http发送和接收图片json文件

 一、http数据发送

1、先将图片转换为base64格式

std::string detectNet::Mat2Base64(const cv::Mat &image, std::string imgType){std::vector<uchar> buf;cv::imencode(imgType, image, buf);//uchar *enc_msg = reinterpret_cast<unsigned char*>(buf.data());std::string img_data = base64_encode(buf.data(), buf.size(), false);return img_data;
}

2、将数据以json格式进行发送

void detectNet::send_json_people(cv::Mat img, std::string label, std::string level, std::string rtsp){std::string out = Mat2Base64(img,".jpg");//std::cout << out << std::endl;ImgInfo imgInfo(out, label, level, rtsp);static auto client = httplib::Client("127.0.0.1", 18080);auto result = client.Post("/uploadAlgorithmResult", imgInfo.to_json_people(), "application/json");if (result != nullptr && result->status == 200) {std::cout << result->body << std::endl;}
}

其中 ImgInfo 类为：

#ifndef HTTP_DEMO_IMGINFO_H
#define HTTP_DEMO_IMGINFO_H#include <utility>#include "cJSON.h"
#include "base64.h"#define RTSP_URL "rtsp://admin:a123456789@192.168.8.31:554/h264/ch1/main/av_stream/1"
#define AlgorithmType "hook_detection"
#define AlgorithmType_people "danger_zone"
#define AlgorithmType_crooked "crooked"class ImgInfo {
private:std::string img;std::string label;std::string rtsp;std::string level;
public:ImgInfo(std::string img, std::string label, std::string level, std::string rtsp) : img(std::move(img)), label(std::move(label)),level(std::move(level)), rtsp(std::move(rtsp)) {}std::string to_json_people() {auto *root = cJSON_CreateObject();cJSON_AddStringToObject(root, "image", img.c_str());cJSON_AddStringToObject(root, "level", level.c_str());cJSON_AddStringToObject(root, "rtsp", rtsp.c_str());cJSON_AddStringToObject(root, "type", AlgorithmType_people);cJSON_AddStringToObject(root, "label", label.c_str());/*cJSON *label_array = cJSON_CreateArray();for (auto &i: label) {cJSON_AddItemToArray(label_array, cJSON_CreateString(i.c_str()));}cJSON_AddItemToObject(root, "label", label_array);*/char *out = cJSON_Print(root);std::string res = out;free(out);cJSON_Delete(root);return res;}
};#endif //HTTP_DEMO_IMGINFO_H

上述代码中json数据有五个部分：image为图片数据，level是告警等级，rtsp为数据流地址，type是算法类型，label是算法标签等，所以数据发送为这五个内容。

