uSignIn.CommonSettings 10.2.1

uSignIn.CommonSettings

uSignIn.CommonSettings is a robust C# class library designed to centralize configuration management and provide essential validation logic for the uSignIn ecosystem. It acts as a strongly-typed wrapper around appsettings.json, ensuring consistency and safety across your projects.

Features

• Centralized Configuration: Strongly-typed access to common settings like API URLs, frontend endpoints, and platform-specific configurations (Android/iOS).
• Request Freshness Validation: Built-in logic to validate request timestamps, helping to prevent replay attacks by enforcing a configurable time window.
• History Tracking: Generic History DTOs and extensions to easily track and retrieve the latest values from a time-ordered sequence.
• Platform Support: dedicated configuration sections for Android and iOS specific settings (Scheme, Host).

Installation

Install the NuGet package via the .NET CLI:

dotnet add package uSignIn.CommonSettings

Or via the NuGet Package Manager in Visual Studio.

Configuration

Add the following Settings section to your appsettings.json. Adjust the values to match your environment.

{
  "Settings": {
    "BaseUrl": "https://api.yourdomain.com",
    "FrontendUrl": "https://app.yourdomain.com",
    "RequestTimeSpanRangeInMilliseconds": "-120000:120000",
    "Android": {
      "Scheme": "usignin",
      "Host": "callback"
    },
    "iOS": {
      "Scheme": "usignin",
      "Host": "callback"
    }
  }
}

Configuration Breakdown

• BaseUrl: The root URL for your backend API.
• FrontendUrl: The root URL for your frontend application.
• RequestTimeSpanRangeInMilliseconds: Defines the valid time window for requests relative to the server time.
  • Format: "LowerLimit:UpperLimit" (in milliseconds). Both limits are offsets of the request timestamp from server time: a negative limit lies in the past, a positive limit in the future. LowerLimit must be less than or equal to UpperLimit.
  • Example "-120000:120000" means a request timestamp is valid if it is between 2 minutes in the past and 2 minutes in the future.
  • Asymmetric windows are supported: "-600000:1000" tolerates 10 minutes of age but only 1 second of future clock skew.
  • Values are parsed with the invariant culture, so the same configuration behaves identically on every host regardless of locale. Do not use group separators — "-60.000" is read as -60 milliseconds, not -60000.
  • If the value is missing or malformed, a critical message is logged and the default "-180000000:120000" (50 hours of age, 2 minutes of future skew) is used.
• Android / iOS: Platform-specific settings used for deep linking or redirects. Optional — when a section is absent a warning is logged and Scheme/Host are empty strings rather than null.

Usage

1. Registering the services

Call AddCommonSettingsServices() on your service collection during startup. It registers SettingsService as a singleton and is safe to call more than once.

using uSignIn.CommonSettings;

builder.Services.AddCommonSettingsServices();

SettingsService reads and validates configuration when it is first constructed, throwing InvalidOperationException if Settings:BaseUrl or Settings:FrontendUrl is missing or is not an absolute URL.

2. Settings Service

Inject SettingsService into your classes.

using uSignIn.CommonSettings.Settings;

public class MyService
{
    private readonly SettingsService _settings;

    public MyService(SettingsService settings)
    {
        _settings = settings;
    }

    public void DoWork()
    {
        // Access URLs
        var apiUrl = _settings.BaseUri;
        
        // Access Platform Settings
        var androidScheme = _settings.Android.Scheme;
    }

    public void ValidateRequest(DateTimeOffset requestTime)
    {
        // Check if the request is within the allowed time window
        if (!_settings.IsFresh(requestTime))
        {
            throw new InvalidOperationException("Request is expired or invalid.");
        }
    }
}

3. History Tracking

Use the History DTO and HistoryExtensions to manage historical data.

using uSignIn.CommonSettings.DTOs;

var loginHistory = new List>
{
    new History { Value = "Login_Attempt_1", TimeStamp = DateTimeOffset.UtcNow.AddMinutes(-10) },
    new History { Value = "Login_Success", TimeStamp = DateTimeOffset.UtcNow }
};

// Get the value of the most recent entry
string? latestStatus = loginHistory.LatestValue(); // Returns "Login_Success"

// Get the entire latest record
History? latestRecord = loginHistory.LatestRecord();

Contributing

We welcome contributions! If you find a bug or have an idea for improvement, please submit an issue or a pull request on our GitHub repository.

License

This project is licensed under the GNU GENERAL PUBLIC LICENSE.

Happy coding! 🚀🌐📚