UaDetector 0.1.4

UaDetector

A powerful user-agent parsing library inspired by device-detector.

UaDetector is a user-agent parsing library that identifies the browser, operating system, device, client, and even detects bots.

It is composed of several sub-parsers: OsParser, BrowserParser, ClientParser, and BotParser. Each can be used independently if only certain information is needed from the user-agent string.

Key Features

• Thread Safety: The parsers are stateless by design, making them fully thread-safe and dependency-injection friendly.
• Optimized for Performance: Uses compiled regular expressions and frozen dictionaries for faster pattern matching and lookup operations.
• Predefined Values: Static classes provide access to browser, operating system, and other related metadata. These include: OsNames, OsFamilies, OsPlatformTypes, BrowserNames, BrowserFamilies, BrowserEngines, BrandNames.
• Type-Safe Values: Certain values are represented by enums, making them suitable for database storage. These include: OsCode, BrowserCode, BrandCode, ClientType, DeviceType, BotCategory.
• Try-Parse Pattern: Parsers make use of the Try-Parse Pattern, returning a bool status and setting the out parameter to null on failure.

⚙️ Configuration

To use UaDetector, register it in Program.cs with the AddUaDetector method. To use a sub-parser, register it using its dedicated method: AddOsParser, AddBrowserParser, AddClientParser, or AddBotParser. All sub-parsers, except AddBotParser, can be configured via UaDetectorOptions using the Options pattern as shown below.

using UaDetector;

builder.Services.AddUaDetector(options =>
{
    // Custom configuration options
    // e.g., options.VersionTruncation = VersionTruncation.Major;
});

🚀 Quick Start

Each parser provides two TryParse methods: one that accepts only the user-agent string and another that accepts both the user-agent string and a collection of HTTP headers. For more accurate detection, it is recommended to provide the HTTP headers.

Tip: Avoid directly instantiating parsers. The first initialization of UaDetector (or its sub-parsers) takes a few seconds (around 1-3s). To avoid this one-time cost during runtime, register the service with dependency injection, as shown earlier. This way, the instantiation will happen at application startup.

[ApiController]
public class UaDetectorController : ControllerBase
{
    private readonly IUaDetector _uaDetector;

    public UaDetectorController(IUaDetector uaDetector)
    {
        _uaDetector = uaDetector;
    }

    [HttpGet]
    [Route("ua-detector")]
    public IActionResult GetUserAgentInfo()
    {
        var userAgent = HttpContext.Request.Headers.UserAgent.ToString();
        var headers = Request.Headers.ToDictionary(h => h.Key, h => h.Value.ToArray().FirstOrDefault());

        if (_uaDetector.TryParse(userAgent, headers, out var result))
        {
            return Ok(result);
        }
        
        return BadRequest("No matching user-agent information was found");
    }
}

The BotParser class provides an additional IsBot method to determine whether a user-agent string represents a bot.

using UaDetector.Parsers;

var botParser = new BotParser();
const string userAgent = "Mozilla/5.0 (compatible; Discordbot/2.0; +https://discordapp.com)";

if (botParser.IsBot(userAgent))
{
    Console.WriteLine("Bot detected");
}
else
{
    Console.WriteLine("No bot detected");
}

⚡ Benchmarks

The following benchmark compares the performance of other .NET user-agent parsing libraries.

The following benchmark measures the performance of different parsers within the library.

Note: For full documentation, visit the GitHub repository.