Options Pattern in .NET Core

This solution demos one of the usages of the Options Pattern in .NET Core.

Medium Article: Options Patter in .NET Core

When registering dependencies in the ConfigureServices method, you must have seen a pattern likes the following

services.AddDbContext<T>(options => options.**)

services.AddSwaggerGen(c => {
    c.SwaggerDoc(**);
})

This pattern is actually an extension method on top of IServiceCollection, and the naming convention of this type of extension method is AddSomeService(this IServiceCollection services, Action<SomeOptions> action). The action is a Lambda function, which can be used to provide extra parameters to the service.

In this blog post, we will create a similar service that can be registered by calling the services.AddMyService(Action<MyServiceOptions> action) method. We will pass options to MyService so that this service can be more flexible with extra parameters.

Intro to Options pattern in ASP.NET Core

Microsoft Doc

The options pattern uses classes to represent groups of related settings. When configuration settings are isolated by scenario into separate classes, the app adheres to two important software engineering principles:

• The Interface Segregation Principle (ISP) or Encapsulation – Scenarios (classes) that depend on configuration settings depend only on the configuration settings that they use.
• Separation of Concerns – Settings for different parts of the app aren't dependent or coupled to one another.

How to Create an Option Object in Tests

Options.Create(new MyServiceOptions
                {
                    Option1 = "say hello",
                    Option2 = true
                }
            )

License

Feel free to use the code in this repository as it is under MIT license.