tchannel close states / transitions

gistfile1.txt

Close
  close("user initiated")

close
  sets state to connectionStartClose
  causes checkExchanges to go to close states

readFrames:
  connectionError if closeNetwork ISNT called

writeFrames:
  when stopCh closes, calls closeNetwork

connectionError:
  calls close
  STOPS exchanges
  stopHealthCheck

checkExchanges:
  changes conn state based on exchanges
  call close(stopCh) which will cause writeFrames to call closeNetwork

closeSendCh:
  loop till pendingMethods is 0
  closes stopCh  [Not sure if loop required above, since we don't touch sendCh]
      improvement mentioned in https://github.com/uber/tchannel-go/pull/388/commits/93ef5c112c8b321367ae52d2bd79396e2e874f31

closeNetwork:
  tcpConn.Close (causes write/read to get errors)
  stopHealthCheck
  typically last thing called..


closeTimeout:
  (don't call close again)
  

close timeout:
  




Normally:

Close
  close()
  causes checkExchanges to close stopCh
  causes writeFrames signal
  causes closeNetwork
  causes tcp conn to close, and stop health check
  causes readFrames to unblock


Conn error
  readFrames gets error, calls
  connectionError which calls
  close
  stops all exchanges
  stopHealthCheck
  checkExchanges will now close everything?