BrutalHack.Bouncer 1.0.2

Bouncer

Bouncer provides lightweight runtime-only "contracts" for .Net applications. Focus lies on readability, extensibility and a high unit test coverage.

• Installing via NuGet
• Usage
  • with Bouncer
  • without Bouncer
• Custom Rules
  • Using Extension Methods
  • Using IsTrue
• Planned Features

Installing via NuGet

Install-Package BrutalHack.Bouncer

Usage

Import the Nuget Package and check constraints for your methods parameters in a few readable lines. When a constraint is violated, you receive a readable exception including stack trace.

with Bouncer

IBouncer Bouncer;

public CreateNewUser(string name, int age)
{
  Bouncer.IsNotNullOrEmpty(name);
  Bouncer.IsPositive(age)
  // Do Stuff
}

without Bouncer

public CreateNewUser(string name, int age)
{
  if (name == null)
  {
    throw new ArgumentNullException(nameof(name), "Must not be null.");
  }
  if (name.length == 0)
  {
    throw new ArgumentOutOfRangeException(nameof(name), "Must not be empty.");
  }
  if (age < 0)
  (
    throw new ArgumentOutOfRangeException(nameof(age), "Must be positive.");
  }
  
  // Do Stuff
}

Custom Rules

Using Extension Methods

Bouncer is easily extendible via C# Extension Methods. By extending IBouncer, your methods are available to all Bouncer instances retrieved via Bouncer.Instance or via Dependency Injection.

Example:

using System;
using System.Collections.Generic;

namespace BrutalHack.Bouncer
{
    public static class BouncerExtensions
    {
        /// <summary>
        /// Validates if a collection contains the given elements
        /// </summary>
        /// <param name="bouncer"></param>
        /// <param name="element"></param>
        /// <param name="collection"></param>
        /// <typeparam name="T">Generic Type of the given list</typeparam>
        /// <exception cref="ArgumentOutOfRangeException">thrown, when the list does not contain the given element.</exception>
        public static void Contains<T>(this IBouncer bouncer, T element, ICollection<T> collection)
        {
            if (!collection.Contains(element))
            {
                throw new ArgumentOutOfRangeException($"Collection {collection} must contain Element {element}.");
            }
        }
    }
}

Extension methods are used like normal methods on IBouncer:

var collection = new List<string>{"foo", "bar"};
_bouncer.Contains("not included", collection);

Using IsTrue

For rules, which are only needed once, you may also use IsTrue with a boolean expression.

We do not recommend this approach, as it can easily create duplicate code.

var collection = new List<string>{"foo", "bar"};
_bouncer.IsTrue(collection.Contains("not included"));

Planned Features

• More constraints
• Easily disable all constraints in production mode