Harpoon.h

/*
 * File:   Harpoon.h
 * Author: Ryan Kophs
 *
 * Created on December, 2014
 */


#pragma once
#include <string>
#include <vector>
#include <czmq.h>

/** Harpoon-Kraken is a PipeLine communication pattern used to
*  stream files or plain data from a server to a client. 
* 
* The Client: Here called Harpoon connects (harpoon hit) the 
* Kraken (server).  
* 
* The Harpoon keeps receiving/pulling data from the Kraken until 
* mission achieved (Kraken is dead...) all the data is received. 
* 
* Originally this was described at zeromq.org as fileio model:
* http://zguide.zeromq.org/c:fileio3
*/
class Harpoon {
public: 

   enum class Spear : std::int8_t { MISS = -1, IMPALED = 0 };
   enum class Battling : std::int8_t { TIMEOUT = -2, INTERRUPT = -1, VICTORIOUS = 0, CONTINUE = 1, CANCEL = 2 };

   Harpoon();

   Spear Aim(const std::string& location);
   void MaxWaitInMs(const int timeoutMs);
   Battling Heave(std::vector<uint8_t>& data);
   Battling Cancel();
   virtual ~Harpoon();

   std::string EnumToString(Battling type) const;

protected:
   Battling PollTimeout(int timeoutMs);
   void RequestChunks();
   void FreeChunk();
   
private:
   void* mDealer;
   zctx_t* mCtx;
   size_t mQueueLength;
   int mTimeoutMs;
   size_t mCredit;
   size_t mOffset;
   zframe_t *mChunk;
};