Azure 云存储 SDK UploadFromStreamAsync 不起作用

Question

I am trying to upload files to Azure blob storage in .Net Core 2.1. Below is my code.

IFormFileCollection files = formCollection.Files;

foreach (var file in files)
{
    if (file.Length > 0)
    {
        _azureCloudStorage.UploadContent(cloudBlobContainer, file.OpenReadStream(), file.FileName);
    }
}

UploadContent implementation-

public async void UploadContent(CloudBlobContainer containerReference, Stream contentStream, string blobName)
{
    try
    {
        using (contentStream)
        {
            var blockBlobRef = containerReference.GetBlockBlobReference(blobName);
            //await containerReference.SetPermissionsAsync(new BlobContainerPermissions
            //{
            //    PublicAccess = BlobContainerPublicAccessType.Blob
            //});
            await blockBlobRef.UploadFromStreamAsync(contentStream);
        }
    }
    catch(Exception ex)
    {
        //Error here
    }
}

The code executes with below error-

{System.ObjectDisposedException: Cannot access a closed file. at System.IO.FileStream.get_Position() at Microsoft.AspNetCore.WebUtilities.FileBufferingReadStream.get_Position() at Microsoft.AspNetCore.Http.Internal.ReferenceReadStream.VerifyPosition() at Microsoft.AspNetCore.Http.Internal.ReferenceReadStream.ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken) at Microsoft.WindowsAzure.Storage.Core.Util.StreamExtensions.WriteToAsync[T](Stream stream, Stream toStream, IBufferManager bufferManager, Nullable 1 copyLength, Nullable 1 maxLength, Boolean calculateMd5, ExecutionState 1 executionState, StreamDescriptor streamCopyState, CancellationToken token) in C:\\Program Files (x86)\\Jenkins\\workspace\\release_dotnet_master\\Lib\\Common\\Core\\Util\\StreamExtensions.cs:line 301 at Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob.UploadFromStreamAsyncHelper(Stream source, Nullable 1 length, AccessCondition accessCondition, BlobRequestOptions options, OperationContext operationContext, IProgress 1 progressHandler, CancellationToken cancellationToken) in C:\\Program Files (x86)\\Jenkins\\workspace\\release_dotnet_master\\Lib\\WindowsRuntime\\Blob\\CloudBlockBlob.cs:line 352 at Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob.UploadFromStreamAsyncHelper(Stream source, Nullable 1 progressHandler, CancellationToken cancellationToken) in C:\\Program Files (x86)\\Jenkins\\workspace\\release_dotnet_master\\Lib\\WindowsRuntime\\Blob\\CloudBlockBlob.cs:line 352 at Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob.UploadFromStreamAsyncHelper(Stream source, Nullable 1 length, AccessCondition accessCondition, BlobRequestOptions options, OperationContext operationContext, CancellationToken cancellationToken) in C:\\Program Files (x86)\\Jenkins\\workspace\\release_dotnet_master\\Lib\\WindowsRuntime\\Blob\\CloudBlockBlob.cs:line 290 at Common.AzureCloudStorage.UploadContent(CloudBlobContainer containerReference, Stream contentStream, String blobName)

Alternate solution which worked for me: adding to azure blob storage with stream

Any help with this please? Please let me know if I can provide more details.

Answer 1

My solution was to wait until the task had completed before continuing, eg

    private async void SaveAsync(IFormFile file)
    {
        CloudBlockBlob blob = this.blobContainer.GetBlockBlobReference(file.FileName);
        var task = blob.UploadFromStreamAsync(file.OpenReadStream(), file.Length);

        while (task.IsCompleted == false) {
            Thread.Sleep(1000);
        }

    }

Maybe passing in the length helped as well?

Answer 2

My solution was to include the file length and set the position = 0.

