byte[] BufferTip(long position, int count)
{
var buffer = new byte[count];
using (var s = _blob.OpenRead())
{
s.ReadAheadSize = count;
s.Seek(position, SeekOrigin.Begin);
s.Read(buffer, 0, count);
return(buffer);
}
}
// Get a page of a page blob.
// Return true on success, false if unable to create, throw exception on error.
public bool GetPage(string containerName, string blobName, int pageOffset, int pageSize, out string content)
{
content = null;
try
{
CloudBlobContainer container = BlobClient.GetContainerReference(containerName);
CloudPageBlob blob = container.GetPageBlobReference(blobName);
BlobStream stream = blob.OpenRead();
byte[] data = new byte[pageSize];
stream.Seek(pageOffset, SeekOrigin.Begin);
stream.Read(data, 0, pageSize);
content = new UTF8Encoding().GetString(data);
stream.Close();
return(true);
}
catch (StorageClientException ex)
{
if ((int)ex.StatusCode == 404)
{
return(false);
}
throw;
}
}
public override int Read(byte[] buffer, int offset, int count)
{
if (count % PageSize != 0)
{
throw new Exception("offset not page aligned");
}
if (count == 0)
{
return(0);
}
long len = Length;
if (Position + count > len) // Length will send HTTP request
{
return(0);
}
using (var _stream = _blob.OpenRead())
{
_stream.Seek(Position, SeekOrigin.Begin);
int readBytes = _stream.Read(buffer, offset, count);
_position += readBytes;
return(readBytes);
}
}
public static VhdFooter GetVhdFooter(this CloudPageBlob basePageBlob)
{
var vhdFileFactory = new VhdFileFactory();
using (var file = vhdFileFactory.Create(basePageBlob.OpenRead()))
{
return(file.Footer);
}
}
public PageBlobReadStream(CloudPageBlob blob)
{
_blob = blob;
if (!_blob.Exists())
{
throw new ArgumentException();
}
_reader = new BinaryReader(_blob.OpenRead());
}
static void Main(string[] args)
{
string uri = @"msds:nc?file=\\vienna.mslab.cs.msu.su\ClimateData\air.sig995.2007.nc&openMode=readOnly";
DataSet d = DataSet.Open(uri);
string blobUri = @"msds:ab?UseDevelopmentStorage=true&Container=testcontainer&Blob=testblob";
DataSet blobD = /*new AzureBlobDataSet(blobUri);*/ AzureBlobDataSet.ArrangeData(blobUri, d, new SerializableVariableSchema[0]);
AzureBlobDataSetUri azureUri = new AzureBlobDataSetUri(blobUri);
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(azureUri.ConnectionString);
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
// Retrieve a reference to a container
CloudBlobContainer container = blobClient.GetContainerReference(azureUri.Container);
CloudPageBlob blob = container.GetPageBlobReference(azureUri.Blob);
Int32 schemeSize;
using (BinaryReader br = new BinaryReader(blob.OpenRead()))
{
//schemeSize = br.ReadInt32();
UTF8Encoding utf8 = new UTF8Encoding();
byte[] buffer = new byte[8192];
br.BaseStream.Read(buffer, 0, 8192);
string sizeStr = utf8.GetString(buffer);
Console.WriteLine(sizeStr);
//schemeSize = Int32.Parse(sizeStr);
//br.BaseStream.Seek(512, SeekOrigin.Begin);
//DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(DataSetInfo));
//byte[] scheme = new byte[schemeSize];
//br.BaseStream.Read(scheme, 0, schemeSize);
//info = (DataSetInfo)serializer.ReadObject(new MemoryStream(scheme));
}
//foreach (var i in blobD.Variables) Console.WriteLine(i.Name);
Single[] a = (Single[])blobD["lat"].GetData();
blobD["lat"].PutData(a);
//foreach (var i in a) Console.WriteLine(i.ToString());
foreach (var i in blobD["lat"].Metadata)
{
Console.WriteLine(i.Key.ToString() + " = " + i.Value.ToString());
}
foreach (var i in blobD.Metadata)
{
Console.WriteLine(i.Key.ToString() + " = " + i.Value.ToString());
}
Console.ReadLine();
}
public byte[] ReadPage(long offset)
{
Require.OffsetMultiple("offset", offset, PageSize);
using (var stream = _blob.OpenRead()) {
var buffer = new byte[PageSize];
stream.Seek(offset, SeekOrigin.Begin);
stream.Read(buffer, 0, PageSize);
return(buffer);
}
}
public static void DownloadVHDFromCloud(CloudBlobClient blobStorage, string containerName, string blobName)
{
CloudBlobContainer container = blobStorage.GetContainerReference(containerName);
CloudPageBlob pageBlob = container.GetPageBlobReference(blobName);
// Get the length of the blob
