无法解析参数'Microsoft.AspNetCore.Mvc.ApiExplorer.IApiDescriptionGroupCollectionProvider apiDescriptionsProvider

Question

我们用swagger探索api，有一次我们关掉了剃刀。

这导致了招摇的问题

原始错误：

An unhandled exception occurred while processing the request.
DependencyResolutionException: None of the constructors found with 'Autofac.Core.Activators.Reflection.DefaultConstructorFinder' 
  on type 'Swashbuckle.AspNetCore.SwaggerGen.SwaggerGenerator' can be invoked with the available services and parameters:
Cannot resolve parameter 'Microsoft.AspNetCore.Mvc.ApiExplorer.IApiDescriptionGroupCollectionProvider apiDescriptionsProvider' 
  of constructor 'Void .ctor(Microsoft.AspNetCore.Mvc.ApiExplorer.IApiDescriptionGroupCollectionProvider, Swashbuckle.AspNetCore.SwaggerGen.ISchemaRegistryFactory, Microsoft.Extensions.Options.IOptions`1[Swashbuckle.AspNetCore.SwaggerGen.SwaggerGeneratorOptions])'.
Cannot resolve parameter 'Microsoft.AspNetCore.Mvc.ApiExplorer.IApiDescriptionGroupCollectionProvider apiDescriptionsProvider' 
of constructor 'Void .ctor(Microsoft.AspNetCore.Mvc.ApiExplorer.IApiDescriptionGroupCollectionProvider, Swashbuckle.AspNetCore.SwaggerGen.ISchemaRegistryFactory, Swashbuckle.AspNetCore.SwaggerGen.SwaggerGeneratorOptions)'.
Autofac.Core.Activators.Reflection.ReflectionActivator.GetValidConstructorBindings(IComponentContext context, IEnumerable<Parameter> parameters)

Answer 1

问题是如何出现的：我们使用services.AddMvcCore而不是services.AddMvc

如何解决：添加ApiExplorer的注册

例如：

services.AddMvcCore()
    .AddJsonFormatters()
    .AddApiExplorer(); // this line is solution of problem