c# - 带有 F# : System. InvalidOperationException 的 Swashbuckle:'无法找到所需的服务

Question

我在 C# 中创建了一个新的 ASP.NET Core Web 应用程序 并遵循 Get started with Swashbuckle and ASP.NET Core .效果很好。

我在 F# 中做了同样的事情并遇到了这个:

System.InvalidOperationException: 'Unable to 
find the required services. Please add all 
the required services by calling 
'IServiceCollection.AddMvc' inside the call 
to 'ConfigureServices(...)' in the 
application startup code.'

这是Startup.fs

namespace ASPNETSwagger

open Microsoft.AspNetCore.Builder
open Microsoft.AspNetCore.Hosting
open Microsoft.AspNetCore.Mvc
open Microsoft.Extensions.Configuration
open Microsoft.Extensions.DependencyInjection
open Swashbuckle.AspNetCore.Swagger

type Startup () =
    new (configuration: IConfiguration) as this =
        Startup() then
        this.Configuration <- configuration

    member _this.ConfigureServices(services: IServiceCollection) =
        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2) |> ignore
        services.AddSwaggerGen(fun c -> c.SwaggerDoc("v1", new Info(Title = "My API", Version = "v1")))

    member this.Configure(app: IApplicationBuilder, env: IHostingEnvironment) =
        app.UseSwagger() |> ignore
        app.UseSwaggerUI(fun c -> c.SwaggerEndpoint("swagger/v1/swagger.json", "My API V1")) |> ignore

        if (env.IsDevelopment()) then
            app.UseDeveloperExceptionPage() |> ignore
        else
            app.UseHsts() |> ignore

        app.UseHttpsRedirection() |> ignore
        app.UseMvc() |> ignore

    member val Configuration : IConfiguration = null with get, set

我该如何解决这个问题？

Answer 1

services.AddSwaggerGen(fun c -> c.SwaggerDoc("v1", new Info(Title = "My API", Version = "v1")))

是一个返回 IServiceCollection 的表达式。包含方法 ConfigureServices 需要返回 unit。因此，将 |> ignore 添加到该行的末尾或将 () 作为最后一行来修复签名。

此外，这一行

app.UseSwaggerUI(fun c -> c.SwaggerEndpoint("swagger/v1/swagger.json", "My API V1")) |> ignore

需要

app.UseSwaggerUI(fun c -> c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1")) |> ignore

缺少前导 /。