A Result pattern library for .NET.
MIT License
Reditus, is a Result pattern library for every .NET application.
You can install Reditus with NuGet:
Install-Package Reditus
Result objects can hold values or simply be used as flow state control. The values can be anything. A class, a value-type, a struct, anything.
Typically, the Result
class is being used by methods that don't return a value.
var result = Result.Success();
var result = Result.Fail();
// the error can also hold a message
var error = new Error("An error occured.");
var result = Result.Fail(error);
// the error can also hold an exception
var error = new Error("An error occured.", new Exception());
var result = Result.Fail(error);
An example usage of the Result
class.
public async Task<Result> ExecuteJob()
{
try
{
var jobId = ExecuteCleanupJob();
if (jobId == 0)
{
// create an Error indicating the reason of failure
var error = new Error("Cleanup job was not executed.");
return Result.Fail(error);
}
return Result.Success();
}
catch (Exception ex)
{
// create an Error and attach the exception
var error = new Error("An unexpected error occured while trying execute Cleanup job.", ex);
return Result.Fail(error);
}
}
The Result<T>
class is being used by methods that return a value.
var result = Result<int>.Success(1);
var result = Result<int>.Fail();
// the error can also hold a message
var error = new Error("An error occured.");
var result = Result.Fail(error);
// the error can also hold an exception
var error = new Error("An error occured.", new Exception());
var result = Result<int>.Fail(error);
An example usage of the Result<T>
class.
public async Task<Result<int>> ExecuteJob()
{
try
{
var jobId = ExecuteCleanupJob();
if (jobId == 0)
{
// create an Error indicating the reason of failure
var error = new Error("Cleanup job was not executed.");
return Result<int>.Fail(error);
}
return Result<int>.Success(jobId);
}
catch (Exception ex)
{
// create an Error and attach the exception
var error = new Error("An unexpected error occured while trying execute Cleanup job.", ex);
return Result<int>.Fail(error);
}
}
A Result
holds certain information about itself.
var result = Result.Success();
result.IsSuccessful // true
result.IsFailed // false
result.Error // throws InvalidOperationException as the result is not in a failed state
var result = Result.Fail();
result.IsSuccessful // false
result.IsFailed // true
result.Error // Error instance
When the Result<T>
holds a return value.
var result = Result<int>.Success(1);
result.IsSuccessful // true
result.IsFailed // false
result.Value // 1
result.Error // throws InvalidOperationException as the result is not in a fail state
var result = Result<int>.Fail();
result.IsSuccessful // false
result.IsFailed // true
result.Value // throws InvalidOperationException as the result is not in a success state
result.Error // IError instance
You can introduce your very own Error classes by extending the existing one.
The below custom NotFoundError
class is being used when an application might need to return a NotFound 404 response.
public interface IHttpError : IError
{
public HttpStatusCode HttpStatusCode { get; }
}
public sealed class NotFoundError : Error, IHttpError
{
public HttpStatusCode HttpStatusCode => HttpStatusCode.NotFound;
public NotFoundError(string message)
: base(message)
{
}
}
An example of the above custom Error
class.
public async Task<Result<IEnumerable<Project>>> GetProjects()
{
try
{
var projects = await GetProjects();
if (!projects.Any())
{
var error = new NotFoundError("The request resource was not found."); // <-- the new NotFoundError Error class
return Result<IEnumerable<Project>>.Fail(error);
}
return Result<IEnumerable<Project>>.Success(jobId);
}
catch (Exception ex)
{
// create an Error and attach the exception
var error = new Error("An unexpected error occured while trying execute Cleanup job.", ex);
return Result<IEnumerable<Project>>.Fail(error);
}
}
The Error
class provides 2 constructors, so you are free to use whichever suits your needs
best. See definition