/// <summary>
/// Read data entries and their corresponding eTags from the Azure table.
/// </summary>
/// <param name="filter">Filter string to use for querying the table and filtering the results.</param>
/// <returns>Enumeration of entries in the table which match the query condition.</returns>
public async Task <IEnumerable <Tuple <T, string> > > ReadTableEntriesAndEtagsAsync(string filter)
{
const string operation = "ReadTableEntriesAndEtags";
var startTime = DateTime.UtcNow;
try
{
TableQuery <T> cloudTableQuery = filter == null
? new TableQuery <T>()
: new TableQuery <T>().Where(filter);
try
{
Func <Task <List <T> > > executeQueryHandleContinuations = async() =>
{
TableQuerySegment <T> querySegment = null;
var list = new List <T>();
//ExecuteSegmentedAsync not supported in "WindowsAzure.Storage": "7.2.1" yet
while (querySegment == null || querySegment.ContinuationToken != null)
{
querySegment = await Table.ExecuteQuerySegmentedAsync(cloudTableQuery, querySegment?.ContinuationToken);
list.AddRange(querySegment);
}
return(list);
};
#if !ORLEANS_TRANSACTIONS
IBackoffProvider backoff = new FixedBackoff(this.StoragePolicyOptions.PauseBetweenOperationRetries);
List <T> results = await AsyncExecutorWithRetries.ExecuteWithRetries(
counter => executeQueryHandleContinuations(),
this.StoragePolicyOptions.MaxOperationRetries,
(exc, counter) => AzureTableUtils.AnalyzeReadException(exc.GetBaseException(), counter, TableName, Logger),
this.StoragePolicyOptions.OperationTimeout,
backoff);
#else
List <T> results = await executeQueryHandleContinuations();
#endif
// Data was read successfully if we got to here
return(results.Select(i => Tuple.Create(i, i.ETag)).ToList());
}
catch (Exception exc)
{
// Out of retries...
var errorMsg = $"Failed to read Azure storage table {TableName}: {exc.Message}";
if (!AzureTableUtils.TableStorageDataNotFound(exc))
{
Logger.Warn((int)Utilities.ErrorCode.AzureTable_09, errorMsg, exc);
}
throw new OrleansException(errorMsg, exc);
}
}
finally
{
CheckAlertSlowAccess(startTime, operation);
}
}
/// <summary>
/// Read a single table entry from the storage table.
/// </summary>
/// <param name="partitionKey">The partition key for the entry.</param>
/// <param name="rowKey">The row key for the entry.</param>
/// <returns>Value promise for tuple containing the data entry and its corresponding etag.</returns>
public async Task <Tuple <T, string> > ReadSingleTableEntryAsync(string partitionKey, string rowKey)
{
const string operation = "ReadSingleTableEntryAsync";
var startTime = DateTime.UtcNow;
if (Logger.IsEnabled(LogLevel.Trace))
{
Logger.Trace("{0} table {1} partitionKey {2} rowKey = {3}", operation, TableName, partitionKey, rowKey);
}
T retrievedResult = default(T);
try
{
try
{
string queryString = TableQueryFilterBuilder.MatchPartitionKeyAndRowKeyFilter(partitionKey, rowKey);
var query = new TableQuery <T>().Where(queryString);
TableQuerySegment <T> segment = await Table.ExecuteQuerySegmentedAsync(query, null);
retrievedResult = segment.Results.SingleOrDefault();
}
catch (StorageException exception)
{
if (!AzureTableUtils.TableStorageDataNotFound(exception))
{
throw;
}
}
//The ETag of data is needed in further operations.
if (retrievedResult != null)
{
return(new Tuple <T, string>(retrievedResult, retrievedResult.ETag));
}
if (Logger.IsEnabled(LogLevel.Debug))
{
Logger.Debug("Could not find table entry for PartitionKey={0} RowKey={1}", partitionKey, rowKey);
}
return(null); // No data
}
finally
{
CheckAlertSlowAccess(startTime, operation);
}
}
public async Task <GrainStateRecord> Read(string partitionKey, string rowKey)
{
if (logger.IsEnabled(LogLevel.Trace))
{
logger.Trace((int)AzureProviderErrorCode.AzureTableProvider_Storage_Reading, "Reading: PartitionKey={0} RowKey={1} from Table={2}", partitionKey, rowKey, TableName);
}
try
{
Tuple <DynamicTableEntity, string> data = await tableManager.ReadSingleTableEntryAsync(partitionKey, rowKey).ConfigureAwait(false);
if (data == null || data.Item1 == null)
{
if (logger.IsEnabled(LogLevel.Trace))
{
logger.Trace((int)AzureProviderErrorCode.AzureTableProvider_DataNotFound, "DataNotFound reading: PartitionKey={0} RowKey={1} from Table={2}", partitionKey, rowKey, TableName);
}
return(null);
}
DynamicTableEntity stateEntity = data.Item1;
var record = new GrainStateRecord {
Entity = stateEntity, ETag = data.Item2
};
if (logger.IsEnabled(LogLevel.Trace))
{
logger.Trace((int)AzureProviderErrorCode.AzureTableProvider_Storage_DataRead, "Read: PartitionKey={0} RowKey={1} from Table={2} with ETag={3}", stateEntity.PartitionKey, stateEntity.RowKey, TableName, record.ETag);
}
return(record);
}
catch (Exception exc)
{
if (AzureTableUtils.TableStorageDataNotFound(exc))
{
if (logger.IsEnabled(LogLevel.Trace))
{
logger.Trace((int)AzureProviderErrorCode.AzureTableProvider_DataNotFound, "DataNotFound reading (exception): PartitionKey={0} RowKey={1} from Table={2} Exception={3}", partitionKey, rowKey, TableName, LogFormatter.PrintException(exc));
}
return(null); // No data
}
throw;
}
}