在OperationFilter中检索API的响应内容类型

Question

例如，考虑一个带有 :

的 API

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen(o => o.OperationFilter<CustomFilter>());

var app = builder.Build();
app.UseSwagger();
app.UseSwaggerUI();
app.MapGet("/", () => { }).WithOpenApi();
app.Run();

此 API 可以返回内容类型为

application/json

和

application/xml

的响应。

我想创建一个自定义

OperationFilter

来生成具有 API 内容类型可能性的 OpenApi 响应 :

public class Foo { }

public class CustomFilter : IOperationFilter
{
    public void Apply(OpenApiOperation operation, OperationFilterContext context)
    {
        var schema = context.SchemaGenerator.GenerateSchema(typeof(Foo), context.SchemaRepository);
        operation.Responses.Clear();
        var response = new OpenApiResponse();
        var apiResponseTypes = new[] { "application/json", "application/xml" }; // <- How get this from API metadata? 
        foreach(string responseType in apiResponseTypes)
        {
            response.Content.Add(responseType, new OpenApiMediaType { Schema = schema });
        }
        operation.Responses.Add("200", response);
    }
}

如何检索OperationFilter中的API响应内容类型？

Answer 1

要在自定义

OperationFilter

中检索 API 响应内容类型，您可以从操作方法的属性访问

ProducesAttribute

。

public class CustomFilter : IOperationFilter
{
    public void Apply(OpenApiOperation operation, OperationFilterContext context)
    {
        var schema = context.SchemaGenerator.GenerateSchema(typeof(WeatherForecast), context.SchemaRepository);
        operation.Responses.Clear();

        var response = new OpenApiResponse();

        // Get the ProducesAttribute from the action method
        var producesAttribute = context.MethodInfo.GetCustomAttribute<ProducesAttribute>();

        if (producesAttribute != null)
        {
            foreach (var responseType in producesAttribute.ContentTypes)
            {
                response.Content.Add(responseType, new OpenApiMediaType { Schema = schema });
            }
        }

        operation.Responses.Add("200", response);
    }
}