编写一个基于命令行的获取天气预报的程序。（云市场天气API、HTTP、JSON ）

爱被打了一巴掌 2022-12-05 13:55 174阅读 0赞

更多资料请点击：[我的目录][Link 1]  
本篇仅用于记录自己所学知识及应用，代码仍可优化，仅供参考，如果发现有错误的地方，尽管留言于我，谢谢。  
[快递信息查询][Link 2]

运行效果：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center]

main函数：

#include <stdio.h>
    #include <unistd.h>
    #include <stdlib.h>
    #include <arpa/inet.h>
    #include <sys/socket.h>
    #include <netdb.h>
    #include <string.h>
    #include "cJSON.h"
    
    char *httpRequest()
    { 
        static char request[1024];
        printf("请求获取信息！\n\n");
        snprintf(request, 1024, "GET /spot-to-weather?area=广州 HTTP/1.1\r\n"
                                "Host:weather01.market.alicloudapi.com\r\n"
                                "Authorization:APPCODE 8b75a704109c40089f49902b2fa745\r\n"
                                "\r\n");
        return request;
    }
    
    int main()
    { 
        struct hostent *he = gethostbyname("weather01.market.alicloudapi.com");
        if(he == NULL)
        { 
            perror("DNS解析失败");
            exit(0);
        }
        printf("IP:%s\n", inet_ntoa(*((struct in_addr *)(he->h_addr_list)[0])));
        char buf[20] = { 0};
        sprintf(buf,"%s",inet_ntoa(*((struct in_addr *)(he->h_addr_list)[0])));
    
        struct sockaddr_in bindaddr;                                                    //定义ipv4地址结构体变量
        bzero(&bindaddr,sizeof(bindaddr));
        bindaddr.sin_family=AF_INET;
        bindaddr.sin_addr.s_addr=inet_addr("192.168.1.157");                            //绑定客户端自己的ip地址
        bindaddr.sin_port=htons(10000);                                                 //绑定客户端自己的端口号
    
        struct sockaddr_in serveraddr;                                                  //定义结构体变量存放对方(服务器)的ip和端口号
        bzero(&serveraddr,sizeof(serveraddr));
        serveraddr.sin_family=AF_INET;
        serveraddr.sin_addr.s_addr=inet_addr(buf);                                      //服务器的ip地址
        serveraddr.sin_port=htons(80);                                                  //服务器的端口号
    
        int tcpsock=socket(AF_INET,SOCK_STREAM,0);                                      //创建tcp套接字
        if(tcpsock==-1)
        { 
            perror("创建tcp套接字!\n");
            return -1;
        }
    
        int on=1;
        setsockopt(tcpsock,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(on));                     //设置端口释放后立即就可以被再次使用
    
        int ret=bind(tcpsock,(struct sockaddr *)&bindaddr,sizeof(bindaddr));            //绑定ip和端口号
        if(ret==-1)
        { 
            perror("绑定失败！\n");
            return -1;
        }
    
        ret=connect(tcpsock,(struct sockaddr *)&serveraddr,sizeof(serveraddr));         //连接服务器
        if(ret==-1)
        { 
            perror("连接服务器失败！\n");
            return -1;
        }
        else
        { 
            printf("链接成功！\n");
        }
    
        char *s = httpRequest();
        write(tcpsock, s, strlen(s));
    
        // 接收服务器的 HTTP 响应
        char *response = calloc(100, 1024);
        int total = 0;
        while(1)
        { 
            if(total > 100*1024)
            { 
                printf("响应数据超过100k，请重新分配内存\n");
                break;
            }
    
            int n = read(tcpsock, response+total, 10*1024);
            if(n <= 0)
                break;
    
            total += n;
        }
    
        //printf("响应报文:%s", response);
    
        char *sbuf = calloc(100, 1024);
        strtok(response,"{");                                                           //以第一个大括号分割
        sprintf(sbuf,"{%s",strtok(NULL,"\0"));                                          //补回被分割的{ 
        //printf("JSON数据：%s", sbuf); //通过https://www.bejson.com/jsonviewernew/查看JSON视图
    
        cJSON* root = cJSON_Parse(sbuf);                                                //从给定的json字符串中得到cjson对象，（root即为根目录）
        cJSON* root_body = cJSON_GetObjectItem(root, "showapi_res_body");               //根据键获取对应的值（cjson对象）,（root_body即为root的下一级目录）
        cJSON* root_body_city_info = cJSON_GetObjectItem(root_body, "cityInfo");        //根据键获取对应的值（cjson对象）
        cJSON* root_body_day1 = cJSON_GetObjectItem(root_body, "f1");                   //根据键获取对应的值（cjson对象），（root_body_day1即为root_body的下一级目录）
    
        printf("城市: %s\n",cJSON_GetObjectItem(root_body_city_info, "c5")->valuestring);
    
