ASP.NET Core 8 Web API : how to add versioning?

Question

I'm creating a new ASP.NET Core 8 Web API. In my previous projects with .NET 6 or .NET 7, I can use:

services.AddApiVersioning(options =>
{
    options.DefaultApiVersion = new ApiVersion(1, 0);
    options.AssumeDefaultVersionWhenUnspecified = true;
    options.ReportApiVersions = true;
});

services.AddVersionedApiExplorer(options =>
{
    options.GroupNameFormat = "'v'VVV";
    options.SubstituteApiVersionInUrl = true;
});

Now, the package Microsoft.AspNetCore.Mvc.ApiExplorer is deprecated and I replaced it with the new one Asp.Versioning.Mvc.ApiExplorer but there is no extension for AddVersionedApiExplorer.

In the configuration for Swagger, I have the following code:

public class ConfigureSwaggerOptions : IConfigureNamedOptions<SwaggerGenOptions>
{
    private readonly IApiVersionDescriptionProvider _provider;

    public ConfigureSwaggerOptions(IApiVersionDescriptionProvider provider)
    {
        _provider = provider;
    }

    public void Configure(SwaggerGenOptions options)
    {
        foreach (var description in _provider.ApiVersionDescriptions)
        {
            options.SwaggerDoc(
                description.GroupName,
                CreateVersionInfo(description));
        }
    }

    public void Configure(string name, SwaggerGenOptions options)
    {
        Configure(options);
    }

    private static OpenApiInfo CreateVersionInfo(
        ApiVersionDescription description)
    {
        var info = new OpenApiInfo()
        {
            Title = "Test API",
            Version = description.ApiVersion.ToString(),
            Description = "This is a test API.",
        };

        if (description.IsDeprecated)
        {
            info.Description += " This API version has been deprecated.";
        }

        return info;
    }
}

When I run the application, I get this error

Unable to resolve service for type 'Asp.Versioning.ApiExplorer.IApiVersionDescriptionProvider' while attempting to activate 'Middletier.Api.Extensions.Configuration.ConfigureSwaggerOptions'.

How can I fix it?

Answer 1

AddApiVersioning works a bit different (it returns IApiVersioningBuilder). Install Asp.Versioning.Mvc.ApiExplorer which will allow to call AddApiExplorer on IApiVersioningBuilder returned by AddApiVersioning:

builder.Services.AddApiVersioning(options =>
    {
        options.DefaultApiVersion = new ApiVersion(1, 0);
        options.AssumeDefaultVersionWhenUnspecified = true;
        options.ReportApiVersions = true;
    })
    .AddApiExplorer(options =>
    {
        options.GroupNameFormat = "'v'VVV";
        options.SubstituteApiVersionInUrl = true;
    });

See the Quick Start, samples and this question - ApiVersion attribute not working in .NET 8