Error

Error is an .NET library for structured error and result management. It provides a consistent, extensible, and type-safe way to represent, build, and propagate errors in your applications and APIs.

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Table of Contents

• Features
• Installation
• Usage
  • Basic Error Creation
  • Error with Formatting
  • Using ErrorBuilder (Fluent API)
  • Using ErrorBuilder with Direct Text
  • Exception Safety
• Project Structure
• Contributing
• License
• Author

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Features

• Strongly-typed error representation using C# records and enums
• Fluent ErrorBuilder for easy and safe error construction
• Integration with ASP.NET Core via ProblemDetails
• Support for error severity levels (Error, Warning, Info)
• Format string validation with runtime safety and caller info in exceptions
• Unit tested and .NET 8 ready

Installation

Add a reference to the Lukdrasil.Error project or package in your solution:

If using as a project reference

<PackageReference Include="Lukdrasil.Error" Version="x.y.z" />

Or clone the repository and add the project to your solution.

Usage

Basic Error Creation

using Lukdrasil.Error;

var error = new Error("ERR001", ErrorSeverity.Error, "Something went wrong");
var problemDetails = error.ToProblemDetails();

Error with Formatting

using Lukdrasil.Error;

var error = new Error(
    "ERR_FORMAT",
    ErrorSeverity.Warning,
    string.Format("Invalid value for field '{0}' at line '{1}'", "Name", 42)
);

Using ErrorBuilder (Fluent API)

using Lukdrasil.Error;

var error = new ErrorBuilder()
    .WithCode("ERR_USER")
    .WithSeverity(ErrorSeverity.Error)
    .WithDescription("User with id {0} not found", userId)
    .Build();

Using ErrorBuilder with Direct Text

using Lukdrasil.Error;

var error = new ErrorBuilder()
    .WithCode("ERR_CUSTOM")
    .WithDescriptionText("A custom error occurred.")
    .Build();

Exception Safety

If you use a format string with placeholders but do not provide arguments, the builder will throw an ArgumentException with caller info:

using Lukdrasil.Error;

var error = new ErrorBuilder()
    .WithDescription("Field {0} is required");

error.Build(); // Throws ArgumentException with caller info

Project Structure

• Error - Main error record with code, severity, and description
• ErrorBuilder - Fluent builder for safe error creation
• BaseError - Abstract base for custom error types
• ErrorSeverity - Enum for error levels
• Unit tests in Error.Tests

Contributing

Contributions are welcome! Please open issues or submit pull requests for any features, bugfixes, or improvements.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/YourFeature)
3. Commit your changes (git commit -am 'Add new feature')
4. Push to the branch (git push origin feature/YourFeature)
5. Open a pull request

License

This project is licensed under the MIT License. See the LICENSE file for details.