Linux C++ zookeeper创建临时节点类封装

至于zookeeper环境搭建和c++ client端的编译，此处就不再赘述了。直接上实现代码吧。

主要功能：zookeeper创建临时节点，可用于判断程序是否存在。

实现思想：实现CZkCreateEphemeralNode类，在构造函数中创建临时节点，析构函数中删除或者不删除都是可以的。那么，定义一个全局对象或者NEW一个对象即可。

CZkCreateEphemeralNode.h

/************************************************************************/ /* zookeeper Create Ephemeral Node */ /************************************************************************/ #ifndef __CZKCREATETEMPORARYNODE_H__ #define __CZKCREATETEMPORARYNODE_H__ #include <string> #include "zookeeper.h" #include "zookeeper_log.h" class CZkCreateEphemeralNode { public: CZkCreateEphemeralNode(std::string m_strHost, int m_nTimeOut, std::string strPath, std::string strValue, std::string& strError); ~CZkCreateEphemeralNode(); private: CZkCreateEphemeralNode(); CZkCreateEphemeralNode(const CZkCreateEphemeralNode&); private: static void zktest_watcher_g(zhandle_t* zh, int type, int state, const char* path, void* watcherCtx); static void zktest_dump_stat(const struct Stat* stat); static void zktest_stat_completion(int rc, const struct Stat* stat, const void* data); static void zktest_void_completion(int rc, const void* data); static void zktest_string_completion(int rc, const char* name, const void* data); public: static int zkOpen(zhandle_t** zkHandle, std::string strHost, int nTimeOut); static int zkCreate(zhandle_t* zkHandle, std::string strPath, std::string strValue); static int zkClose(zhandle_t** zkHandle); //static int zkOpen(std::string strHost, int nTimeOut); //static int zkCreate(std::string strPath, std::string strValue); //static int zkClose(); private: std::string m_strHost; int m_nTimeOut; std::string m_strPath; std::string m_strValue; zhandle_t* m_zkHandle; }; #endif CZkCreateEphemeralNode.cpp

