/// <summary>
/// Creates and initializes a retryable read operation context.
/// </summary>
/// <param name="binding">The binding.</param>
/// <param name="retryRequested">if set to <c>true</c> [retry requested].</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A retryable read context.</returns>
public static async Task <RetryableReadContext> CreateAsync(IReadBinding binding, bool retryRequested, CancellationToken cancellationToken)
{
var context = new RetryableReadContext(binding, retryRequested);
try
{
await context.InitializeAsync(cancellationToken).ConfigureAwait(false);
if (ChannelPinningHelper.PinChannelSourceAndChannelIfRequired(
context.ChannelSource,
context.Channel,
context.Binding.Session,
out var pinnedChannelSource,
out var pinnedChannel))
{
context.ReplaceChannelSource(pinnedChannelSource);
context.ReplaceChannel(pinnedChannel);
}
return(context);
}
catch
{
context.Dispose();
throw;
}
}
public static async Task <TResult> ExecuteAsync <TResult>(IRetryableReadOperation <TResult> operation, RetryableReadContext context, CancellationToken cancellationToken)
{
if (!ShouldReadBeRetried(context))
{
return(await operation.ExecuteAttemptAsync(context, attempt : 1, transactionNumber : null, cancellationToken).ConfigureAwait(false));
}
var initialServerVersion = context.Channel.ConnectionDescription.ServerVersion;
Exception originalException;
try
{
return(await operation.ExecuteAttemptAsync(context, attempt : 1, transactionNumber : null, cancellationToken).ConfigureAwait(false));
}
catch (Exception ex) when(RetryabilityHelper.IsRetryableReadException(ex))
{
originalException = ex;
}
try
{
context.ReplaceChannelSource(context.Binding.GetReadChannelSource(cancellationToken));
context.ReplaceChannel(context.ChannelSource.GetChannel(cancellationToken));
}
catch
{
throw originalException;
}
if (context.Channel.ConnectionDescription.ServerVersion < initialServerVersion)
{
throw originalException;
}
if (!AreRetryableReadsSupported(context))
{
throw originalException;
}
try
{
return(await operation.ExecuteAttemptAsync(context, attempt : 2, transactionNumber : null, cancellationToken).ConfigureAwait(false));
}
catch (Exception ex) when(ShouldThrowOriginalException(ex))
{
throw originalException;
}
}
public static TResult Execute <TResult>(IRetryableReadOperation <TResult> operation, RetryableReadContext context, CancellationToken cancellationToken)
{
if (!ShouldReadBeRetried(context))
{
return(operation.ExecuteAttempt(context, attempt: 1, transactionNumber: null, cancellationToken));
}
Exception originalException;
try
{
return(operation.ExecuteAttempt(context, attempt: 1, transactionNumber: null, cancellationToken));
}
catch (Exception ex) when(RetryabilityHelper.IsRetryableReadException(ex))
{
originalException = ex;
}
try
{
context.ReplaceChannelSource(context.Binding.GetReadChannelSource(cancellationToken));
context.ReplaceChannel(context.ChannelSource.GetChannel(cancellationToken));
}
catch
{
throw originalException;
}
try
{
return(operation.ExecuteAttempt(context, attempt: 2, transactionNumber: null, cancellationToken));
}
catch (Exception ex) when(ShouldThrowOriginalException(ex))
{
throw originalException;
}
}
