5.8 KiB
About
Microsoft.Extensions.Options
provides a strongly typed way of specifying and accessing settings using dependency injection and acts as a bridge between configuration, DI, and higher level libraries. This library is the glue for how an app developer uses DI to configure the behavior of a library like HttpClient Factory. This also enables user to get a strongly-typed view of their configuration.
Within this package, you'll find an options validation source generator that generates exceptionally efficient and optimized code for validating options.
Key Features
- Offer the IValidateOptions interface for the validation of options, along with several generic ValidateOptions classes that implement this interface.
- OptionsBuilder to configure options.
- Provide extension methods for service collections and options builder to register options and validate options.
- Supply a set of generic ConfigureNamedOptions classes that implement the IConfigureNamedOptions interface for configuring named options.
- Provide a source generator that generates validation code for options.
- Options caching, managing and monitoring.
How to Use
Options validation example
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddControllersWithViews();
// Load the configuration and validate it
builder.Services.AddOptions<MyConfigOptions>()
.Bind(builder.Configuration.GetSection(MyConfigOptions.MyConfig))
.ValidateDataAnnotations();
var app = builder.Build();
// Declare the option class to validate
public class MyConfigOptions
{
public const string MyConfig = "MyConfig";
[RegularExpression(@"^[a-zA-Z''-'\s]{1,40}$")]
public string Key1 { get; set; }
[Range(0, 1000,
ErrorMessage = "Value for {0} must be between {1} and {2}.")]
public int Key2 { get; set; }
public int Key3 { get; set; }
}
Using IValidateOptions to validate options
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddControllersWithViews();
// Configuration to validate
builder.Services.Configure<MyConfigOptions>(builder.Configuration.GetSection(
MyConfigOptions.MyConfig));
// OPtions validation through the DI container
builder.Services.AddSingleton<IValidateOptions
<MyConfigOptions>, MyConfigValidation>();
var app = builder.Build();
public class MyConfigValidation : IValidateOptions<MyConfigOptions>
{
public MyConfigOptions _config { get; private set; }
public MyConfigValidation(IConfiguration config)
{
_config = config.GetSection(MyConfigOptions.MyConfig)
.Get<MyConfigOptions>();
}
public ValidateOptionsResult Validate(string name, MyConfigOptions options)
{
string? vor = null;
var rx = new Regex(@"^[a-zA-Z''-'\s]{1,40}$");
var match = rx.Match(options.Key1!);
if (string.IsNullOrEmpty(match.Value))
{
vor = $"{options.Key1} doesn't match RegEx \n";
}
if ( options.Key2 < 0 || options.Key2 > 1000)
{
vor = $"{options.Key2} doesn't match Range 0 - 1000 \n";
}
if (_config.Key2 != default)
{
if(_config.Key3 <= _config.Key2)
{
vor += "Key3 must be > than Key2.";
}
}
if (vor != null)
{
return ValidateOptionsResult.Fail(vor);
}
return ValidateOptionsResult.Success;
}
}
Options Validation Source Generator Example
using System;
using System.ComponentModel.DataAnnotations;
using Microsoft.Extensions.Options;
public class MyConfigOptions
{
[RegularExpression(@"^[a-zA-Z''-'\s]{1,40}$")]
public string Key1 { get; set; }
[Range(0, 1000,
ErrorMessage = "Value for {0} must be between {1} and {2}.")]
public int Key2 { get; set; }
public int Key3 { get; set; }
}
[OptionsValidator]
public partial class MyConfigValidation : IValidateOptions<MyConfigOptions>
{
// Source generator will automatically provide the implementation of IValidateOptions
// Then you can add the validation to the DI Container using the following code:
//
// builder.Services.AddSingleton<IValidateOptions
// <MyConfigOptions>, MyConfigValidation>();
// builder.Services.AddOptions<MyConfigOptions>()
// .Bind(builder.Configuration.GetSection(MyConfigOptions.MyConfig))
// .ValidateDataAnnotations();
}
Main Types
The main types provided by this library are:
IOptions
,IOptionsFactory
, andIOptionsMonitor
IValidateOptions
andValidateOptions
OptionsBuilder
,OptionsFactory
,OptionsMonitor
, andOptionsManager
OptionsServiceCollectionExtensions
OptionsValidatorAttribute
Additional Documentation
Related Packages
Microsoft.Extensions.Logging Microsoft.Extensions.Configuration
Feedback & Contributing
Microsoft.Extensions.Options is released as open source under the MIT license. Bug reports and contributions are welcome at the GitHub repository.