// Recursive, retry-logic, state-machine function
public async Task <Todo> Start()
{
// let's keep track of our function's status
Console.WriteLine();
Console.WriteLine("status: " + Status.ToString());
Console.WriteLine("retries: " + Retries.ToString());
// if Start() is called with the CircuitBreaker status being OPEN
if (Status == Status.OPEN)
{
try
{
// lets do our initial call
return(await Call().ConfigureAwait(false));
}
catch (Exception badResponse)
{
// do something with bad_response...
Console.WriteLine(badResponse.Message);
// set status to HALFOPEN because our initial request failed
Status = Status.HALFOPEN;
Retries++;
return(await Start().ConfigureAwait(false)); // retry with our Status being HALFOPEN
}
}
// if Start() is called with the CircuitBreaker status being HALFOPEN
if (Status == Status.HALFOPEN)
{
Console.WriteLine("TIMEOUT...");
Thread.Sleep(TimeOut);
try
{
// try a call again
return(await Call().ConfigureAwait(false));
}
catch
{
if (Retries < RetryCount) // did we retry too many times already?
{
Retries++;
return(await Start().ConfigureAwait(false)); // Start this function again with the same status HALFOPEN
}
// looks like we retried too many times, time to set status to CLOSED
Status = Status.CLOSED;
return(await Start().ConfigureAwait(false));
}
}
// if Start() is called with the CircuitBreaker status being CLOSED
if (Status == Status.CLOSED)
{
// we throw our final error message
throw new Exception($"CircuitBreaker failed for { Url} : { Retries} " +
$"times: TimeOut { TimeOut}");
}
return(await Start().ConfigureAwait(false)); // this should never be reached, but acts as a safety-net
}