Question

我正在创建一个在我们的存储中读取自定义文件的函数。 function.json与此类似：

{
  "disabled": false,
  "bindings": [
    {
      "authLevel": "anonymous",
      "type": "httpTrigger",
      "direction": "in",
      "name": "req",
      "route": "resource/{code}",
      "methods": [
        "get"
      ]
    },
    {
      "type": "blob",
      "name": "item",
      "path": "data/20171003/{code}.json",
      "connection": "blog_STORAGE",
      "direction": "in"
    },
    {
      "type": "http",
      "direction": "out",
      "name": "res"
    }
  ]
}

在postman中，如果我输入现有文件，它将正确调用该函数。如果文件不存在，另一方面，azure运行时将抛出错误：

{       “id”：“4ef77dcd-f8ed-4327-9447-969da6b328a9”，       “requestId”：“0a9874dd-6a7b-4717-ae9f-c3c1e3bb16c8”，       “statusCode”：500，       “errorCode”：0，       “message”：“执行函数时出现异常：Functions.func_ativos - ＆gt;Valornãopodeser nulo。\ r \ nNome do   parâmetro：stream“，       “errorDetails”：“Microsoft.Azure.WebJobs.Host.FunctionInvocationException：Exception   执行函数时：Functions.func_ativos ---＆gt;   System.ArgumentNullException：Valornãopodeser nulo。\ r \ nNome do   parâmetro：stream \ r \ n在System.IO.StreamReader..ctor（Stream   流，编码编码，布尔值   detectEncodingFromByteOrderMarks，Int32 bufferSize，Boolean   leaveOpen）\ r \ n在System.IO.StreamReader..ctor（Stream stream）\ r \ n
  在   Microsoft.Azure.WebJobs.Script.Binding.FunctionBinding.ConvertStreamToValue（流   stream，DataType dataType，Object＆amp;转换）\ r \ n在异步   Microsoft.Azure.WebJobs.Script.Binding.FunctionBinding.BindStreamAsync（BindingContext中   上下文，FileAccess访问）\ r \ n在async   Microsoft.Azure.WebJobs.Script.Binding.ExtensionBinding.BindAsync（BindingContext中   上下文\ r \ n在异步   Microsoft.Azure.WebJobs.Script.Description.NodeFunctionInvoker.ProcessInputBindingsAsync（粘结剂   binder，Dictionary 2 executionContext,Dictionary 2 bindingData）\ r \ n
  在async   Microsoft.Azure.WebJobs.Script.Description.NodeFunctionInvoker.InvokeCore（对象[]   参数，FunctionInvocationContext上下文）\ r \ n在async中   Microsoft.Azure.WebJobs.Script.Description.FunctionInvokerBase.Invoke（对象[]   参数）\ r \ n在异步   Microsoft.Azure.WebJobs.Host.Executors.VoidTaskMethodInvoker 2.InvokeAsync[TReflected,TReturnType](TReflected instance,Object[] arguments)\r\n at async Microsoft.Azure.WebJobs.Host.Executors.FunctionInvoker 2.InvokeAsync [TReflected，TReturnValue]（对象[]   参数）\ r \ n在异步   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.InvokeAsync（IFunctionInvoker   invoker，ParameterHelper parameterHelper，CancellationTokenSource   timeoutTokenSource，CancellationTokenSource   functionCancellationTokenSource，Boolean throwOnTimeout，TimeSpan   timerInterval，IFunctionInstance实例）\ r \ n在async中   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithWatchersAsync（IFunctionInstance   实例，ParameterHelper parameterHelper，TraceWriter   traceWriter，ILogger logger，CancellationTokenSource   functionCancellationTokenSource）\ r \ n在异步   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync（??）\ r \ n   在async   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync（??）   \ r \ n内部异常结束\ r \ n at   System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw（个）\ r \ n
  在async   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ExecuteWithLoggingAsync（??）\ r \ n   在async   Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.TryExecuteAsync（IFunctionInstance   functionInstance，CancellationToken cancellationToken）\ r \ n at   Microsoft.Azure.WebJobs.Host.Executors.ExceptionDispatchInfoDelayedException.Throw（个）\ r \ n   异步Microsoft.Azure.WebJobs.JobHost.CallAsync（??）\ r \ n atync   Microsoft.Azure.WebJobs.Script.ScriptHost.CallAsync（字符串   方法，字典2 arguments,CancellationToken cancellationToken)\r\n at async Microsoft.Azure.WebJobs.Script.WebHost.WebScriptHostManager.HandleRequestAsync(FunctionDescriptor function,HttpRequestMessage request,CancellationToken cancellationToken)\r\n at async Microsoft.Azure.WebJobs.Script.WebHost.Controllers.FunctionsController.ProcessRequestAsync(HttpRequestMessage request,FunctionDescriptor function,CancellationToken cancellationToken)\r\n at async Microsoft.Azure.WebJobs.Script.WebHost.Controllers.FunctionsController.<>c__DisplayClass3_0.<ExecuteAsync>b__0(??)\r\n at async Microsoft.Azure.WebJobs.Extensions.Http.HttpRequestManager.ProcessRequestAsync(HttpRequestMessage request,Func 3 processRequestHandler，CancellationToken   cancelToken）\ r \ n在异步   Microsoft.Azure.WebJobs.Script.WebHost.Controllers.FunctionsController.ExecuteAsync（HttpControllerContext   controllerContext，CancellationToken cancellationToken）\ r \ n在异步   System.Web.Http.Dispatcher.HttpControllerDispatcher.SendAsync（HttpRequestMessage   请求，取消语音取消语句）\ r \ n在异步   System.Web.Http.Dispatcher.HttpControllerDispatcher.SendAsync（HttpRequestMessage   请求，取消语音取消语句）\ r \ n在异步   Microsoft.Azure.WebJobs.Script.WebHost.Handlers.SystemTraceHandler.SendAsync（HttpRequestMessage   请求，取消语音取消语句）\ r \ n在异步   Microsoft.Azure.WebJobs.Script.WebHost.Handlers.WebScriptHostHandler.SendAsync（HttpRequestMessage   请求，取消语音取消语句）\ r \ n在异步   System.Web.Http.HttpServer.SendAsync（HttpRequestMessage   请求，取消语音取消语句）“}

我想在找不到文件时发送404状态代码，而不是像那样丑陋的堆栈（和错误500）。我应该遵循的最佳方法是什么？

== update

请注意 FunctionInvocationException 在调用我的函数之前发生。在 Azure Functions Runtime 中似乎是一个错误，我不知道它是错误还是预期。

Answer 1

我们也可以在Azure功能App中捕获异常。在您的情况下，您可以捕获异常并返回http状态代码HttpStatusCode.NotFound

 public static HttpResponseMessage Run([HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)]HttpRequestMessage req, TraceWriter log)
        {
            log.Info("C# HTTP trigger function processed a request.");

            try
            {
                //Todo ：Add your own logic
            }
            catch (Exception ex)
            {
                return req.CreateResponse(HttpStatusCode.NotFound);
            }
            return req.CreateResponse(HttpStatusCode.OK);
        }

修改

正如您所说，它在调用函数之前发生，似乎是Azure功能集成SDK返回的。它可能是按设计的。我们也可以将我们的想法提交给azure function team。

如果我们想控制逻辑，我的工作是我们可以删除输入blob并自己实现自定义逻辑。我们可以从Microsoft Azure Storage SDK for Node.js获取示例代码。

找不到blob文件时的FunctionInvocationException

1 个答案: