/// <summary>
/// Implements getting the stream without specifying a range.
/// </summary>
/// <param name="blob">The blob.</param>
/// <param name="attributes">The attributes.</param>
/// <param name="destStream">The destination stream.</param>
/// <param name="offset">The offset.</param>
/// <param name="length">The length.</param>
/// <param name="accessCondition">An object that represents the access conditions for the blob. If null, no condition is used.</param>
/// <param name="options">An object that specifies any additional options for the request.</param>
/// <returns>
/// A <see cref="RESTCommand{T}" /> that gets the stream.
/// </returns>
internal static RESTCommand <NullType> GetBlobImpl(ICloudBlob blob, BlobAttributes attributes, Stream destStream, long?offset, long?length, AccessCondition accessCondition, BlobRequestOptions options)
{
string lockedETag = null;
AccessCondition lockedAccessCondition = null;
bool isRangeGet = offset.HasValue;
bool arePropertiesPopulated = false;
string storedMD5 = null;
long startingOffset = offset.HasValue ? offset.Value : 0;
long?startingLength = length;
RESTCommand <NullType> getCmd = new RESTCommand <NullType>(blob.ServiceClient.Credentials, attributes.Uri);
getCmd.ApplyRequestOptions(options);
getCmd.RetrieveResponseStream = true;
getCmd.DestinationStream = destStream;
getCmd.CalculateMd5ForResponseStream = !options.DisableContentMD5Validation.Value;
getCmd.BuildRequestDelegate = (uri, builder, serverTimeout, ctx) =>
BlobHttpWebRequestFactory.Get(uri, serverTimeout, attributes.SnapshotTime, offset, length, options.UseTransactionalMD5.Value, accessCondition, ctx);
getCmd.SignRequest = blob.ServiceClient.AuthenticationHandler.SignRequest;
getCmd.RecoveryAction = (cmd, ex, ctx) =>
{
if ((lockedAccessCondition == null) && !string.IsNullOrEmpty(lockedETag))
{
lockedAccessCondition = AccessCondition.GenerateIfMatchCondition(lockedETag);
if (accessCondition != null)
{
lockedAccessCondition.LeaseId = accessCondition.LeaseId;
}
}
if (cmd.StreamCopyState != null)
{
offset = startingOffset + cmd.StreamCopyState.Length;
if (startingLength.HasValue)
{
length = startingLength.Value - cmd.StreamCopyState.Length;
}
}
getCmd.BuildRequestDelegate = (uri, builder, serverTimeout, context) =>
BlobHttpWebRequestFactory.Get(uri, serverTimeout, attributes.SnapshotTime, offset, length, options.UseTransactionalMD5.Value && !arePropertiesPopulated, lockedAccessCondition ?? accessCondition, context);
};
getCmd.PreProcessResponse = (cmd, resp, ex, ctx) =>
{
HttpResponseParsers.ProcessExpectedStatusCodeNoException(offset.HasValue ? HttpStatusCode.PartialContent : HttpStatusCode.OK, resp, NullType.Value, cmd, ex, ctx);
if (!arePropertiesPopulated)
{
CloudBlobSharedImpl.UpdateAfterFetchAttributes(attributes, resp, isRangeGet);
storedMD5 = resp.Headers[HttpResponseHeader.ContentMd5];
if (!options.DisableContentMD5Validation.Value &&
options.UseTransactionalMD5.Value &&
string.IsNullOrEmpty(storedMD5))
{
throw new StorageException(
cmd.CurrentResult,
SR.MD5NotPresentError,
null)
{
IsRetryable = false
};
}
lockedETag = attributes.Properties.ETag;
arePropertiesPopulated = true;
}
return(NullType.Value);
};
getCmd.PostProcessResponse = (cmd, resp, ex, ctx) =>
{
long validateLength = startingLength.HasValue ? startingLength.Value : (attributes.Properties.Length - startingOffset);
HttpResponseParsers.ValidateResponseStreamMd5AndLength(validateLength, storedMD5, cmd, cmd.StreamCopyState);
return(NullType.Value);
};
return(getCmd);
}
/// <summary>
/// Implements getting the blob.
