSubdirectories = true // Enable watching subdirectories
};
// Subscribe to events
_fileSystemWatcher.EnableRaisingEvents = true;
_awaitChangeTask = Task.Run(()=> AwaitChanges(cancellationToken));
logger.LogInformation("Started watching directory {Directory}", markdownConfig.MarkdownPath);
return Task.CompletedTask;
}
我有一个本地任务 给服务局 我点燃改变循环
private Task _awaitChangeTask = Task.CompletedTask;
_awaitChangeTask = Task.Run(()=> AwaitChanges(cancellationToken));
这很重要, 否则这就会成为屏障, 您需要确保这在背景中进行( 问我如何知道这件事 ) 。
我们在这里设置了一个 FileSystemWatcher 来聆听我的 Markdown 目录中的事件( 基于稍后会看到的原因, 设置为主机目录 )!
_fileSystemWatcher = new FileSystemWatcher
{
Path = markdownConfig.MarkdownPath,
NotifyFilter = NotifyFilters.FileName | NotifyFilters.LastWrite | NotifyFilters.CreationTime |
NotifyFilters.Size,
Filter = "*.md", // Watch all markdown files
IncludeSubdirectories = true // Enable watching subdirectories
};
// Subscribe to events
_fileSystemWatcher.EnableRaisingEvents = true;
你可以看到我在看着 FileName, LastWrite, CreationTime 和 Size 变化。 这是因为我想知道文件是创建、更新还是删除。
我也有一个 Filter 设置为 *.md 所以我只看标记文件, 并指定我也要看子目录( 用于翻译) 。
在这个代码中,我有一个更改循环,等待文件系统的更改。 注意,你也可以只是 挂在这里的变化事件 在这里,但我觉得这 感觉干净。
private async Task AwaitChanges(CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
var fileEvent = _fileSystemWatcher.WaitForChanged(WatcherChangeTypes.All);
if (fileEvent.ChangeType == WatcherChangeTypes.Changed ||
fileEvent.ChangeType == WatcherChangeTypes.Created)
{
await OnChangedAsync(fileEvent);
}
else if (fileEvent.ChangeType == WatcherChangeTypes.Deleted)
{
OnDeleted(fileEvent);
}
else if (fileEvent.ChangeType == WatcherChangeTypes.Renamed)
{
}
}
}
很简单,它所做的就是等待一个变化事件,然后拨打 OnChangedAsync 方法。 如果删除文件,它调用 OnDeleted 方法。
这就是"魔力"发生的地方 它所做的就是倾听改变事件。 然后用我的管道处理标记文件( 以获得 HTML 分类、 日期、 标题等) 并将其输入数据库 。 它检测文件是否用英文(所以我写了:), 见见 此员额 这是如何运作的。
await retryPolicy.ExecuteAsync(async () =>
{
var blogModel = await markdownBlogService.GetPage(filePath);
activity?.Activity?.SetTag("Page Processed", blogModel.Slug);
blogModel.Language = language;
var blogService = scope.ServiceProvider.GetRequiredService<IBlogService>();
await blogService.SavePost(blogModel);
if (language == MarkdownBaseService.EnglishLanguage)
{
var translateService = scope.ServiceProvider.GetRequiredService<BackgroundTranslateService>();
await translateService.TranslateForAllLanguages(
new PageTranslationModel(){OriginalFileName = filePath, OriginalMarkdown = blogModel.Markdown,Persist = true});
}
activity?.Activity?.SetTag("Page Saved", blogModel.Slug);
});
请注意,我使用 Polly 在此处理文件处理; 这样可以确保文件在试图处理前真正上传/ 保存过 。
var retryPolicy = Policy
.Handle<IOException>() // Only handle IO exceptions (like file in use)
.WaitAndRetryAsync(5, retryAttempt => TimeSpan.FromMilliseconds(500 * retryAttempt),
(exception, timeSpan, retryCount, context) =>
{
activity?.Activity?.SetTag("Retry Attempt", retryCount);
// Log the retry attempt
logger.LogWarning("File is in use, retrying attempt {RetryCount} after {TimeSpan}", retryCount, timeSpan);
});
我也用过 SerilogTracing 帮助我找到任何问题, 当它更容易“生产”的时候(I) 有条款的,有条款的, 也上那个!) )
flowchart LR
A[Start OnChangedAsync] --> B{Is e.Name null}
B -- Yes --> C[Return]
B -- No --> D[Start Activity and Set File Parameters]
D --> E[Execute retryPolicy]
E --> F[Process and Save Markdown File]
F --> G{Is language English}
G -- Yes --> H[Kick off Translation]
G -- No --> I[Skip Translation]
H --> J[Complete Activity]
I --> J
J --> K[Handle Errors]
private async Task OnChangedAsync(WaitForChangedResult e)
{
if (e.Name == null) return;
var activity = Log.Logger.StartActivity("Markdown File Changed {Name}", e.Name);
var retryPolicy = Policy
.Handle<IOException>() // Only handle IO exceptions (like file in use)
.WaitAndRetryAsync(5, retryAttempt => TimeSpan.FromMilliseconds(500 * retryAttempt),
