1.项目介绍
该项目是一个基于http和tcp协议自主实现的WebServer,用于实现浏览器对服务器的简单请求,然后接收服务器返回的处理请求数据,目的是为了让学习者更好的对网络连接和相关协议进行理解,同时制作出像网络在线计算机,音视频请求播放,或者类似博客的功能,该醒目利用到的主要技术有网络编程(socket),多线程编程,cgi技术,管道通信等。
2.具体编码实现
2.1 tcp_server
#pragma once
#include <iostream>
#include "LOG.hpp"
#include <sys/types.h>
#include <sys/socket.h>
#include <cstdlib>
#include <cstring>
#include <pthread.h>
#include <netinet/in.h>
#include <arpa/inet.h>#define PORT 8081
#define BACKLOG 5
class TcpServer{private:int listen_sock;int port;static TcpServer* tcpserver;private:TcpServer(int _port = PORT):listen_sock(),port(_port){ }~TcpServer(){}public:static TcpServer* GetInstance(int _port = PORT){static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;if(tcpserver == nullptr){pthread_mutex_lock(&lock);if(tcpserver == nullptr){tcpserver = new TcpServer(_port);tcpserver->InitTcpServer();}pthread_mutex_unlock(&lock);}return tcpserver;}void InitTcpServer(){CreateSock();BindSock();ListenSock();}void CreateSock(){listen_sock = socket(AF_INET,SOCK_STREAM,0);if(listen_sock < 0){LOG(INFO,"Create Sock Unsucess!");exit(1);}int opt = 1;setsockopt(listen_sock,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt));LOG(INFO,"Create Sock Sucess!");}void BindSock(){struct sockaddr_in local;memset(&local,0,sizeof(local));local.sin_family = AF_INET;local.sin_port = htons(port);local.sin_addr.s_addr = INADDR_ANY; //云服务器不可以直接绑定ipif(bind(listen_sock,(struct sockaddr*)&local,sizeof(local))<0){LOG(INFO,"Bind Sock Unsucess!");exit(2);}LOG(INFO,"Bind Sock Sucess!");}void ListenSock(){if(listen(listen_sock,BACKLOG)<0){LOG(INFO,"Listen Sock Unsucess!");exit(3);}LOG(INFO,"Listen Sock Sucess!");}int GetListenSock(){return listen_sock;}};
TcpServer* TcpServer::tcpserver = nullptr;
2.2 http_server
#pragma once
#include "TcpServer.hpp"
#include "Protocol.hpp"
#include "LOG.hpp"
#include "Task.hpp"
#include "ThreadPool.hpp"#define PORT 8081
class HttpServer{private:int sock;int port;int stop;TcpServer* tcpserver;public:HttpServer(int _port = PORT):port(_port),stop(false),tcpserver(nullptr){}void InitHttpServer(){// 防止对端(client and server)断开发送SIGPIPE信号时,执行默认动作signal(SIGPIPE,SIG_IGN);}void Loop(){tcpserver = TcpServer::GetInstance(port);while(!stop){struct sockaddr_in peer;socklen_t len = sizeof(peer);memset(&peer,0,sizeof(peer));sock = accept(tcpserver->GetListenSock(),(struct sockaddr*)&peer,&len);LOG(INFO,"Begin Get A New Link!");if(sock < 0){LOG(INFO,"Accept Socket Unsucess!");continue;}LOG(INFO,"Begin Proess Request!");TASK task(sock);ThreadPool::GetInstance()->PushTask(task);}}~HttpServer(){}
};
2.3 日志系统
#pragma once
#include <string>
#include <iostream>
#include <cstdio>
#include <time.h>
#define INFO 1
#define WARNING 2
#define ERROR 3
#define FATAL 4
#define LOG(level,message) log(#level,message,__FILE__,__LINE__)
void log(std::string level,std::string message,std::string fname,int eline){struct tm t;time_t now = time(NULL);localtime_r(&now,&t);printf("[%-7s][%-4d-%02d-%02d %02d:%02d:%02d][%-30s][%-15s][%-4d]\n",\level.c_str(),t.tm_year+1900,t.tm_mon+1,t.tm_mday,t.tm_hour,t.tm_min,t.tm_sec,\message.c_str(),fname.c_str(),eline);}
2.4 Protocol协议的搭建
