Azure函数定时器触发器可以迭代容器或目录中的所有blobs吗？

Question

是否可以使用定期触发的函数（计时器触发器）循环访问 Azure 存储容器中的所有 Blob 并对其进行操作。

路径： {容器名称}/{目录名称}/{文件名}

using System;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Host;
using Microsoft.Extensions.Logging;

namespace SampleNamespace
{
    public static class SampleFunction
    {
        [FunctionName("SampleFunction")]
        public static void Run([TimerTrigger("0 */1 * * * *")]TimerInfo myTimer, ILogger log)
        {
            // How to iterate an operate on all blobs?
        }
    }
}

Answer 1

除了使用存储blob sdk(Ivan provide)之外，您可以使用blob绑定来获取容器客户端，然后执行列表操作。

您可以参考 blob 输入用法，可以找到它支持绑定 CloudBlobContainer 或 CloudBlobDirectory 类型。您可以参考下面的代码。

[FunctionName("Function1")]
public static async System.Threading.Tasks.Task RunAsync([TimerTrigger("0 */1 * * * *")]TimerInfo myTimer, ILogger log,
            [Blob("test",Connection = "AzureWebJobsStorage")]CloudBlobContainer container)
        {
            log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");
            var segment = await container.ListBlobsSegmentedAsync(null);
            var blobs = segment.Results;
            foreach (var blob in blobs) {

                log.LogInformation(blob.GetType().ToString(), blob.ToString());
            }
        }

如果将返回所有 blob 和 blob 目录，下面是我的测试结果，所以你需要判断返回类型是 CloudBlockBlob 还是 CloudBlobDirectory 然后执行列表操作。

Answer 2

您应该为azure函数安装此blob存储nuget包Microsoft.Azure.Storage.Blob。然后您可以使用ListBlos等sync方法代替async方法ListBlosSegmentedAsync。最后，您可以编写代码来操作这些blob。

代码如下：

using Microsoft.Azure.Storage;
using Microsoft.Azure.Storage.Blob;
using Microsoft.Azure.WebJobs;
using Microsoft.Extensions.Logging;
using System;

namespace FunctionApp7
{
    public static class Function1
    {
        [FunctionName("Function1")]
        public static void Run([TimerTrigger("0 */1 * * * *")]TimerInfo myTimer, ILogger log)
        {
            log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");

            log.LogInformation("the blobs list:");

            var connectionString = "DefaultEndpointsProtocol=https;AccountName=xx;AccountKey=xxxx;EndpointSuffix=core.windows.net";
            var containerName = "test4";
            var directoryName = "sub1";

            CloudStorageAccount storageAccount = CloudStorageAccount.Parse(connectionString);

            CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();

            CloudBlobContainer container = blobClient.GetContainerReference(containerName);

            //list blobs in a container
            var blobs = container.ListBlobs(useFlatBlobListing: true);

            foreach (IListBlobItem item in blobs)
            {
                if (item.GetType() == typeof(CloudBlockBlob))
                {
                    CloudBlockBlob blob = (CloudBlockBlob)item;
                    //other operation.
                }
            }

            //list blobs in a directory
            CloudBlobDirectory directory = container.GetDirectoryReference(directoryName);
            var blobs_2 = directory.ListBlobs(useFlatBlobListing: true);

            foreach(IListBlobItem item in blobs_2)
            {
                if (item.GetType() == typeof(CloudBlockBlob))
                {
                    CloudBlockBlob blob = (CloudBlockBlob)item;
                    //other operation.
                }
            }


        }
    }
}