MemoryStream outStr = new MemoryStream();
CloudBlockBlob myBlob = container.GetBlockBlobReference(name);
outStr.Position = 0;
await myBlob.UploadFromStreamAsync(outStr, outStr.Length);

Answer 3

Same problem, few years later (WindowsAzure.Storage version 3.0.3.0, targetFramework net45).
Synchonous UploadFromStream works, UploadFromStreamAsync does not. I would vote up to suspect Azure SDK does'nt hone async versions, rather than sdk usage deficiency. And, I am also a fairly experienced developer - too experienced to stumble now and then over a Microsoft feature which is declared, but doesn't work when scrutinized closer.
The same here for other async methods (eg SetPropertiesAsync ). I've been debugging my method (below), and was just losing the breakpoint after every * Async method - that's how I've figured this out. And out of curiousity changed the UploadFromStreamAsync => UploadFromStream , and then SetPropertiesAsync to just SetProperties .

    public async Task StoreItem(string filename, MemoryStream content, string contentType, ICloudBlob cloudBlob)
{
    cloudBlob.UploadFromStream(content); //this line works
    //await cloudBlob.UploadFromStreamAsync(content); //doesn't work
    cloudBlob.Properties.ContentType = contentType;
    cloudBlob.SetProperties();
    //await cloudBlob.SetPropertiesAsync(); //doesn't work either
}

Answer 4

Setting the position to 0 and passing stream length to UploadFromStreamAsync() solved my issue (file was not getting uploaded, even if the container existed already).

using (var stream = file.OpenReadStream())
{
    var fileBlob = container.GetBlockBlobReference(fileName);
    stream.Position = 0;
    fileBlob.UploadFromStreamAsync(stream, stream.Length);
}

Answer 5

I have tested your method UploadContent , it worked fine.

I guess your problem may be the file collection you got.

Here is my code for your reference:

using ConsoleAppCore.DAL;
using Microsoft.Azure.Storage;
using Microsoft.Azure.Storage.Blob;
using System;
using System.IO;

namespace ConsoleAppCore
{
    class Program
    {
        static void Main(string[] args)
        {
            Run();
            Console.WriteLine("Success");
            Console.ReadLine();
        }

        public static void Run()
        {
            CloudStorageAccount storageAccount = CloudStorageAccount.Parse("DefaultEndpointsProtocol=https;AccountName=xxxxx;AccountKey=O7xB6ebGq8e86XQSy2vkvSi/x/exxxxxxxxxxkly1DsQPYY5dF2JrAVHtBozbJo29ZrrGJA==;BlobEndpoint=https://xxxx.blob.core.windows.net/;QueueEndpoint=https://xxxx.queue.core.windows.net/;TableEndpoint=https://xxxx.table.core.windows.net/;FileEndpoint=https://xxxx.file.core.windows.net/;");

            CloudBlobClient cloudBlobClient = storageAccount.CreateCloudBlobClient();
            CloudBlobContainer container = cloudBlobClient.GetContainerReference("containertest");

            container.CreateIfNotExists();
            DirectoryInfo dir = new DirectoryInfo("E://Test");

            foreach (FileInfo file in dir.GetFiles())
            {

                BlobStorage.UploadContent(container, file.OpenRead(), file.Name);

            }
        }


    }
}

And the UploadContent method in my BlobStorage class:

using Microsoft.Azure.Storage.Blob;
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

namespace ConsoleAppCore.DAL
{
    public class BlobStorage
    {
        public static async void UploadContent(CloudBlobContainer containerReference, Stream contentStream, string blobName)
        {
            try
            {
                using (contentStream)
                {

                    var blockBlobRef = containerReference.GetBlockBlobReference(blobName);
                    //await containerReference.SetPermissionsAsync(new BlobContainerPermissions
                    //{
                    //    PublicAccess = BlobContainerPublicAccessType.Blob
                    //});
                    await blockBlobRef.UploadFromStreamAsync(contentStream);
                }
            }
            catch (Exception ex)
            {
                //Error here
            }
        }
    }
}