Azure函数Python如何修复“blobTrigger :Microsoft.Azure.WebJobs.Extensions.Storage: Object未设置为对象实例”？

Question

使用更详细的调试输出更新下面

过去，我已经成功地使用本地dev主机运行Azure函数。

我最近还没能让blobTrigger正常工作。我已采取以下步骤：

func init NewWave
cd NewWave
func new # -> select httpTrigger called HttpTrigger in language python
func new # -> select blobTrigger called BlobTrigger in language python
func host start

host.json包含：

{
    "version": "2.0",
    "extensionBundle": {
        "id": "Microsoft.Azure.Functions.ExtensionBundle",
        "version": "[1.*, 2.0.0)"
    }
}

local.settings.json包含：

{
  "IsEncrypted": false,
  "Values": {
    "FUNCTIONS_WORKER_RUNTIME": "python",
    "AzureWebJobsStorage": "{AzureWebJobsStorage}"
  }
}

AzureWebJobsStorage是通过环境变量设置的连接字符串。

包含：

{
  "scriptFile": "__init__.py",
  "bindings": [
    {
      "name": "myblob",
      "type": "blobTrigger",
      "direction": "in",
      "path": "samples-workitems/{name}",
      "connection": ""
    }
  ]
}

__init__.py包含：

import logging

import azure.functions as func


def main(myblob: func.InputStream):
    logging.info(f"Python blob trigger function processed blob \n"
                 f"Name: {myblob.name}\n"
                 f"Blob Size: {myblob.length} bytes")

HttpTrigger加载，但BlobTrigger不加载。产出如下：

Azure Functions Core Tools (2.7.1373 Commit hash: cd9bfca26f9c7fe06ce245f5bf69bc6486a685dd)
Function Runtime Version: 2.0.12507.0
Warning: 'connection' property in '~/NewWave/BlobTrigger/function.json' is empty.
Skipping 'AzureWebJobsStorage' from local settings as it's already defined in current environment variables.
[...]
[6/24/19 12:45:28 PM] Starting JobHost
[...]
[6/24/19 12:45:28 PM] Generating 2 job function(s)
[6/24/19 12:45:28 PM] Found the following functions:
[6/24/19 12:45:28 PM] Host.Functions.HttpTrigger
[6/24/19 12:45:28 PM] Host.Functions.BlobTrigger
[6/24/19 12:45:28 PM]
[6/24/19 12:45:28 PM] Host initialized (280ms)

Http Functions:

    HttpTrigger: [GET,POST] http://localhost:7071/api/HttpTrigger

[6/24/19 12:45:28 PM] A host error has occurred
[6/24/19 12:45:28 PM] Microsoft.Azure.WebJobs.Extensions.Storage: Object reference not set to an instance of an object.
[6/24/19 12:45:28 PM] Stopping JobHost

是什么导致了这个错误，我如何解决它？

如果需要进一步的设置，日志等，请在下面的评论中提出建议，我会更新。

谢谢

操作系统: macOS高塞拉10.13.6

Python版本：

Python 3.6.8 Anaconda Inc.(缺省值，2018年12月29日，19:04:46) GCC 4.2.1兼容Clang 4.0.1 (标记/Release401/final)在达尔文类型“帮助”、“版权”、“信贷”或“许可”上获得更多信息。

pip冻结：

应用洞察力=0.1.0 azure-cognitiveservices-vision-customvision==1.0.0 azure-batch=4.1.3 azure==4.0.0 azure-azure==4.0.0=1.1.20 azure-cosmosdb-nspkg=2.0.2 azure-cosmosdb-table=1.0.5 azure-datalake-store==0.0.45 azure-azure==4.0.0 mgmt=1.2.0 azure-#en0#=1.0.0b8 azure-azure==4.0.0 batch=1.0.0b8 azure-keyvault==1.1.0 azure-loganalytics==0.azure-mgmt=4.0.0-mgmt=4.0.0.0.1 azure-mgmt-应用洞察力=0.1.1天青-mgmt-授权==0.50.0天青-mgmt-批处理=5.0.1天青-mgmt-batchai==2.0.0天-mgmt-帐单==0.2.0天青-mgmt-cdn==3.1.0 azure-mgmt-cdn=3.1.0 azure-mgmt-cognitiveservices=3.0.0 azure-mgmt-commerce=1.0.1 azure-mgmt-计算==4.6.2 azure-mgmt-计算=2.0.0 azure-mgmt-compute=1.4.1 azure-mgmt-.0.1=2.8.0mgerure=2.8.0mgmmt=4.4。0 azure-mgmt=0.4.1 azure-mgmt-datafactory=0.6.0 azure-mgmt-datalake-analytics==0.6.0 azure-mgmt-datalake-nspkg==3.0.1 azure-mgmt-datalake-store==0.5.0 azure-mgmt-datamigration=1.0.0 azure-mgmt-datamigration=1.0.0 azure-mgmt-devspaces==0.1.0 -mgmt-datalake==2.2.0.1.0 azure-mgmt=0.5.0 azure-machinelearningcompute=0.2.0 azure-mgmt=1.1.0 azure-mgmt=0.2.0 azure-mgmt-逻辑=3.0.0 azure-mgmt-mgmt-media=0.4.1 azure-mgmt managementpartner==0.1.0 azure-mgmt-managementpartner==0.1.0 azure-mgmt-mgmt-map=0.1.0 azure-mgmt-mgmt-media=1.1.0-mgmt-媒体=1.1mgmt-mgmt=0.5.2mgmt-mgmt=0.1.0mgmt-mgmt=0.1.0 mgmt-mgmt=0.1.0 mgmt=mgmt=0.1.0 mgmt=0.1.00 azure- mgmt-mgmt=2.7.0 azure-mgmt-通知集线器==2.1.0 azure-mgmt-nspkg=3.0.2 azure-mgmt==0.1.0 azure-mgmt-powerbiembedded==2.0.0 azure-mgmt-rdbms=1.8.0 azure-mgmt-recoveryservices=0.3.0天青-mgmt-recoveryservicesbackup=0.3.0 azure-mgmt-redis=5.0.0 azure-mgmt-中继=0.1.0-mgmt-预订=0.1.0mgmt-search=2.0.0 azure-mgmt-servicebus==0.5.3 azure-mgmt-servicefabric==0.2.0 azure- mgmt-signalr=0.1.1 azure-mgmt-sql=0.9.1 azure-mgmt-存储=2.0.0 azure-mgmt-订阅=0.2.0 azure-mgmt-流量管理器=0.50.0-mgmt-web=0.35.0-nspkg=3.0.2天青-servicebus=0.21.1-servicefabric=6.3.0.0蔚蓝-服务管理-遗留物=0.20.6=0.20.6-存储-存储=0.30.0-mgmt-web=0.35.0-nspkg=3.0.2天青-servicebus=0.21.1-servicefabric=6.3.0.0存储-blob==2.0.1 azure-存储-通用=2.0.0 azure-存储-文件=1.4.0天蓝色-存储-队列=1.4.0 msrestazure==0.6.0