#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <ctime> #include <string> #include <string.h> #include "CZkCreateEphemeralNode.h" #include <iostream> using namespace std; void CZkCreateEphemeralNode::zktest_watcher_g(zhandle_t* zh, int type, int state, const char* path, void* watcherCtx) { printf("Something happened.\n"); printf("type: %d\n", type); printf("state: %d\n", state); printf("path: %s\n", path); printf("watcherCtx: %s\n", (char*)watcherCtx); } void CZkCreateEphemeralNode::zktest_dump_stat(const struct Stat* stat) { char tctimes[40]; char tmtimes[40]; time_t tctime; time_t tmtime; if (!stat) { fprintf(stderr, "null\n"); return; } tctime = stat->ctime / 1000; tmtime = stat->mtime / 1000; ctime_r(&tmtime, tmtimes); ctime_r(&tctime, tctimes); fprintf(stderr, "\tctime = %s\tczxid=%llx\n" "\tmtime=%s\tmzxid=%llx\n" "\tversion=%x\taversion=%x\n" "\tephemearalOwner=%llx\n", tctimes, stat->czxid, tmtimes, stat->mzxid, (unsigned int)stat->version, (unsigned int)stat->aversion, stat->ephemeralOwner ); } void CZkCreateEphemeralNode::zktest_stat_completion(int rc, const struct Stat* stat, const void* data) { fprintf(stderr, "%s: rc=%d Stat:\n", (char*)data, rc); zktest_dump_stat(stat); } void CZkCreateEphemeralNode::zktest_void_completion(int rc, const void* data) { fprintf(stderr, "[%s]: rc = %d\n", (char*)(data == 0 ? "null" : data), rc); } void CZkCreateEphemeralNode::zktest_string_completion(int rc, const char* name, const void* data) { fprintf(stderr, "[%s]: rc = %d\n", (char*)(data == 0 ? "null" : data), rc); if (!rc) { fprintf(stderr, "\tname = %s\n", name); } } int CZkCreateEphemeralNode::zkOpen(zhandle_t** zkHandle, std::string strHost, int nTimeOut) { if (strHost.length() < 0 || nTimeOut < 0) { fprintf(stderr, "Init failed.Param error.\n"); return -1; } zoo_set_debug_level(ZOO_LOG_LEVEL_WARN); *zkHandle = zookeeper_init(strHost.c_str(), zktest_watcher_g, nTimeOut, 0, (void*)"hello zookeeper.", 0); if (*zkHandle == nullptr) { fprintf(stderr, "Error when connecting to zookeeper servers...\n"); return -1; } return 0; } int CZkCreateEphemeralNode::zkCreate(zhandle_t* zkHandle, std::string strPath, std::string strValue) { if ( strPath.length() <= 0 ) { fprintf(stderr, "Create failed.Param error.\n"); return -1; } cout << "zoo_acreate: path:" << strPath << ", value:" << strValue << endl; int nRet = zoo_acreate(zkHandle, strPath.c_str(), strValue.c_str(), strValue.length(), &ZOO_OPEN_ACL_UNSAFE, ZOO_EPHEMERAL, zktest_string_completion, "acreate"); if (nRet) { fprintf(stderr, "Error %d for %s\n", nRet, "acreate"); exit(EXIT_FAILURE); } nRet = 0; sleep(1); nRet = zoo_aexists(zkHandle, strPath.c_str(), 1, zktest_stat_completion, "aexists"); if (nRet) { fprintf(stderr, "Error %d for %s", nRet, "aexists"); exit(EXIT_FAILURE); } return 0; } int CZkCreateEphemeralNode::zkClose(zhandle_t** zkHandle) { if (*zkHandle) { zookeeper_close(*zkHandle); *zkHandle = nullptr; } return 0; } CZkCreateEphemeralNode::CZkCreateEphemeralNode(std::string strHost , int nTimeOut , std::string strPath , std::string strValue , std::string& strError ) : m_strHost(strHost) , m_nTimeOut(nTimeOut) , m_strPath(strPath) , m_strValue(strValue) , m_zkHandle(nullptr) { strError = ""; if (m_strHost.length() <= 0 || m_nTimeOut <= 0 || m_strPath.length() <= 0 || m_strValue.length() <= 0 ) { strError = "Param error."; } int nRet = CZkCreateEphemeralNode::zkOpen(&m_zkHandle, m_strHost, nTimeOut); if ( nRet != 0 ) { strError = "zkOpen fialed."; } else { nRet = CZkCreateEphemeralNode::zkCreate(m_zkHandle, m_strPath, m_strValue); if (nRet != 0) { strError = "zkCreate fialed."; } } } CZkCreateEphemeralNode::~CZkCreateEphemeralNode() { zkClose(&m_zkHandle); } CZkCreateEphemeralNode::CZkCreateEphemeralNode() { } CZkCreateEphemeralNode::CZkCreateEphemeralNode(const CZkCreateEphemeralNode&) { } main.cpp

#include "CZkCreateEphemeralNode.h" #include <string.h> #include <iostream> using namespace std; int main() { /************************************************************************/ /* 二种方式：1、new的方式创建CZkCreateEphemeralNode */ /* 2、定义全局变量CZkCreateEphemeralNode */ /************************************************************************/ std::string strError; CZkCreateEphemeralNode* pZk = new CZkCreateEphemeralNode("127.0.0.1:2181,127.0.0.1:2182", 3000, "/xyz_test/test_client", "test", strError); if ( strError.length() > 0 ) { wcout << L"CZkCreateEphemeralNode error." << endl; } //g_Zk变量必须在程序的整个生命周期（建议使用全局变量） CZkCreateEphemeralNode g_Zk("127.0.0.1:2181,127.0.0.1:2182", 3000, "/xyz_test/test_client1", "test", strError); if (strError.length() > 0) { wcout << L"CZkCreateEphemeralNode error." << endl; } char ch; cin >> ch; return 0; } Makefile

OBJECTS = main.o CZkCreateEphemeralNode.o DES = visZkCreateEphemeralNode CC = g++ -std=c++11 INC = -I /usr/local/include/zookeeper/ LINK = -L /usr/local/lib/ -lzookeeper_mt -DTHREADED all : $(DES) $(DES) : $(OBJECTS) $(CC) -o $(DES) $(OBJECTS) $(LINK) $(INC) main.o : main.cpp $(CC) -o main.o -c main.cpp $(INC) -g CZkCreateEphemeralNode.o : CZkCreateEphemeralNode.cpp CZkCreateEphemeralNode.h $(CC) -o CZkCreateEphemeralNode.o -c CZkCreateEphemeralNode.cpp $(INC) -g install: clean: rm -rf $(DES) $(OBJECTS)

CZkCreateEphemeralNode