CloudBlob.OpenRead() is not reading all data

Question

With windows Azure Storage Client Library, CloudBlob.OpenRead() method reads only 4 mb of data. How can I read full stream using OpenRead method.

CloudBlob b         


        

Answer 1

I can't reproduce what you're seeing. Things seem to work as expected:

static void Main(string[] args)
{
    // I also tried a real cloud storage account. Same result.
    var container = CloudStorageAccount.DevelopmentStorageAccount.CreateCloudBlobClient().GetContainerReference("testcontainer");
    container.CreateIfNotExist();

    var blob = container.GetBlobReference("testblob.txt");

    blob.UploadText(new String('x', 5000000));

    var source = blob.OpenRead();

    int BUFFER_SIZE = 4000000;
    byte[] buffer = new byte[BUFFER_SIZE];
    int bytesRead;
    int bytesCopied = 0;
    do
    {
        bytesRead = source.Read(buffer, 0, BUFFER_SIZE);
        bytesCopied += bytesRead;
    } while (bytesRead > 0);

    Console.WriteLine(bytesCopied); // prints 5000000
}

EDIT:

I've also (in response to the edited question) now tried uploading the blob using OpenWrite, and the result is the same. (I get the full blob back.) I used this code in place of blob.UploadText(...):

using (var input = File.OpenRead(@"testblob.txt")) //5000000 bytes
using (var output = blob.OpenWrite())
{
    input.CopyTo(output);
}

The final WriteLine still prints 5000000.

EDIT 2:

This is getting a bit tiresome. Changing the BUFFER_SIZE to 65536 didn't change anything. The results still seem correct to me. Here's my full application for comparison:

static void Main(string[] args)
{
    // I also tried a real cloud storage account. Same result.
    var container = CloudStorageAccount.DevelopmentStorageAccount.CreateCloudBlobClient().GetContainerReference("testcontainer");
    container.CreateIfNotExist();

    var blob = container.GetBlobReference("testblob.txt");

    using (var input = File.OpenRead(@"testblob.txt")) //5000000 bytes
    using (var output = blob.OpenWrite())
    {
        input.CopyTo(output);
    }

    var source = blob.OpenRead();

    int BUFFER_SIZE = 65536;
    byte[] buffer = new byte[BUFFER_SIZE];
    int bytesRead;
    int bytesCopied = 0;
    do
    {
        bytesRead = source.Read(buffer, 0, BUFFER_SIZE);
        bytesCopied += bytesRead;
    } while (bytesRead > 0);

    Console.WriteLine(bytesCopied); // prints 5000000
}