(exception, timeSpan, retryCount, context) =>
{
activity?.Activity?.SetTag("Retry Attempt", retryCount);
// Log the retry attempt
logger.LogWarning("File is in use, retrying attempt {RetryCount} after {TimeSpan}", retryCount, timeSpan);
});
try
{
var fileName = e.Name;
var isTranslated = Path.GetFileNameWithoutExtension(e.Name).Contains(".");
var language = MarkdownBaseService.EnglishLanguage;
var directory = markdownConfig.MarkdownPath;
if (isTranslated)
{
language = Path.GetFileNameWithoutExtension(e.Name).Split('.').Last();
fileName = Path.GetFileName(fileName);
directory = markdownConfig.MarkdownTranslatedPath;
}
var filePath = Path.Combine(directory, fileName);
var scope = serviceScopeFactory.CreateScope();
var markdownBlogService = scope.ServiceProvider.GetRequiredService<IMarkdownBlogService>();
// Use the Polly retry policy for executing the operation
await retryPolicy.ExecuteAsync(async () =>
{
var blogModel = await markdownBlogService.GetPage(filePath);
activity?.Activity?.SetTag("Page Processed", blogModel.Slug);
blogModel.Language = language;
var blogService = scope.ServiceProvider.GetRequiredService<IBlogService>();
await blogService.SavePost(blogModel);
if (language == MarkdownBaseService.EnglishLanguage)
{
var translateService = scope.ServiceProvider.GetRequiredService<BackgroundTranslateService>();
await translateService.TranslateForAllLanguages(
new PageTranslationModel(){OriginalFileName = filePath, OriginalMarkdown = blogModel.Markdown,Persist = true});
}
activity?.Activity?.SetTag("Page Saved", blogModel.Slug);
});
activity?.Complete();
}
catch (Exception exception)
{
activity?.Complete(LogEventLevel.Error, exception);
}
}
这很简单, 它只是检测一个文件被删除后从数据库中移除; 我使用它作为预防白痴的措施, 我习惯于上传文章, 然后立即看到它们有错误 。 您可以看到它测试来查看文件是否被翻译,如果是,则删除文件的所有译文。
flowchart LR
A[Start OnDeleted] --> B{Is e.Name null}
B -- Yes --> C[Return]
B -- No --> D[Start Activity and Set Parameters: isTranslated, language, slug]
D --> E{Is file translated}
E -- Yes --> F[Set language and slug for translation]
E -- No --> G[Delete all translated files]
F --> H[Create DI Scope and Get IBlogService]
G --> H
H --> I[Delete Post from Database]
I --> J[Complete Activity]
J --> K[Handle Errors if any]
private void OnDeleted(WaitForChangedResult e)
{
if (e.Name == null) return;
var activity = Log.Logger.StartActivity("Markdown File Deleting {Name}", e.Name);
try
{
var isTranslated = Path.GetFileNameWithoutExtension(e.Name).Contains(".");
var language = MarkdownBaseService.EnglishLanguage;
var slug = Path.GetFileNameWithoutExtension(e.Name);
if (isTranslated)
{
var name = Path.GetFileNameWithoutExtension(e.Name).Split('.');
language = name.Last();
slug = name.First();
}
else
{
var translatedFiles = Directory.GetFiles(markdownConfig.MarkdownTranslatedPath, $"{slug}.*.*");
_fileSystemWatcher.EnableRaisingEvents = false;
foreach (var file in translatedFiles)
{
File.Delete(file);
}
_fileSystemWatcher.EnableRaisingEvents = true;
}
var scope = serviceScopeFactory.CreateScope();
var blogService = scope.ServiceProvider.GetRequiredService<IBlogService>();
blogService.Delete(slug, language);
activity?.Activity?.SetTag("Page Deleted", slug);
activity?.Complete();
logger.LogInformation("Deleted blog post {Slug} in {Language}", slug, language);
}
catch (Exception exception)
{
activity?.Complete(LogEventLevel.Error, exception);
logger.LogError("Error deleting blog post {Slug}", e.Name);
}
}
我用 WinSCP 将文件上传到我的网站 。 我可以做一个“ 同步” 来上传任何标记文件, 然后我的服务会把它们添加到 DB 中 。 这是 FileSystemWatcher 正在观看。 未来我还会增加一个图像上传能力, 在那里,我会增加一些预处理 和处理更大的文件。
所以,这是一个很简单的方法, 在我的网站上添加新的博客文章, 而不必做一个完整的建设周期。 这篇文章中,我教人如何使用 FileSystemWatcher 来检测对目录的更改并处理这些更改。 我还教过如何使用 Polly 处理重试和 Serilog 来记录进程。
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