title: Calling Rest API from mapreduce (reducer)
body: <p>Do you see any problem of calling a REST POST API from mapreduce reducer method?
  The Api is low latency :20 milliseconds per call/key.
  There is time-out if a call takes more than defined.
  The API output is used by further logic in the reducer. </p>
  
  <p>Thank you in advance
  Vladek</p>