Poco库完全使用手册

什么是POCO库？

POCO库是强大的的跨平台C++库，可以用来编写多平台的网络应用程序，这些平台包括桌面端、服务端、移动端、IOT(物联网)、嵌入式系统等。总的来说是一个非常强大的综合性库。

为什么使用Poco库？

1.支持跨平台

2.性能表现优异

3.API使用方便,便于上手

4.库可以拆分使用,容易实现轻量化调用

5.功能模块丰富

6.Poco C++库是在Boost软件许可证下授权的，既可以用来开发非商业应用，也可以用来开发商业应用。可以说是可以自由使用的了。

POCO库都能做哪些事？

根据Poco官方文档介绍Poco库支持的功能组如下：

1.类型和字节序操作

2.错误处理和调试

3.内存管理

4.字符串和文本的格式化

5.平台和环境的操作和处理

6.随机数生成和各种哈希算法

7.时间和日期处理

8.文件操作系统处理

9.通知和事件

10.各种流处理

11.日志操作

12.动态的库操作

13.进程管理

14.url和uuid的生成和操作

15.XML和Json文件操作

16.网络编程

17.客户端程序和网络程序的编写

18.文件系统的支持和配置

19.日志系统的配置

总的来说就是能用到的功能poco库都支持，可以说是非常强大了。

源码下载和库编译？

Poco库的官网地址

https://pocoproject.org/index.html

Poco库的项目地址

https://github.com/pocoproject/poco/tree/master

Poco库可以根据使用需求不同，编译成静态库或者动态库，编译方法很简单，这里就不再做详细介绍了。

Poco库常用功能:

MD5值计算、Base64加密计算、HMAC-MD5计算

#include <iostream>
#include <fstream>
#include <sstream>//MD5值的计算
#include "Poco\MD5Engine.h"
#include "Poco\DigestStream.h"
#include "Poco\StreamCopier.h"using Poco::DigestEngine;
using Poco::MD5Engine;
using Poco::DigestOutputStream;
using Poco::StreamCopier;//base64的计算
#include "Poco\Base64Decoder.h"
#include "Poco\StreamCopier.h"
#include "Poco\Base64Encoder.h"using Poco::Base64Encoder;
using Poco::StreamCopier;
using Poco::Base64Decoder;//计算HMAC-MD5值
#include "Poco/HMACEngine.h"
#include "Poco/MD5Engine.h"
#include "Poco/DigestStream.h"
#include "Poco/StreamCopier.h"
#include <fstream>
#include <iostream>using Poco::DigestEngine;
using Poco::HMACEngine;
using Poco::MD5Engine;
using Poco::DigestOutputStream;
using Poco::StreamCopier;using namespace std;
int main(int argc, char** argv)
{//计算文件的MD5值ifstream inputStream("test.txt", ios::binary);MD5Engine md5;DigestOutputStream dos(md5);StreamCopier::copyStream(inputStream, dos);dos.close();cout << DigestEngine::digestToHex(md5.digest()) << std::endl;cout << "完成md5值的计算" << endl;//计算字符串的MD5值std::string INPUT_STRING = "hello";stringstream stringStream(INPUT_STRING);StreamCopier::copyStream(stringStream, dos);dos.close();cout << DigestEngine::digestToHex(md5.digest()) << std::endl;cout << "字符串md5值计算完毕" << endl;//对文件进行base64加密ifstream base64EncodeInputStream("test.txt", ios::binary);ofstream base64EncodeOutputStream("encoderesult.txt");Base64Encoder encoder(base64EncodeOutputStream);StreamCopier::copyStream(base64EncodeInputStream, encoder);cout << "完成base64加密" << endl;encoder.close();//对文件进行解密ofstream base64DecodeOutputStream("decoderesult.txt");ifstream base64DecodeInputStream("encoderesult.txt");Base64Decoder decoder(base64DecodeInputStream);StreamCopier::copyStream(decoder,base64DecodeOutputStream);//对字符串进行加密stringstream strbase64encodeinputstream(string("ceshibase64"));string strbase64encodeoutputStr;stringstream strencodeOutputStream;Base64Encoder stringencodr(strencodeOutputStream);StreamCopier::copyStream(strbase64encodeinputstream, stringencodr);stringencodr.close();strencodeOutputStream >> strbase64encodeoutputStr;//对字符串进行解密stringstream strdecodeInputstream(strbase64encodeoutputStr);stringstream strdecodeOutputstream;string decodeResult;Base64Decoder stringdecoder(strdecodeInputstream);StreamCopier::copyStream(stringdecoder, strdecodeOutputstream);strdecodeOutputstream >> decodeResult;//计算文件的HMAC-MD5值string passphrase("hmac-key");ifstream hmacinputStream("test.txt", ios::binary);HMACEngine<MD5Engine> hmac(passphrase);DigestOutputStream hmacdos(hmac);StreamCopier::copyStream(hmacinputStream, hmacdos);hmacdos.close();cout << DigestEngine::digestToHex(hmac.digest()) << std::endl;//计算字符串的HMAC-MD5值stringstream hmacStrinputStream("ceshishiyong");HMACEngine<MD5Engine> hStrmac(passphrase);DigestOutputStream hmaStrcdos(hStrmac);StreamCopier::copyStream(hmacStrinputStream, hmaStrcdos);hmaStrcdos.close();cout << DigestEngine::digestToHex(hStrmac.digest()) << std::endl;}

