FileValidation.Toolkit 1.0.1

FileValidation.Toolkit

Configurable file validation package for .NET Framework-compatible and modern .NET applications.

Features

• Enable or disable each validation rule from configuration
• Validate extensions, dangerous extensions, duplicate extensions, file names, file sizes, empty files, MIME types, file signatures, ZIP archives, and basic image dimensions
• Supports appsettings.json through IConfiguration
• Supports web.config / app.config through ConfigurationManager
• Extensible with custom IFileValidationRule and optional IFileThreatScanner

appsettings.json

{
  "FileValidation": {
    "Enabled": true,
    "MaxFileSizeBytes": 10485760,
    "AllowedExtensions": [ ".pdf", ".docx", ".xlsx", ".png", ".jpg" ],
    "BlockedExtensions": [ ".exe", ".bat", ".cmd", ".js", ".vbs", ".ps1" ],
    "Rules": {
      "Extension": { "Enabled": true },
      "BlockedExtension": { "Enabled": true },
      "MimeType": { "Enabled": false },
      "FileSignature": { "Enabled": true },
      "FileSize": { "Enabled": true },
      "FileName": { "Enabled": true },
      "DuplicateExtension": { "Enabled": true },
      "EmptyFile": { "Enabled": true },
      "Archive": { "Enabled": true },
      "Image": { "Enabled": true },
      "ThreatScan": { "Enabled": false }
    },
    "Archive": {
      "MaxEntries": 100,
      "MaxUncompressedSizeBytes": 52428800,
      "BlockNestedArchives": true
    },
    "Image": {
      "MaxWidth": 8000,
      "MaxHeight": 8000
    }
  }
}

using FileValidation.Toolkit.DependencyInjection;

builder.Services.AddFileValidation(builder.Configuration);

var result = await validator.ValidateAsync(
    new FileValidationRequest(fileStream, fileName, contentType),
    cancellationToken);

if (!result.IsValid)
{
    foreach (var error in result.Errors)
    {
        Console.WriteLine($"{error.Code}: {error.Message}");
    }
}

web.config / app.config

<appSettings>
  <add key="FileValidation:Enabled" value="true" />
  <add key="FileValidation:MaxFileSizeBytes" value="10485760" />
  <add key="FileValidation:AllowedExtensions" value=".pdf,.docx,.xlsx,.png,.jpg" />
  <add key="FileValidation:BlockedExtensions" value=".exe,.bat,.cmd,.js,.vbs,.ps1" />
  <add key="FileValidation:Rules:Extension:Enabled" value="true" />
  <add key="FileValidation:Rules:FileSignature:Enabled" value="true" />
  <add key="FileValidation:Rules:Archive:Enabled" value="true" />
  <add key="FileValidation:Archive:MaxEntries" value="100" />
</appSettings>

using FileValidation.Toolkit;
using FileValidation.Toolkit.Configuration;

var options = WebConfigurationFileValidationOptionsLoader.FromWebConfiguration();
var validator = new FileValidator(options);

Target frameworks

The package targets netstandard2.0 and net8.0. .NET Framework applications can consume the netstandard2.0 asset when they target a compatible framework version.