class EndPoint{private:int sock;bool stop;HttpRequest http_request;HttpResbonse http_resbonse;public:EndPoint(int _sock):sock(_sock),stop(false){}int IsStop(){return stop;} void RecvHttpRequest(){if((!Recv_Parse_HttpRequest_Line()) && \(!Recv_Parse_HttpRequest_Head()) && \(!Recv_HttpRequest_Body())){}}int Recv_Parse_HttpRequest_Line(){LOG(INFO,"Begin Recv Request"); //recvif(Utility::ReadLine(sock,http_request.request_line)> 0){http_request.request_line.back() = 0;LOG(INFO,http_request.request_line);}else{stop = true;return stop;}//parsestd::stringstream ss(http_request.request_line);ss>>http_request.method>>http_request.uri>>http_request.version;//toupperauto& mt = http_request.method;std::transform(mt.begin(),mt.end(),mt.begin(),::toupper);size_t pos = http_request.path.rfind(".");if(pos != std::string::npos){http_request.suffix = http_request.path.substr(pos+1);}return stop;}int Recv_Parse_HttpRequest_Head(){//recvstd::string line = "";while(true){line.clear();if(Utility::ReadLine(sock,line)<=0){stop = true;return stop;}if(line == "\n"){http_request.blank = line;break;}line.back() = 0;http_request.request_header.push_back(line);LOG(INFO,line);}//parsefor(auto& item:http_request.request_header) {std::string key,value;Utility::CutString(item,key,value,": ");http_request.request_header_kv[key] = value;}return stop;}int Recv_HttpRequest_Body(){auto& mt = http_request.method;if(mt == "POST"){auto item = http_request.request_header_kv.find("Content-Length");if(item != http_request.request_header_kv.end()){http_request.content_length = atoi(item->second.c_str());int size = http_request.content_length;while(size){char ch;size_t s = recv(sock,&ch,1,0);if(s > 0){http_request.request_body.push_back(ch);size--;}else if(s == 0){break;}else {stop = true;return stop;LOG(ERROR,"Recv RequestBody Error");exit(1);}}}}return stop;}void Build_HttpResbonse(){http_request.path = "wwwroot";auto& mt = http_request.method;std::string tmp;struct stat buf;//检查方法是否合法if(mt!= "GET" && mt != "POST"){LOG(INFO,"Request Method Is Not Law!");http_resbonse.status_code = NOT_FOUND;goto END;}if(mt == "GET"){//如果是get方法,检查是否带参size_t pos = http_request.uri.find("?"); if(pos != std::string::npos){Utility::CutString(http_request.uri,tmp,http_request.query,"?");http_request.cgi = true;}else {tmp = http_request.uri;}}else if(mt == "POST"){tmp = http_request.uri;http_request.cgi = true;}else{}//拼接web根目录http_request.path += tmp;if(http_request.path.back() == '/'){http_request.path += "index.html";}//检查资源是否存在if(!stat(http_request.path.c_str(),&buf)){//检查资源是否是目录if(S_ISDIR(buf.st_mode)){http_request.path += "/";http_request.path += "index.html";stat(http_request.path.c_str(),&buf);}//检查资源是否是可自行文件 else if((S_IXUSR & buf.st_mode)||(S_IXGRP & buf.st_mode)||(S_IXOTH & buf.st_mode)){http_request.cgi = true;}http_request.size = buf.st_size;}else {LOG(INFO,http_request.path +"Resorce Is Not Exist");http_resbonse.status_code = NOT_FOUND;goto END;}if(http_request.cgi){http_resbonse.status_code = HandlerCgi();}else{http_resbonse.status_code = HandlerNonCgi();}
END:Build_HttpResbonseHelper();}int HandlerNonCgi(){auto& path = http_request.path;http_resbonse.fd = open(path.c_str(),O_RDONLY);if(http_resbonse.fd > 0){return OK;}return NOT_FOUND;}int HandlerCgi(){auto& bin = http_request.path;auto& query_get = http_request.query;auto& query_post = http_request.request_body;int upfd[2],downfd[2];if(pipe(upfd)<0 || pipe(downfd)<0){LOG(ERROR,"PIPE ERROR");return ERROR_SERVER;}pid_t pid = fork();if(pid == 0){close(upfd[0]);close(downfd[1]);dup2(downfd[0],0);dup2(upfd[1],1);std::string method = "METHOD=";method += http_request.method;putenv((char*)method.c_str()); if(http_request.method == "GET"){std::string query = "QUERY=";query += query_get;putenv((char*)query.c_str());}else if(http_request.method == "POST"){int cl = http_request.content_length;std::string content_length = "CONTENT_LENGTH=";content_length += std::to_string(cl);putenv((char*)content_length.c_str());}execl(bin.c_str(),bin.c_str(),nullptr);exit(1);}else if(pid > 0){close(upfd[1]);close(downfd[0]);std::string& method = http_request.method;if(method == "POST"){const char* query = query_post.c_str();ssize_t total = 0,size = 0;while(total < http_request.content_length && \(size = write(downfd[1],query+total,http_request.content_length - total)) > 0){total += size;}}std::string& body = http_resbonse.resbonse_body;char ch = 0;while(read(upfd[0],&ch,1) > 0){body.push_back(ch);}int status = 0;int ret = waitpid(pid,&status,0);if(ret == pid){if(WIFEXITED(status) && !WEXITSTATUS(status)){return OK;} else {LOG(ERROR,"----------");return ERROR_SERVER;}}close(upfd[0]);close(downfd[1]);}else{LOG(ERROR,"Create SonProcess Unsucess");return 404;}}void Build_HttpResbonseHelper(){int code = http_resbonse.status_code;auto& status_line = http_resbonse.resbonse_line;status_line = VERSION; status_line += " ";status_line += std::to_string(code);status_line += " ";status_line += StatusCodeDesc(code);status_line += LINE_END;if(code == 200){BuildOKResbonse();}else {BuildErrorResbonse(code);}}void BuildOKResbonse(){std::string line = "Content-Length: ";if(http_request.cgi){line += std::to_string(http_resbonse.resbonse_body.size());}else {line += std::to_string(http_request.size);}line+=LINE_END;http_resbonse.resbonse_header.push_back(line);line = "Content-Type: ";line += SuffixDesc(http_request.suffix);line += LINE_END;http_resbonse.resbonse_header.push_back(line);}void BuildErrorResbonse(int code){http_request.cgi = false;std::string page = GetErrorFile(code); std::cout<<"page"<<page<<std::endl;http_resbonse.fd = open(page.c_str(),O_RDONLY);if(http_resbonse.fd > 0){struct stat buf;stat(page.c_str(),&buf);http_request.size = buf.st_size;std::string line = "Content-type: text/html";line += LINE_END;http_resbonse.resbonse_header.push_back(line);line = "Content-Length: ";line += std::to_string(buf.st_size);line += LINE_END;http_resbonse.resbonse_header.push_back(line);}}void Send_HttpResbonse(){auto& line = http_resbonse.resbonse_line;send(sock,line.c_str(),line.size(),0);for(auto& item : http_resbonse.resbonse_header){send(sock,item.c_str(),item.size(),0);}send(sock,http_resbonse.blank.c_str(),http_resbonse.blank.size(),0);if(http_request.cgi){send(sock,http_resbonse.resbonse_body.c_str(),http_resbonse.resbonse_body.size(),0);}else {sendfile(sock,http_resbonse.fd,nullptr,http_request.size);close(http_resbonse.fd);}}~EndPoint(){close(sock);}
};
2.5 CGI技术
int HandlerCgi(){auto& bin = http_request.path;auto& query_get = http_request.query;auto& query_post = http_request.request_body;int upfd[2],downfd[2];if(pipe(upfd)<0 || pipe(downfd)<0){LOG(ERROR,"PIPE ERROR");return ERROR_SERVER;}pid_t pid = fork();if(pid == 0){ //子进程导入环境变量close(upfd[0]);close(downfd[1]);dup2(downfd[0],0);dup2(upfd[1],1);std::string method = "METHOD=";method += http_request.method;putenv((char*)method.c_str()); if(http_request.method == "GET"){std::string query = "QUERY=";query += query_get;putenv((char*)query.c_str());}else if(http_request.method == "POST"){int cl = http_request.content_length;std::string content_length = "CONTENT_LENGTH=";content_length += std::to_string(cl);putenv((char*)content_length.c_str());}execl(bin.c_str(),bin.c_str(),nullptr);exit(1);}else if(pid > 0){ //父进程写入数据 和 