/// </summary>
/// <param name="blob">The blob object that is calling this method.</param>
/// <param name="attributes">The blob's attributes.</param>
/// <param name="destStream">The target stream.</param>
/// <param name="offset">The offset at which to begin downloading the blob, in bytes.</param>
/// <param name="length">The length of the data to download from the blob, in bytes.</param>
/// <param name="accessCondition">An object that represents the access conditions for the blob. If null, no condition is used.</param>
/// <param name="options">An object that specifies additional options for the request.</param>
/// <returns>A <see cref="SynchronousTask"/> that gets the stream.</returns>
internal static RESTCommand <NullType> GetBlobImpl(ICloudBlob blob, BlobAttributes attributes, Stream destStream, long?offset, long?length, AccessCondition accessCondition, BlobRequestOptions options)
{
string lockedETag = null;
AccessCondition lockedAccessCondition = null;
bool isRangeGet = offset.HasValue;
bool arePropertiesPopulated = false;
string storedMD5 = null;
long startingOffset = offset.HasValue ? offset.Value : 0;
long?startingLength = length;
long?validateLength = null;
RESTCommand <NullType> getCmd = new RESTCommand <NullType>(blob.ServiceClient.Credentials, attributes.StorageUri);
options.ApplyToStorageCommand(getCmd);
getCmd.CommandLocationMode = CommandLocationMode.PrimaryOrSecondary;
getCmd.RetrieveResponseStream = true;
getCmd.DestinationStream = destStream;
getCmd.CalculateMd5ForResponseStream = !options.DisableContentMD5Validation.Value;
getCmd.Handler = blob.ServiceClient.AuthenticationHandler;
getCmd.BuildClient = HttpClientFactory.BuildHttpClient;
getCmd.BuildRequest = (cmd, uri, builder, cnt, serverTimeout, ctx) => BlobHttpRequestMessageFactory.Get(uri, serverTimeout, attributes.SnapshotTime, offset, length, options.UseTransactionalMD5.Value, accessCondition, cnt, ctx);
getCmd.RecoveryAction = (cmd, ex, ctx) =>
{
if ((lockedAccessCondition == null) && !string.IsNullOrEmpty(lockedETag))
{
lockedAccessCondition = AccessCondition.GenerateIfMatchCondition(lockedETag);
if (accessCondition != null)
{
lockedAccessCondition.LeaseId = accessCondition.LeaseId;
}
}
if (cmd.StreamCopyState != null)
{
offset = startingOffset + cmd.StreamCopyState.Length;
if (startingLength.HasValue)
{
length = startingLength.Value - cmd.StreamCopyState.Length;
}
}
getCmd.BuildRequest = (command, uri, builder, cnt, serverTimeout, context) => BlobHttpRequestMessageFactory.Get(uri, serverTimeout, attributes.SnapshotTime, offset, length, options.UseTransactionalMD5.Value && !arePropertiesPopulated, lockedAccessCondition ?? accessCondition, cnt, context);
};
getCmd.PreProcessResponse = (cmd, resp, ex, ctx) =>
{
HttpResponseParsers.ProcessExpectedStatusCodeNoException(offset.HasValue ? HttpStatusCode.PartialContent : HttpStatusCode.OK, resp, NullType.Value, cmd, ex);
if (!arePropertiesPopulated)
{
CloudBlobSharedImpl.UpdateAfterFetchAttributes(attributes, resp, isRangeGet);
if (resp.Content.Headers.ContentMD5 != null)
{
storedMD5 = Convert.ToBase64String(resp.Content.Headers.ContentMD5);
}
if (!options.DisableContentMD5Validation.Value &&
options.UseTransactionalMD5.Value &&
string.IsNullOrEmpty(storedMD5))
{
throw new StorageException(
cmd.CurrentResult,
SR.MD5NotPresentError,
null)
{
IsRetryable = false
};
}
// If the download fails and Get Blob needs to resume the download, going to the
// same storage location is important to prevent a possible ETag mismatch.
getCmd.CommandLocationMode = cmd.CurrentResult.TargetLocation == StorageLocation.Primary ? CommandLocationMode.PrimaryOnly : CommandLocationMode.SecondaryOnly;
lockedETag = attributes.Properties.ETag;
validateLength = resp.Content.Headers.ContentLength;
arePropertiesPopulated = true;
}
return(NullType.Value);
};
getCmd.PostProcessResponse = (cmd, resp, ctx) =>
{
HttpResponseParsers.ValidateResponseStreamMd5AndLength(validateLength, storedMD5, cmd);
return(Task.FromResult(NullType.Value));
};
return(getCmd);
}