Communication of multiple clients through a service.

edit

Hi guys, i am new to ROS and i would like to know if it is possible for a service to save the response of a client and pass it to the next client. And if it is possible how would it be done? As i see it the client should take somehow an input of type service.srv which would contain the saved response but i haven't found anything similar to this. This is my code for the server and the clients. My second client is the same except from the variable id which is given the value 2

server

#include "ros/ros.h"
#include "two_clients/Publish_table.h"
#include "stdlib.h"
#include "time.h"
bool add(two_clients::Publish_table::Request &req,two_clients::Publish_table::Response &res){
    int i;
    for(i=0;i<9;i++){
      res.old_table[i]=req.new_table[i];
      printf("%u\n", res.old_table[i]);
    }
    printf("\n");
  res.table_incomplete=false;
  for(i=0;i<9;i++){
    if(res.old_table[i]==0){
      res.table_incomplete=true;
    }
  }
  if(res.table_incomplete==false){
    ros::shutdown();
  }
}

  int main(int argc,char **argv){
  ros::init(argc,argv,"server1");
  ros::NodeHandle n;
  ros::Rate loop_rate(10);
  two_clients::Publish_table a;
  int i;
  for(i=0;i<9;i++){
    a.request.new_table[i]=0;
    a.response.old_table[i]=0;
  }
  while(ros::ok()){
    ros::ServiceServer service=n.advertiseService("com",add);
    printf("Ready for next client \n " );
    ros::spin();
  }
  return 0;
}

client

#include "ros/ros.h"
#include "two_clients/Publish_table.h"
#include "stdlib.h"
#include "time.h"

int main(int argc,char **argv){
  ros::init(argc,argv,"client_1");
  ros::NodeHandle n;
  ros::ServiceClient client=n.serviceClient<two_clients::Publish_table>("com");
  two_clients::Publish_table srv;
  int i, id ;
  id=1;
  srand(time(NULL));
  while(ros::ok()){
    bool tmp=true;
    while(tmp){
      i=rand()%9;
      if(srv.response.old_table[i]==0){
        srv.request.new_table[i]=id;
        tmp=false;
      }
    }
    if(client.call(srv)){
      printf("Client : %u added to the table at position : %u \n", id,i);
    }
    else{
      ROS_ERROR("Failed to call service com");
      return 1;
    }
  }
  return 0;

}

uint8[9] new_table
---
bool table_incomplete
uint8[9] old_table

launch file

<launch>
  <node
    name="server1"
    pkg="two_clients"
    type="server1"
    output="screen"
  />
  <node
    name="client1"
    pkg="two_clients"
    type="client1"
    output="screen"
  />
  <node
    name="client2"
    pkg="two_clients"
    type="client2"
    output="screen"
  />

</launch>