读取数据close(upfd[1]);close(downfd[0]);std::string& method = http_request.method;if(method == "POST"){const char* query = query_post.c_str();ssize_t total = 0,size = 0;while(total < http_request.content_length && \(size = write(downfd[1],query+total,http_request.content_length - total)) > 0){total += size;}}std::string& body = http_resbonse.resbonse_body;char ch = 0;while(read(upfd[0],&ch,1) > 0){body.push_back(ch);}int status = 0;int ret = waitpid(pid,&status,0);if(ret == pid){if(WIFEXITED(status) && !WEXITSTATUS(status)){return OK;} else {LOG(ERROR,"----------");return ERROR_SERVER;}}close(upfd[0]);close(downfd[1]);}else{LOG(ERROR,"Create SonProcess Unsucess");return 404;}}
test_cgi
#include <iostream>
#include <cstdlib>
#include <string>
#include <unistd.h>
bool GetQuery(std::string& query){std::string method = getenv("METHOD");if(method == "GET"){query = getenv("QUERY");}else if(method == "POST"){int content_length = atoi(getenv("CONTENT_LENGTH"));char ch = 0;while(content_length){ssize_t s = read(0,&ch,1);if(s>0){content_length--;query.push_back(ch);}else if(s == 0){break;}else{return false;}}}return true;
}void CutQuery(std::string& tar,std::string& key,std::string& value,const std::string& sep){size_t pos = tar.find(sep);if(pos != std::string::npos){key = tar.substr(0,pos);value = tar.substr(pos+sep.size());}
}int main(){std::string query;GetQuery(query);std::string str1,str2;std::string name1,name2;std::string value1,value2;CutQuery(query,str1,str2,"&");CutQuery(str1,name1,value1,"=");CutQuery(str2,name2,value2,"=");std::cout<<name1<<":"<<value1<<std::endl;std::cout<<name2<<":"<<value2<<std::endl;return 0;
}
2.5 线程池技术
#pragma once
#include <iostream>
#include "Task.hpp"
#include <pthread.h>
#include <queue>
#define NUM 10class ThreadPool{private:int num;std::queue<TASK> TaskQueue; pthread_mutex_t lock;pthread_cond_t cond;ThreadPool(int _num = NUM):num(_num){pthread_mutex_init(&lock,nullptr);pthread_cond_init(&cond,nullptr);}ThreadPool(const ThreadPool& TP){}~ThreadPool(){pthread_mutex_destroy(&lock);pthread_cond_destroy(&cond);}static ThreadPool* tp;public:static ThreadPool* GetInstance(int _num = NUM){static pthread_mutex_t t = PTHREAD_MUTEX_INITIALIZER;if(tp == nullptr){pthread_mutex_lock(&t);if(tp == nullptr){tp = new ThreadPool(_num);tp->InitThreadPool();}pthread_mutex_unlock(&t);}return tp;}static void* ThreadRoutine(void* arg){ThreadPool* tp = (ThreadPool*)arg;while(true){TASK task;tp->Lock();while(tp->IsEmpty()){tp->ThreadWait();}tp->PopTask(task);tp->Unlock();task.ProcessOn();}}bool InitThreadPool(){for(int i = 0; i< num;i++){pthread_t tid;if(0 != pthread_create(&tid,nullptr, ThreadRoutine,this)){LOG(FATAL,"create pthread unsucess");return false;}}return true;}void Lock(){pthread_mutex_lock(&lock);}void Unlock(){pthread_mutex_unlock(&lock);}void ThreadWait(){pthread_cond_wait(&cond,&lock);}void ThreadWakeup(){pthread_cond_signal(&cond);}bool IsEmpty(){return TaskQueue.size() == 0 ? true:false;}void PushTask(const TASK& task){Lock();TaskQueue.push(task);Unlock(); ThreadWakeup();//Routine函数中cond_wait用while循环判断主要是解锁和唤醒代码的顺序问题//如果先解锁,那么就会有其他进程抢到锁开始执行后续,但不一定是等待进程在执行//所以当后面唤醒等待进程时候,可能会发现任务队列仍然为空,但却继续往下执行,这不符合我们的逻辑}void PopTask(TASK& task){task = TaskQueue.front();TaskQueue.pop();}
};
ThreadPool* ThreadPool::tp = nullptr;3、项目总结
聚焦于处理HTTP的请求和构建对应响应; 我们主要研究基于 HTTP/1.0 短连接 的GET和POST方法;获得请求，分析请求，错误处理等; 制定特定的网页src用于返回; 引入简单的日志系统
搭建CGI机制;父子管道，设计dup2重定向，环境变量传参等
引入线程池;采用多线程技术，缓解内存开销.
 主体框架【pytorch】可运行版本)
)
