FluentResults

Introduction to FluentResults

FluentResults is a lightweight .NET library designed to address a common programming challenge by providing a mechanism to indicate the success or failure of an operation without resorting to throwing or using exceptions. This innovative library allows developers to handle error management in a more functional programming style, making code cleaner and easier to follow. You can readily incorporate FluentResults into your projects by installing it via NuGet.

Key Features

FluentResults offers a host of features beneficial for developers, including:

• A generalized container that can be used in various contexts such as ASP.NET MVC/WebApi, WPF, and Domain-Driven Design (DDD) domain models.
• The capability to store multiple errors in one Result object, instead of limiting to just string error messages.
• Object-oriented design of error and success objects, allowing for more informative feedback.
• The possibility to store the root cause and a hierarchy of error chains to trace back issues.
• Compatibility with modern .NET frameworks including .NET Standard, .NET Core, .NET 5+, and the full .NET Framework.
• Enhance FluentAssertions extensions for asserting FluentResult objects decisively.
• Integration guidance with comprehensive code samples.

Why Choose Result Objects Over Exceptions

The pattern of using result objects to indicate operation success or failure originates from functional programming languages. FluentResults brings this pattern into the .NET/C# ecosystem. It is advantageous in scenarios where using exceptions for flow control could lead to cluttered code. Understanding when to use this pattern effectively can be facilitated by recommended articles and best practices highlighted within the documentation.

Crafting Results

Developers can easily create result objects using FluentResults' straightforward API:

• To indicate a successful operation, simply call Result.Ok().
• For failed operations, you can utilize Result.Fail() with either simple string messages or more complex error objects that store deeper information related to the failure.
• Results can be extended to include specific data types, allowing value storage alongside success or failure indications.

Handling Results

Once you receive a result object from a method, you must process it to check whether the operation was successful. The properties IsSuccess and IsFailed in the result object provide immediate insights. FluentResults also supports retrieving all reasons for success or failure, catering to nuanced error handling requirements.

Designing Rich Error and Success Messages

FluentResults promotes a richer, object-oriented approach to error and success messaging by adopting interfaces like IError and ISuccess. This approach encapsulates all relevant information in a single class, enabling customized success or error classes to be created by developers, offering superior flexibility and clarity for handling complex scenarios.

Advanced Features

FluentResults comes packed with additional functionalities to enhance error handling:

• Chain multiple error and success messages within a single result.
• Create results based on specific conditions using FailIf() and OkIf() methods, aiding readability and maintainability.
• Use the Try method for executing actions with automatic exception capture, transforming exceptions into result objects seamlessly.
• Store error root causes using CausedBy(...), making it easier to debug complex errors.
• Leverage metadata for additional context in error or success objects.
• Merge multiple results into one to simplify processing logic.
• Convert or transform between different result types effortlessly.
• Enable logging for result objects, with customizable log levels and contexts.
• Utilize implicit conversions for easier transitions between error messages and results.

.NET Compatibility and Resources

FluentResults supports various .NET frameworks and offers extensive documentation, samples, and best practices to guide developers in integrating and utilizing the library effectively. It ensures compatibility with modern frameworks and provides built-in extensions for popular libraries and tools, solidifying its utility in contemporary development environments.

Whether working on web applications, desktop software, or other environments, FluentResults equips developers with the tools to manage success and failure states coherently, leading to more robust and maintainable codebases.