pageBlob.FetchAttributes();
long vhdLength = pageBlob.Properties.Length;
long totalDownloaded = 0;
Console.WriteLine("Vhd size: " + Megabytes(vhdLength));
// Create a new local file to write into
FileStream fileStream = new FileStream(blobName, FileMode.Create, FileAccess.Write);
fileStream.SetLength(128 * OneMegabyteAsBytes);
// Download the valid ranges of the blob, and write them to the file
IEnumerable <PageRange> pageRanges = pageBlob.GetPageRanges();
Stream blobStream = pageBlob.OpenRead();
foreach (PageRange range in pageRanges)
{
// EndOffset is inclusive... so need to add 1
int rangeSize = (int)(range.EndOffset + 1 - range.StartOffset);
// Chop range into 4MB chucks, if needed
for (int subOffset = 0; subOffset < rangeSize; subOffset += FourMegabyteAsBytes)
{
int subRangeSize = Math.Min(rangeSize - subOffset, FourMegabyteAsBytes);
blobStream.Seek(range.StartOffset + subOffset, SeekOrigin.Begin);
fileStream.Seek(range.StartOffset + subOffset, SeekOrigin.Begin);
Console.WriteLine("Range: ~" + Megabytes(range.StartOffset + subOffset)
+ " + " + PrintSize(subRangeSize));
byte[] buffer = new byte[subRangeSize];
blobStream.Read(buffer, 0, subRangeSize);
fileStream.Write(buffer, 0, subRangeSize);
totalDownloaded += subRangeSize;
if (totalDownloaded > 128 * OneMegabyteAsBytes)
{
break;
}
}
if (totalDownloaded > 128 * OneMegabyteAsBytes)
{
break;
}
}
Console.WriteLine("Downloaded " + Megabytes(totalDownloaded) + " of " + Megabytes(vhdLength));
}
public PageBlobAppendStream(CloudPageBlob blob)
{
_blob = blob;
if (blob == null)
{
throw new ArgumentNullException("blob");
}
_reader = new BinaryReader(_blob.OpenRead());
if (!blob.Exists())
{
_blob.Create(0);
_lastPageIndex = -1;
return;
}
_blobLength = _blob.Properties.Length;
_lastPageIndex = (_blobLength / PageSize) - 1;
}
protected virtual byte[] GetBytesFromBlob(long offset, int count)
{
byte[] buffer = new byte[count];
using (var stream = blob.OpenRead(new BlobRequestOptions()
{
Timeout = TimeSpan.FromMinutes(30.0)
}))
{
int curOffset = 0;
int curCount = count;
int temp = 0;
stream.Seek(offset, SeekOrigin.Begin);
do
{
temp = stream.Read(buffer, curOffset, count);
curOffset += temp;
curCount -= temp;
}while (curOffset < count);
}
return(buffer);
}
public AzureBlobDataSet(string uri)
{
AzureBlobDataSetUri azureUri = null;
if (DataSetUri.IsDataSetUri(uri))
{
azureUri = new AzureBlobDataSetUri(uri);
}
else
{
azureUri = AzureBlobDataSetUri.ToUri(uri);
}
this.uri = azureUri;
CloudStorageAccount storageAccount;// = CloudStorageAccount.Parse(azureUri.ConnectionString);
if (CloudStorageAccount.TryParse(azureUri.ConnectionString, out storageAccount))
{
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
// Retrieve a reference to a container
CloudBlobContainer container = blobClient.GetContainerReference(azureUri.Container);
blob = container.GetPageBlobReference(azureUri.Blob);
}
else
{
blob = new CloudPageBlob(@"http://" + azureUri.AccountName + @".blob.core.windows.net/" + azureUri.Container + @"/" + azureUri.Blob);
_anonymous = true;
}
SerializableDataSetSchema info;
Int32 schemeSize;
using (BinaryReader br = new BinaryReader(blob.OpenRead()))
{
int curOffset = 0;
int curCount = 512;
int temp = 0;
UTF8Encoding utf8 = new UTF8Encoding();
byte[] buffer = new byte[512];
do
{
temp = br.BaseStream.Read(buffer, curOffset, curCount);
curOffset += temp;
curCount -= temp;
} while (curOffset < 512);
string sizeStr = utf8.GetString(buffer);
schemeSize = Int32.Parse(sizeStr);
br.BaseStream.Seek(512, SeekOrigin.Begin);
DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(SerializableDataSetSchema));
byte[] scheme = new byte[schemeSize];
curOffset = 0;
curCount = schemeSize;
do
{
temp = br.BaseStream.Read(scheme, curOffset, curCount);
curOffset += temp;
curCount -= temp;
} while (curOffset < schemeSize);
info = (SerializableDataSetSchema)serializer.ReadObject(new MemoryStream(scheme));
}
bool savedAutoCommitState = IsAutocommitEnabled;
IsAutocommitEnabled = false;
Initialize(schemeSize, info);
Commit();
if (_anonymous)
{
this.SetCompleteReadOnly();
}
IsAutocommitEnabled = savedAutoCommitState;
_IsInitialized = true;
}