更新

因此，我找到了一些更详细的日志文件(注意，我在macOS上)：

2019-06-24T11:14:42.213 [Error] A host error has occurred
System.NullReferenceException : Object reference not set to an instance of an object.
   at Microsoft.Azure.WebJobs.Host.Blobs.Listeners.CloudBlobClientComparer.GetHashCode(CloudBlobClient obj) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Extensions.Storage\Blobs\Listeners\CloudBlobClientComparer.cs : 34
   at System.Collections.Generic.Dictionary`2.TryInsert(TKey key,TValue value,InsertionBehavior behavior)
   at System.Collections.Generic.Dictionary`2.Add(TKey key,TValue value)
   at async Microsoft.Azure.WebJobs.Host.Blobs.Listeners.PollLogsStrategy.RegisterAsync(CloudBlobContainer container,ITriggerExecutor`1 triggerExecutor,CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Extensions.Storage\Blobs\Listeners\PollLogsStrategy.cs : 74
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Blobs.Listeners.ScanBlobScanLogHybridPollingStrategy.RegisterAsync(CloudBlobContainer container,ITriggerExecutor`1 triggerExecutor,CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Extensions.Storage\Blobs\Listeners\ScanBlobScanLogHybridPollingStrategy.cs : 61
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Blobs.Listeners.BlobListenerFactory.RegisterWithSharedBlobListenerAsync(String hostId,SharedBlobListener sharedBlobListener,CloudBlobClient blobClient,CloudQueue hostBlobTriggerQueue,IMessageEnqueuedWatcher messageEnqueuedWatcher,CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Extensions.Storage\Blobs\Listeners\BlobListenerFactory.cs : 155
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Blobs.Listeners.BlobListenerFactory.CreateAsync(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Extensions.Storage\Blobs\Listeners\BlobListenerFactory.cs : 93
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexer.ListenerFactory.CreateAsync(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexer.cs : 426
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Listeners.HostListenerFactory.CreateAsync(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Listeners\HostListenerFactory.cs : 62
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Listeners.ListenerFactoryListener.StartAsyncCore(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Listeners\ListenerFactoryListener.cs : 45
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Host.Listeners.ShutdownListener.StartAsync(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Listeners\ShutdownListener.cs : 29
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.JobHost.StartAsyncCore(CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\JobHost.cs : 101
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Script.ScriptHost.StartAsyncCore(CancellationToken cancellationToken) at C:\azure-webjobs-sdk-script\src\WebJobs.Script\Host\ScriptHost.cs : 241
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Extensions.Hosting.Internal.Host.StartAsync(CancellationToken cancellationToken)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at async Microsoft.Azure.WebJobs.Script.WebHost.WebJobsScriptHostService.StartHostAsync(CancellationToken cancellationToken,Int32 attemptCount,JobHostStartupMode startupMode) at C:\azure-webjobs-sdk-script\src\WebJobs.Script.WebHost\WebJobsScriptHostService.cs : 163

Answer 1

通过尝试和错误-和一个完全误导错误信息..。

答案只是将环境变量AzureWebJobsStorage设置为存储帐户的主访问键连接字符串，该字符串如下所示：

DefaultEndpointsProtocol=https;AccountName=<account name>;AccountKey=<account key>;EndpointSuffix=core.windows.net

而不是通过az storage account generate-sas创建的SAS连接字符串。

Answer 2

我建议您在"connection“中添加一个设置中为空的值。

{
    "scriptFile": "__init__.py",
    "disabled": false,
    "bindings": [
        {
            "name": "myblob",
            "type": "blobTrigger",
            "direction": "in",
            "path": "samples-workitems/{name}",
            "connection":"MyStorageAccountAppSetting"
        }
    ]
}

这是我的local.settings.json

{
  "IsEncrypted": false,
  "Values": {
    "AzureWebJobsStorage": "",
    "FUNCTIONS_WORKER_RUNTIME": "python",
    "mohitsa_STORAGE": ""
  }
}

希望能帮上忙。