Owin 托管的 NancyFX 应用程序在发布到 IIS 后返回无法加载类型 Nancy.Hosting.Aspnet.NancyHttpRequestHandler

Question

虽然通过 VS Studio 附带的 IIS Express 在本地运行时它可以完美运行，但我的应用程序一旦部署到 IIS 8 就会卡住:

System.Web.HttpException: Could not load type 'Nancy.Hosting.Aspnet.NancyHttpRequestHandler'.

后端是 MS Owin，用 VB (.NET 4.5) 编写，注册了 3 个中间件:OAuth 服务器、JWT 承载身份验证和 Nancy。前端是AngularJS。正确的 DLL 包含在已发布的目录中。

IIS 8 安装并启用了 .NET 4.5。它正在集成模式下运行。

我不确定这是否与web.config中Nancy的配置或IIS的配置有关。相关来源如下:

启动.vb

Public Sub Configuration(app As IAppBuilder)

        Dim issuer As String = "http://obscured-domain"
        Dim audience As String = "obscured-audience-key"
        Dim secret As Byte() = Microsoft.Owin.Security.DataHandler.Encoder.TextEncodings.Base64Url.Decode("obscured-client-secret")

        'CORS Configuration
        app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll)
        app.UseOAuthAuthorizationServer(New OAuthAuthorizationServerOptions() With { _
                                    .AllowInsecureHttp = True, _
                                    .TokenEndpointPath = New PathString("/authenticate"), _
                                    .AccessTokenExpireTimeSpan = TimeSpan.FromHours(1), _
                                    .AccessTokenFormat = New JwtFormat(issuer, audience), _
                                    .Provider = New OAuthServerProvider()
                                })
        app.UseJwtBearerAuthentication(New JwtBearerAuthenticationOptions() With { _
                                       .AuthenticationMode = Microsoft.Owin.Security.AuthenticationMode.Active, _
                                       .AllowedAudiences = New String() {audience}, _
                                       .IssuerSecurityTokenProviders = New IIssuerSecurityTokenProvider() { _
                                           New SymmetricKeyIssuerSecurityTokenProvider(issuer, secret)
                                       }
                                   })
        'Content service
        Dim nOpts As New NancyOptions
        nOpts.PassThroughWhenStatusCodesAre(HttpStatusCode.NotFound, HttpStatusCode.InternalServerError)
        app.UseNancy(nOpts)
        'Handle IIS request pipeline staging
        app.UseStageMarker(PipelineStage.MapHandler)
    End Sub

Web.config

    <?xml version="1.0"?>
<configuration>
  <system.web>
    <customErrors mode="Off" />
    <compilation debug="true" targetFramework="4.5" />
    <httpRuntime targetFramework="4.5" />
    <httpHandlers>
      <add verb="*" type="Nancy.Hosting.Aspnet.NancyHttpRequestHandler" path="*" />
    </httpHandlers>
  </system.web>
  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true" />
    <validation validateIntegratedModeConfiguration="false" />
    <handlers>
      <add name="Nancy" verb="*" type="Nancy.Hosting.Aspnet.NancyHttpRequestHandler" path="*"/>
    </handlers>
  </system.webServer>
  <connectionStrings>
    <add name="FTConnStr" connectionString="obscured-connection-string" />
  </connectionStrings>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Microsoft.Owin" publicKeyToken="31bf3856ad364e35" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

Nancy 模块示例

Public Class KnowledgeBaseModule
Inherits NancyModule

    'Get page of article briefs via full-text search
    MyBase.Get("/api/articles/paged/{offset}/{numRows}") = _
    Function(parameters)
            Dim searchFields As FullTextFields = Me.Bind(Of FullTextFields)()
            Try
                Dim results As Dictionary(Of String, List(Of Dictionary(Of String, Object)))
                results = FullTextProvider.pagedSearch(searchFields.fields("SearchString"), CInt(parameters.offset), CInt(parameters.numRows))
                Return Response.AsJson(results)
            Catch ex As Exception
                'temp 500
                Return HttpStatusCode.InternalServerError
            End Try
        End Function

Private Class FullTextFields
    Public Property fields As Dictionary(Of String, String) = New Dictionary(Of String, String) From _
        {
            {"SearchString", String.Empty}
        }
End Class
End Class

Answer 1

由于您使用的是 OWIN，因此您需要使用 SystemWeb host不是南希的AspNet host 。您还需要从 web.config 中删除这两部分:

<httpHandlers>
  <add verb="*" type="Nancy.Hosting.Aspnet.NancyHttpRequestHandler" path="*" />
</httpHandlers>

<handlers>
  <add name="Nancy" verb="*" type="Nancy.Hosting.Aspnet.NancyHttpRequestHandler" path="*"/>
</handlers>

您的 bin 文件夹中可能有 nancy 主机的副本，这就是它在本地工作但在部署时不起作用的原因。