vibed_test2/vtest2/source/test3.d

alias uint8  = ubyte;

import std.stdio;
import std.concurrency : receive, receiveOnly, receiveTimeout, send, spawn, thisTid, Tid;
import core.time : Duration, dur;
import core.thread : Thread;

Tid worker_ticker;
Tid[4] workers_tids;


struct Msg1{
  uint8 command;
}

struct Msg2{
  Tid sender;
  string client_id;
}

struct Msg21{
  uint8 command;
  string client_id;
}

struct Msg3{
  Tid sender;
  uint8 command;
  string client_id;
}



void test3_worker(uint8 n){
  writeln("started worker = ", n);
  bool go_work = true;
  
  // https://dlang.org/phobos/std_concurrency.html#.receive
  while(go_work){
    //Thread.sleep(dur!"seconds"(120));
    receive(
      (Msg1 m) =>  writeln("got Msg1: command = ", m.command),
      (Msg2 m){ writeln("got Msg2: from ", m.sender, ", client_id = ", m.client_id); send(m.sender, "Msg2 = ok"); },
      (Msg21 m) => writeln("got Msg21: command = ", m.command, ", client_id = ", m.client_id),
      (Msg3 m){ writeln("got Msg3: from ", m.sender, ", command ", m.command); send(m.sender, "Msg3 = ok"); go_work = false; }
    );
  }
  writeln("stopped worker = ", n); // unreachable
}


void test3_ticker(){
  writeln("started ticker");
  bool go_work = true;
  uint8 counter = 0;
  
  while(go_work){
    //receive(
    receiveTimeout(dur!"seconds"(1),
      (uint8 msg){ if(msg == 0){ writeln("ticker stop command received"); go_work = false; } }
    );
    
    counter += 1;
    if(counter % 5 == 0){
      counter = 0;
      writeln("tick (5 seconds passed)");
    }
    
    Thread.sleep(dur!"seconds"(1));
  }
}


void test3_spawner(){
  worker_ticker = spawn(&test3_ticker);
  
  uint8 i = 1;
  workers_tids[0] = spawn(&test3_worker, i);
  string answer;
  
  //Thread.sleep(dur!"seconds"(30));
  Thread.sleep(dur!"seconds"(3));
  
  send(workers_tids[0], Msg1(42)); // async command ?
  
  send(workers_tids[0], Msg2(thisTid, "client_123"));
  answer = receiveOnly!string();
  writeln("answer = ", answer);
  
  send(workers_tids[0], Msg21(5, "client_456"));
  send(workers_tids[0], Msg3(thisTid, 99, "client_789"));
  answer = receiveOnly!string();
  writeln("answer = ", answer);
  
  Thread.sleep(dur!"seconds"(25));
  
  uint8 stop_command = 0;
  send(worker_ticker, stop_command); // send stop command for ticker worker
  
  writeln("the end");
}


/*
// message passing (sync + responce) + ticker with stop command + app ok stop

> make run
./vtest2
started ticker
started worker = 1
got Msg1: command = 42
got Msg2: from Tid(7ff9edfa48f0), client_id = client_123
answer = Msg2 = ok
got Msg21: command = 5, client_id = client_456
got Msg3: from Tid(7ff9edfa48f0), command 99
stopped worker = 1
answer = Msg3 = ok
tick (5 seconds passed)
tick (5 seconds passed)
the end
ticker stop command received
tick (5 seconds passed)
hello here!

*/