private static Task BackoffAsync(RetryContext context)
{
TimeSpan delay = TimeSpan.FromMilliseconds(10 * context.Iteration);
Log("Backing off for {0:0.000} seconds.", delay.TotalSeconds);
return(Task.Delay(delay));
}
private static async Task ReadFileAsync(RetryContext context)
{
try
{
using (FileStream stream = new FileStream("test.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite, 256, true))
{
byte[] buffer = new byte[4];
int bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length);
if (bytesRead == buffer.Length)
{
string text = Encoding.ASCII.GetString(buffer);
Log("ReadFileAsync read '{0}'", text);
context.Add("Text", text);
}
else
{
Log("ReadFileAsync read only {0} bytes.", bytesRead);
}
}
}
catch (Exception e)
{
Log("ReadFileAsync error: {0}: {1}", e.GetType().Name, e.Message);
throw;
}
}
public async Task <RetryContext> ExecuteAsync()
{
RetryContext context = new RetryContext();
bool shouldRetry = false;
TimeSpan startTime = this.Timer.Elapsed;
do
{
try
{
if (shouldRetry)
{
await this.BeforeRetry(context);
}
context.Exception = null;
context.ElapsedTime = this.Timer.Elapsed - startTime;
await this.func(context);
}
catch (Exception e)
{
context.Exception = new AggregateException(e);
}
context.ElapsedTime = this.Timer.Elapsed - startTime;
context.Succeeded = this.Succeeded(context);
shouldRetry = this.ShouldRetry(context);
++context.Iteration;
}while (!context.Succeeded && shouldRetry);
return(context);
}
public static async Task AddAsync <TResult>(this RetryContext context, string name, Task <TResult> task)
{
TResult result = await task;
context.Add(name, result);
}