使用Poco库来搭建服务程序

服务的程序类似于一个线程池程序，每个人物都是是一个子线程运行在对应的线程池当中。线程池的程序类似于下面:

#include "Poco/Util/ServerApplication.h"
#include "Poco/Logger.h"class MyServer : public Poco::Util::ServerApplication
{
public:MyServer();virtual ~ MyServer();// Poco::Util::ServerApplication overridables
public:virtual void initialize(Poco::Util::Application &self) override;virtual void uninitialize() override;virtual int main(const std::vector<std::string>& args) override;private:void createLogDir();
};

线程池管理器就是所谓的服务器主程序，主程序继承自Poco::Utils::ServerApplication

主要重写三个接口

//initialize是初始化接口，在初始化服务器的时候被调用，做些初始化操作
virtual void initialize(Poco::Util::Application &self) override;
//uninitialize是清理操作，在服务器终止的时候被调用，做一些清理的操作
virtual void uninitialize() override;
//main是主函数主要负责对应的主程序
virtual int main(const std::vector<std::string>& args) override;

#include "MyServer.h"
#include "Poco/TaskManager.h"
#include "Poco/AutoPtr.h"
#include "Poco/ConsoleChannel.h"
#include "Poco/FileChannel.h"
#include "Poco/SplitterChannel.h"
#include "Poco/FormattingChannel.h"
#include "Poco/PatternFormatter.h"
#include "Poco/SimpleFileChannel.h"#include <Shlobj.h>
#include <Shlwapi.h>
#include <WinBase.h>void MyServer::initialize(Poco::Util::Application &self)
{ServerApplication::initialize(self);logger().information("Service is starting up");
}
void MyServer::uninitialize()
{logger().information("Service is shutting down");ServerApplication::uninitialize();
}int  MyServer::main(const std::vector<std::string>& args)
{ HANDLE hMutext = CreateMutexA(NULL, TRUE, " My-service-mutext");logger().information("Service is running as %s ...", config().getBool("application.runAsService", false) ? std::string("service") : std::string("command line"));Poco::TaskManager taskManager;//版本更新taskManager.start(new UpdateTask());//等待任务取消waitForTerminationRequest();taskManager.cancelAll();//等待取消操作完成taskManager.joinAll();ReleaseMutex(hMutext);hMutext = INVALID_HANDLE_VALUE;return Application::EXIT_OK;
}

服务器中的每个人物都是一个线程类似于QT中的QRunnable

Poco中的程序中的每一个人物都继承于Task类，

#include "Poco/Task.h"
class MyUpdateTask : public Poco::Task
{
public:MyUpdateTask();virtual ~ MyUpdateTask();// Poco::Task overridables
public://runTask是入口函数virtual void runTask() override;
private:
};

主函数中启动服务程序的方法

#include "MyServer.h"
#include <iostream>#ifdef _DEBUG
int main()
{HYPYServer server;server.main(std::vector<std::string>());return 0;
}
#else
POCO_SERVER_MAIN(HYPYServer)
#endif

使用Poco库进行Https请求访问服务器

https Get 请求

bool UpdateTask::fetchUpdateInfoFromHTTPServer()
{//请求的参数std::string arg1 = "1";std::string arg2 = "2";std::string arg3 = "3";//拼接对应的请求Config config;std::string path = "/api/v1/update";Poco::URI uri;uri.setScheme(config.getServerScheme());uri.setHost(config.getServerAddr());uri.setPort(config.getServerPort());uri.setPath(path);uri.addQueryParameter("arg1", arg1);uri.addQueryParameter("arg2", arg2);uri.addQueryParameter("arg3", arg3);Poco::Net::HTTPSClientSession* https_session = OSUtils::CommonUtils::GetHttpsClientSession();https_session->setPort(uri.getPort());https_session->setHost(uri.getHost());std::string pathAndQuery(uri.getPathAndQuery());Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_GET, pathAndQuery,Poco::Net::HTTPMessage::HTTP_1_1);Poco::Net::HTTPResponse response;https_session->sendRequest(request);std::istream &streamIn = https_session->receiveResponse(response);std::ostringstream responseStream;Poco::StreamCopier::copyStream(streamIn, responseStream);m_responseContent = responseStream.str();delete https_session;https_session = nullptr;return response.getStatus() == Poco::Net::HTTPResponse::HTTP_OK;
}

