HTTP Mapping Model and Defaults

This page explains how functional outcomes are translated to HTTP responses.

Mapping Flow

1. Your endpoint returns Result, Result<T>, or Maybe<T>.
2. Adapter extensions (ToHttpResult, ToActionResult) inspect the outcome.
3. Success and failure branches are converted to HTTP status codes and bodies.

Default Behavior

Success Cases

• Result.Success() maps to success status based on configured policy.
• Result<T>.Success(value) maps to 200 with a serialized body.
• Maybe<T>.Some(value) maps to 200 with a serialized body.

Failure Cases

Built-in mappings include:

• ValidationFailure -> 400
• NotFoundFailure -> 404
• UnauthorizedFailure -> 401
• UnauthenticatedFailure -> 403
• ConflictFailure -> 409
• ExceptionalFailure -> 500
• Unknown failure types -> 500

Why This Matters

Centralized mapping keeps HTTP concerns out of domain logic and ensures consistent behavior across endpoints.

Next

• Custom Mappers and Policy Composition
• Minimal API Patterns
• MVC and Controller Patterns