CatchAll 1.1.0

CatchAll

Centralize and simplify error handling in ASP.NET Core — result pattern and global exception middleware, configured in minutes.

Stop scattering try/catch blocks and HTTP status codes across your controllers. CatchAll gives you a clean Result pattern for expected errors and a global middleware for everything else — so your application always responds consistently.

Installation

dotnet add package CatchAll

Getting started

1. Define your errors

Errors are strongly typed and carry their own HTTP status code. Every AppError supports the following fields:

public sealed record UserNotFoundError() 
    : AppError(
        Name: "User not found",
        StatusCode: HttpStatusCode.NotFound,
        Code: "USER_NOT_FOUND",
        Detail: "No user was found with the provided ID"
    );
 
public sealed record UnauthorizedError() 
    : AppError(
        Name: "Unauthorized",
        StatusCode: HttpStatusCode.Unauthorized,
        Code: "UNAUTHORIZED"
    );

2. Return results from your services

public CatchOne<User> GetUser(int id)
{
    var user = _repository.Find(id);
    if (user is null) return new UserNotFoundError();
    return user;
}

No exceptions for expected failures. Either you get a User, or you get an AppError.

3. Resolve in your controllers

// Automatic mapping — success becomes 200 OK, error uses its own StatusCode
return result.Resolve();
 
// Custom success response — error still maps automatically
return result.Resolve(user => Created($"/users/{user.Id}", user));

4. Handle unexpected exceptions globally

Register the middleware once in Program.cs and all unhandled exceptions are caught and returned as a consistent JSON response — no stack traces leaking to the client.

app.UseCatchAll();

The response body follows this structure:

{
  "name": "An unexpected error occurred",
  "detail": "Object reference not set to an instance of an object",
  "path": "/users/42"
}

Options

app.UseCatchAll(options =>
{
    options.IncludeStackTrace = true;
    options.IncludeExceptionType = true;
    options.OnUnhandledException = ex => logger.LogError(ex, "Unhandled exception");
});

Why CatchAll?

Contributing

Contributions are welcome! Feel free to open an issue for bugs or suggestions, or submit a pull request.

Please keep PRs focused — one feature or fix per PR makes reviews much easier.

License

MIT © Bruno Ferreira