        cJSON* root_body_d1w1 = cJSON_GetObjectItem(root_body_day1, "day");
        printf("日期: %s\n",root_body_d1w1->valuestring);
    
        cJSON* root_body_d1w2 = cJSON_GetObjectItem(root_body_day1, "day_weather");
        printf("日间天气: %s\n",root_body_d1w2->valuestring);
    
        cJSON* root_body_d1w3 = cJSON_GetObjectItem(root_body_day1, "night_weather");
        printf("夜间天气: %s\n",root_body_d1w3->valuestring);
    
        cJSON* root_body_d1w4 = cJSON_GetObjectItem(root_body_day1, "day_air_temperature");
        printf("日间温度: %s\n",root_body_d1w4->valuestring);
    
        cJSON* root_body_d1w5 = cJSON_GetObjectItem(root_body_day1, "night_air_temperature");
        printf("夜间温度: %s\n\n",root_body_d1w5->valuestring);
    
        printf("城市: %s\n",cJSON_GetObjectItem(root_body_city_info, "c5")->valuestring);
    
        cJSON* root_body_day2 = cJSON_GetObjectItem(root_body, "f2");
        cJSON* root_body_d2w1 = cJSON_GetObjectItem(root_body_day2, "day");
        printf("日期: %s\n",root_body_d2w1->valuestring);
    
        cJSON* root_body_d2w2 = cJSON_GetObjectItem(root_body_day2, "day_weather");
        printf("日间天气: %s\n",root_body_d2w2->valuestring);
    
        cJSON* root_body_d2w3 = cJSON_GetObjectItem(root_body_day2, "night_weather");
        printf("夜间天气: %s\n",root_body_d2w3->valuestring);
    
        cJSON* root_body_d2w4 = cJSON_GetObjectItem(root_body_day2, "day_air_temperature");
        printf("日间温度: %s\n",root_body_d2w4->valuestring);
    
        cJSON* root_body_d2w5 = cJSON_GetObjectItem(root_body_day2, "night_air_temperature");
        printf("夜间温度: %s\n\n",root_body_d2w5->valuestring);
    
        printf("城市: %s\n",cJSON_GetObjectItem(root_body_city_info, "c5")->valuestring);
    
        cJSON* root_body_day3 = cJSON_GetObjectItem(root_body, "f3");
        cJSON* root_body_d3w1 = cJSON_GetObjectItem(root_body_day3, "day");
        printf("日期: %s\n",root_body_d3w1->valuestring);
    
        cJSON* root_body_d3w2 = cJSON_GetObjectItem(root_body_day3, "day_weather");
        printf("日间天气: %s\n",root_body_d3w2->valuestring);
    
        cJSON* root_body_d3w3 = cJSON_GetObjectItem(root_body_day3, "night_weather");
        printf("夜间天气: %s\n",root_body_d3w3->valuestring);
    
        cJSON* root_body_d3w4 = cJSON_GetObjectItem(root_body_day3, "day_air_temperature");
        printf("日间温度: %s\n",root_body_d3w4->valuestring);
    
        cJSON* root_body_d3w5 = cJSON_GetObjectItem(root_body_day3, "night_air_temperature");
        printf("夜间温度: %s\n\n",root_body_d3w5->valuestring);
    
        cJSON_Delete(root);                                                           //将json结构占用的数据空间释放
    
        return 0;
    }

cJSON部分：

链接：https://pan.baidu.com/s/1zLebKOF7NHqF7f8Spl7G_Q 
    提取码：2u0j

解压后将文件放在main.c同目录下：

终端编译指令：  gcc main.c cJSON.c -L cJSON.h
    终端运行指令： ./a.out

其中request的信息需要对应下图红框内容：

char *httpRequest()
    { 
        static char request[1024];
        printf("请求获取信息！\n\n");
        snprintf(request, 1024, "GET /spot-to-weather?area=广州 HTTP/1.1\r\n"
                                "Host:weather01.market.alicloudapi.com\r\n"
                                "Authorization:APPCODE 8b75a70400042069f49902b27af45\r\n"
                                "\r\n");
        return request;
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center 1]

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center 2]

cJSON的用法：[https://www.cnblogs.com/catgatp/p/6379955.html][https_www.cnblogs.com_catgatp_p_6379955.html]

[Link 1]: http://note.youdao.com/noteshare?id=1370b0e8f4a16b80e7dede7836df3c08
[Link 2]: https://blog.csdn.net/weixin_43793181/article/details/108522822
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center]: /images/20221123/a36a50031f2346d08eb5950381cffc7e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221123/ae8d71be6c3c447b97b5d89a02bbf84f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70_pic_center 2]: /images/20221123/00349e5361c04fb188e995754eab37ae.png
[https_www.cnblogs.com_catgatp_p_6379955.html]: https://www.cnblogs.com/catgatp/p/6379955.html