HTTP POST下载请求

int MyUpdateTask::UpdateWork(std::string loginid, std::string clientid, std::string& filePath)
{try{Config config;std::string path = "/api/v1/dict/download";Poco::URI uri;uri.setScheme(config.getServerScheme());uri.setHost(config.getServerAddr());uri.setPort(config.getServerPort());uri.setPath(path);Poco::Net::HTTPSClientSession* https_session = OSUtils::CommonUtils::GetHttpsClientSession();https_session->setHost(uri.getHost());https_session->setPort(uri.getPort());Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_POST, uri.getPathAndQuery(),Poco::Net::HTTPMessage::HTTP_1_1);Poco::Net::HTMLForm form;form.add("loginid", loginid);form.add("clientid", clientid);form.prepareSubmit(request);form.write(https_session->sendRequest(request));Poco::Net::HTTPResponse response;std::istream &streamIn = https_session->receiveResponse(response);if (response.getStatus() != Poco::Net::HTTPResponse::HTTP_OK){delete https_session;https_session = nullptr;return 1;}std::ostringstream responseStream;Poco::StreamCopier::copyStream(streamIn, responseStream);std::string resultStr = responseStream.str();delete https_session;https_session = nullptr;Poco::JSON::Parser parser;auto root = parser.parse(resultStr);Poco::JSON::Object::Ptr objRoot = root.extract<Poco::JSON::Object::Ptr>();if (!objRoot)return 2;int codeResult = objRoot->getValue<int>("code");if (codeResult == 200){dictFilePath = objRoot->getValue<std::string>("result");return 0;}return codeResult;}catch (...){return 1;}
}

https Post MultiPart请求

int MyUpdateTask::UpdateWork(std::string loginid, std::string clientid, std::string path)
{try{//获得对应的请求参数Config config;std::string path = "/api/v1/dict/ceshi";Poco::URI uri;uri.setScheme(config.getServerScheme());uri.setHost(config.getServerAddr());uri.setPort(config.getServerPort());uri.setPath(path);//获得对应的会话客户端Poco::Net::HTTPSClientSession* https_session = OSUtils::CommonUtils::GetHttpsClientSession();https_session->setHost(uri.getHost());https_session->setPort(uri.getPort());//生成对应的请求Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_POST, uri.getPathAndQuery(),Poco::Net::HTTPMessage::HTTP_1_1);request.setContentType("multipart/form-data");//在表单中添加对应的参数和文件Poco::Net::HTMLForm form;form.setEncoding(Poco::Net::HTMLForm::ENCODING_MULTIPART);form.add("loginid", loginid);form.add("clientid", clientid);form.addPart("dict", new Poco::Net::FilePartSource(path));form.prepareSubmit(request);form.write(https_session->sendRequest(request));Poco::Net::HTTPResponse response;std::istream &streamIn = https_session->receiveResponse(response);if (response.getStatus() != Poco::Net::HTTPResponse::HTTP_OK){delete https_session;https_session = nullptr;return 1;}std::ostringstream responseStream;Poco::StreamCopier::copyStream(streamIn, responseStream);std::string resultStr = responseStream.str();delete https_session;https_session = nullptr;Poco::JSON::Parser parser;auto root = parser.parse(resultStr);Poco::JSON::Object::Ptr objRoot = root.extract<Poco::JSON::Object::Ptr>();if (!objRoot)return 2;int codeResult = objRoot->getValue<int>("code");if(codeResult == 200){return 0;}return codeResult;}catch (...){return 1;}
}

通过URL下载文件

Poco::URI uri(addrs.at(index).fileUrl);
Poco::Net::HTTPSClientSession* https_session = OSUtils::CommonUtils::GetHttpsClientSession();
https_session->setPort(uri.getPort());
https_session->setHost(uri.getHost());Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_GET, uri.getPathAndQuery(),Poco::Net::HTTPMessage::HTTP_1_1);
Poco::Net::HTTPResponse response;
https_session->sendRequest(request);
std::istream &streamIn = https_session->receiveResponse(response);
if (response.getStatus() == Poco::Net::HTTPResponse::HTTP_OK)
{}

使用到的生成https请求的客户端

Poco::Net::HTTPSClientSession* OSUtils::CommonUtils::GetHttpsClientSession()
{std::string certificate_path = OSUtils::PathUtils::getCertificatePath();SSLManager::InvalidCertificateHandlerPtr handlerPtr(new AcceptCertificateHandler(false));Context::Ptr context = new Context(Context::TLSV1_2_CLIENT_USE, certificate_path, Poco::Net::Context::VERIFY_NONE, 9);SSLManager::instance().initializeClient(nullptr, handlerPtr, context);HTTPSClientSession *session = new HTTPSClientSession(context);session->setTimeout(5000 * 1000);int timeout_sec = session->getTimeout().seconds();return session;
}

Poco库解压缩文件

ifstream instream(filepath, ios::binary);
Poco::Zip::Decompress decompress(instream, fileDir);
decompress.decompressAllFiles();
instream.close();
File  zip_file(filepath);
if (zip_file.exists())zip_file.remove();