使用 F# 的 Swashbuckle：System.InvalidOperationException：'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 Application 并遵循了 Get started with Swashbuckle and ASP.NET Core。效果很好。

我在 F# 和运行中做了同样的事情：

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 return 一个 IServiceCollection 的表达式。包含方法 ConfigureServices 需要 return unit。因此，在该行的末尾添加 |> ignore 或在最后一行添加 () 可以修复签名。

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 /。

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

Swashbuckle with F#: System.InvalidOperationException: 'Unable to find the required services

c#

f#

swashbuckle

asp.net-core