二、http数据接收

HttpServer.cpp如下： 

//#include <QFile>
//#include <FileUtils.hpp>
#include "HttpServer.h"
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
//#include "QString"
//#include "TimeUtils.hpp"
//#include "AlgorithmCommon.h"
//#include "QJsonObject"
//#include "QJsonDocument"
//#include "QJsonArray"
//#include "httplib.h"//#include "log.h"
//#include "cJSON.h"HttpServer::HttpServer(std::string ip, int port) : server_ip(ip), server_port(port) {//event_handler = new AlgorithmAlarmHandler();}HttpServer::~HttpServer() {stopListen();if (read_thd.joinable()) {read_thd.join();}
}void HttpServer::startListen() {read_thd = std::thread([=]() {serverListen();});//event_handler->startHandlerThread();
}void HttpServer::stopListen() {if (server.is_running()) {server.stop();}
}void HttpServer::serverListen() {if (!server.is_valid()) {std::cout << "http server invalid" << std::endl;return;}// 服务器状态server.Get("/server/status", [&](const Request &req, Response &res) {onServerStatus(req, res);});// 上传算法结果server.Post("/uploadAlgorithmResult", [&](const Request &req, Response &res) {onUploadAlgorithmResult(req, res);});// 错误处理server.set_error_handler([&](const Request &req, Response &res) {onErrorHandle(req, res);});//qDebug() << "server start listen";server.listen(server_ip.c_str(), server_port);
}void HttpServer::onServerStatus(const httplib::Request &req, httplib::Response &res) {res.body = R"({"code": 200,"msg": "Server is already Running"})";
}void HttpServer::onUploadAlgorithmResult(const httplib::Request &req, httplib::Response &res) {std::string content_type = httputillib::GetContentType(req.headers);//if (content_type != "application/json") {//     qDebug() << "contentType 异常, content_type:" << QString::fromStdString(content_type);//}bool parseRet = parseAlgorithmResult(req.body);//bool parseRet = true;std::string rspMsg;if (parseRet) {rspMsg = std::string(R"({"msg":"Recv Success, Parse Success."})");} else {rspMsg = std::string(R"({"msg":"Recv Success, Parse Failed."})");}res.body = std::move(rspMsg);
}// 错误请求处理
void HttpServer::onErrorHandle(const httplib::Request &req, httplib::Response &res) {const char *fmt = {"\"error\": \"服务器不支持该方法\""};char buf[BUFSIZ] = {0};snprintf(buf, sizeof(buf), fmt, res.status);res.set_content(buf, "application/json");
}bool HttpServer::parseAlgorithmResult(const std::string &body) {//std::cout << "body:" << body << std::endl;Json::Reader reader;Json::Value root;//std::ifstream in(body, std::ios::binary);//if (!in.is_open()) {//    std::cout << "open file failed" << std::endl;//    return false;//}if (!reader.parse(body, root)) {std::cout << "parse failed" << std::endl;return false;}std::string rtsp = root["rtsp"].asString();std::cout << "rtsp:" << rtsp << std::endl;std::string level = root["level"].asString();std::cout << "level:" << level << std::endl;std::string type = root["type"].asString();std::cout << "type:" << type << std::endl;std::string image = root["image"].asString();//std::cout << "image:" << image << std::endl;std::string out = base64_decode(image);std::string decoded_jpeg = std::move(out);//std::cout << "decoded_jpeg: " << decoded_jpeg << std::endl;cv::Mat mat2(1, decoded_jpeg.size(), CV_8U, (char*)decoded_jpeg.data());cv::Mat dst = cv::imdecode(mat2, CV_LOAD_IMAGE_COLOR);cv::imwrite(rtsp.substr(1) + ".jpg", dst);  return true;
}

 HttpServer.h如下：

//#ifndef CPPHTTPSERVER_HTTPSERVER_H
//#define CPPHTTPSERVER_HTTPSERVER_H#include "httputillib.h"
#include "httplib.h"
#include "base64.h"
//#include "thread"
#include <thread>
#include <time.h>#include <json.h>class HttpServer{
public:HttpServer(std::string ip, int port);~HttpServer();void startListen();void stopListen();private:void serverListen();// 回调函数: 错误请求处理void onErrorHandle(const httplib::Request &req, httplib::Response &res);// 回调函数: 获取服务器状态void onServerStatus(const httplib::Request &req, httplib::Response &res);// 回调函数: 上传算法结果void onUploadAlgorithmResult(const httplib::Request &req, httplib::Response &res);// 回调函数：处理算法数据bool parseAlgorithmResult(const std::string &body);std::string server_ip;int server_port;Server server;std::thread read_thd;};//#endif //CPPHTTPLIB_HTTPLIB_H

httputillib.h如下：

#include <httplib.h>using namespace httplib;namespace httputillib {
// 打印请求头
static std::string DumpHeaders(const Headers &headers) {std::string s;char buf[BUFSIZ] = {0};for (auto it = headers.begin(); it != headers.end(); ++it) {const auto &x = *it;snprintf(buf, sizeof(buf), "%s: %s\n", x.first.c_str(), x.second.c_str());s += buf;}return s;
}// 从请求同获取content type
static std::string GetContentType(const httplib::Headers &headers) {auto iter = headers.find("Content-Type");if (iter == headers.end()) {return std::string();}return iter->second;
}};

上述完整代码可详见github或者百度网盘