事件网格触发函数在函数成功运行后是否继续触发？

问题描述

我有一个由事件网格事件触发的Azure函数。仅当将Blob上传到存储帐户时，才会创建事件网格事件。

此功能现在已部署并运行良好，尽管由于某种原因，即使该功能已成功处理，该功能也会不断被同一事件触发？

示例：

• 昨天有8个成功的测试；都好：

  

• 今天我查看了日志，该功能继续执行！

• 错误：“斑点不存在”

• 昨天我在最后一次测试后删除了Blob。为什么事件网格仍在触发？

  

代码段：

def main(event: func.EventGridEvent):

        result = json.dumps({
            'id' : event.id,'data' : event.get_json(),'topic' : event.topic,'subject' : event.subject,'event_type' : event.event_type
        })

        logging.info('EventGrid trigger processing an event: %s',result)

        credential = DefaultAzureCredential()

        download_start_time = datetime.datetime.now()
        logging.info(f'######## Starting downloading blob from storage at ' + str(download_start_time) + ' ########')

        # =============================
        # Download blob from storage container:
        # =============================

        blob_client = BlobClient.from_blob_url(event.get_json()["url"],credential)
        blob_data = blob_client.download_blob().readall()
        blob_byte_stream = io.BytesIO(blob_data)

编辑1：这仍在发生，这次有所不同。

• 现在，成功传递消息并运行函数后，EventGrid会继续触发

我该如何调试？

解决方法

我终于弄清楚问题出在哪里……在使用Azure Storage Explorer测试Blob上传时，使用BlobClient.from_blob_url方法可以很好地工作。但是，当使用Azure Data Factory时，将使用其他API，并且EventGrid消息中的data.url属性不是实际的Blob URL（包含dfs而不是blob）。

奇怪的是，在我将此问题提交给支持团队后不久，一个新的blobUrl属性被添加到EventGrid data对象中。

在我的代码中，我只是将“ url”更改为“ blobUrl”，该方法成功了。 （我还改进了Python代码的错误处理，以适应将来出现的此类错误。）

Documented EventGrid消息（截至2020年12月10日）：

• 没有blobUrl属性

[{
  "topic": "/subscriptions/{subscription-id}/resourceGroups/Storage/providers/Microsoft.Storage/storageAccounts/my-storage-account","subject": "/blobServices/default/containers/my-file-system/blobs/new-file.txt","eventType": "Microsoft.Storage.BlobCreated","eventTime": "2017-06-26T18:41:00.9584103Z","id": "831e1650-001e-001b-66ab-eeb76e069631","data": {
    "api": "CreateFile","clientRequestId": "6d79dbfb-0e37-4fc4-981f-442c9ca65760","requestId": "831e1650-001e-001b-66ab-eeb76e000000","eTag": "\"0x8D4BCC2E4835CD0\"","contentType": "text/plain","contentLength": 0,"contentOffset": 0,"blobType": "BlockBlob","url": "https://my-storage-account.dfs.core.windows.net/my-file-system/new-file.txt","sequencer": "00000000000004420000000000028963","storageDiagnostics": {
    "batchId": "b68529f3-68cd-4744-baa4-3c0498ec19f0"
    }
  },"dataVersion": "2","metadataVersion": "1"
}]

实际出现的EventGrid消息：

• 通知blobUrl已添加到架构中

{
    "id": "long-string","data": {
        "api": "CreateFile","requestId": "long-string","eTag": "0x8D89B4FF7150079","contentType": "application/octet-stream","blobProperties": [{
            "acl": [{
                "access": "u::rw,u:long-string:rwx,g::rx,g:long-string:rx,m::rw,o::","permission": "0660","owner": "long-string","group": "$superuser"
            }]
        }],"blobUrl": "https://myfunction.blob.core.windows.net/container/20201208/730420201208080239.csv","url": "https://myfunction.dfs.core.windows.net/container/20201208/730420201208080239.csv","sequencer": "0000000000000000000000000000692c00000000000e1a99","identity": "long-string","storageDiagnostics": {
            "batchId": "long-string"
        }
    },"topic": "/subscriptions/long-string/resourceGroups/myResourceGroup/providers/Microsoft.Storage/storageAccounts/storageAccount","subject": "/blobServices/default/containers/container/blobs/20201208/730420201208080239.csv","event_type": "Microsoft.Storage.BlobCreated"
}

此处的另一项警告...请注意以上消息中的Content-Length

• CreateFile API不是实际消息，它表明已创建了Blob。
• FlushWithClose API是

文档中对此有一个注释。因此，我还必须设置一个EventGrid高级过滤器，该过滤器仅在生成FlushWithClose个事件时才触发（！）