美文网首页物联网loT从业者物联网相关技术研究
ESP8266学习笔记(13)——HTTP服务器

ESP8266学习笔记(13)——HTTP服务器

作者: Leung_ManWah | 来源:发表于2019-08-15 15:34 被阅读4次

    一、背景

    首先手机APP连接智能插座热点(AP)将网关的SSID和密码通过HTTP协议配置到插座,完成配置后智能插座连接网关。

    Post请求和Get请求:

    二、流程

    2.1 定义相关变量及宏

    /*********************************************************************
     * LOCAL VARIABLES
     */
    static struct espconn s_httpSvrTcpEspconn;  // HTTP服务器TCP连接结构体
    
    /*********************************************************************
     * DEFINITIONS
     */
    #define URL_SIZE                    20
    #define REQUEST_DATA_SIZE           1024
    #define RESPONSE_DATA_SIZE          256
    
    #define GET     0
    #define POST    1
    
    #define HTTP_SERVER_RESPONSE_FRAME "HTTP/1.0 %s\r\n\
    Content-Length: %d\r\n\
    Server: lwIP/1.4.0\r\n\
    Content-type: application/json\r\n\
    Expires: Fri, 10 Apr 2008 14:00:00 GMT\r\n\
    Pragma: no-cache\r\n\r\n\
    %s"
    
    /*********************************************************************
     * TYPEDEFS
     */
    typedef struct urlFrame_t
    {
        uint8 type;
        char select[URL_SIZE];
        char command[URL_SIZE];
        char filename[URL_SIZE];
    } UrlFrame_t;
    

    2.2 初始化HTTP服务器

    /*********************************************************************
     * PUBLIC FUNCTIONS
     */
    /**
     @brief HTTP服务器初始化
     @param 无
     @return 无
    */
    void ICACHE_FLASH_ATTR
    HttpServerInit(void)
    {
        s_httpSvrTcpEspconn.type = ESPCONN_TCP;
        s_httpSvrTcpEspconn.state = ESPCONN_NONE;
        s_httpSvrTcpEspconn.proto.tcp = (esp_tcp *) os_zalloc(sizeof(esp_tcp));
        s_httpSvrTcpEspconn.proto.tcp->local_port = 80;
        espconn_regist_connectcb(&s_httpSvrTcpEspconn, connectCallback);
    
        espconn_accept(&s_httpSvrTcpEspconn);    // 开启监听
    }
    
    /*********************************************************************
     * LOCAL FUNCTIONS
     */
    /**
     @brief 连接成功的回调函数
     @param arg -[in] 指向传递给这个回调函数来使用的参数
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    connectCallback(void *arg)
    {
        struct espconn *pEspconn = arg;
    
        espconn_regist_recvcb(pEspconn, receiveDataCallback);
        espconn_regist_disconcb(pEspconn, disconnectCallback);
    }
    
    /**
     @brief 接收数据的回调函数
     @param arg -[in] 指向传递给这个回调函数来使用的参数
     @param pData -[in] 接收的数据
     @param len -[in] 接收的数据长度
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    receiveDataCallback(void *arg, char *pData, unsigned short len)
    {
        if(checkDataIntegrity(pData, len) == false)
        {
            return ;
        }
        os_printf("recvData:  %s\n", pData);
    
        UrlFrame_t urlFrame;
        char requestData[REQUEST_DATA_SIZE] = {0};
    
        findRequestData(pData, requestData);
        parseUrl(pData, &urlFrame);
    
        switch(urlFrame.type)
        {
        case GET:
            os_printf("We have a GET request.\n");
            handleGetUrlPath(&urlFrame, requestData);
            break;
        case POST:
            os_printf("We have a POST request.\n");
            handlePostUrlPath(&urlFrame, requestData);
            break;
        default:
            break;
        }
    }
    
    /**
     @brief 断连的回调函数
     @param arg -[in] 指向传递给这个回调函数来使用的参数
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    disconnectCallback(void *arg)
    {
        struct espconn *pEspconn = arg;
    
        os_printf("httpserver's %d.%d.%d.%d:%d disconnect\n",
                    pEspconn->proto.tcp->remote_ip[0], pEspconn->proto.tcp->remote_ip[1],
                    pEspconn->proto.tcp->remote_ip[2], pEspconn->proto.tcp->remote_ip[3],
                    pEspconn->proto.tcp->remote_port);
    }
    

    2.3 处理接收数据

    2.3.1 检查数据完整性

    /**
     @brief 检查数据完整性
     @param pRecvData -[in] 接收的数据
     @param recvDatalen -[in] 接收的数据长度
     @return 1 - 数据完整;0 - 数据缺失
    */
    static bool ICACHE_FLASH_ATTR
    checkDataIntegrity(char *pRecvData, uint16 recvDatalen)
    {
        if(!pRecvData)
        {
            return false;
        }
    
        char lenBuffer[10] = {0};
        char *pTemp = NULL;
        char *pData = NULL;
        char *pTempRecvData;
        uint16 tempLen = recvDatalen;
        uint32 tempTotalLen = 0;
        uint32 dataSumLen = 0;
    
        pTemp = (char *) os_strstr(pRecvData, "\r\n\r\n");
    
        if(pTemp != NULL)
        {
            tempLen -= pTemp - pRecvData;
            tempLen -= 4;
            tempTotalLen += tempLen;
    
            pData = (char *) os_strstr(pRecvData, "Content-Length: ");
    
            if(pData != NULL)
            {
                pData += 16;
                pTempRecvData = (char *) os_strstr(pData, "\r\n");
    
                if(pTempRecvData != NULL)
                {
                    os_memcpy(lenBuffer, pData, pTempRecvData - pData);
                    dataSumLen = atoi(lenBuffer);
                    os_printf("A_dat:%u,total:%u,lenght:%u\n",dataSumLen, tempTotalLen, tempLen);
    
                    if(dataSumLen != tempTotalLen)
                    {
                        return false;
                    }
    
                    return true;
                }
            }
            else
            {
                return true;
            }
        }
    
        return false;
    }
    

    2.3.2 查找请求数据

    /**
     @brief 查找请求数据
     @param pRecvData -[in] 接收的数据
     @param pRequestData -[in&out] 请求的数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    findRequestData(char *pRecvData, char *pRequestData)
    {
        char *pRequestDataStart = NULL;
        char *pRequestDataEnd = NULL;
    
        pRequestDataStart = strchr(pRecvData, '{');
        if(pRequestDataStart != NULL)
        {
            pRequestDataEnd = strrchr(pRecvData, '}');
            if(pRequestDataEnd != NULL)
            {
                os_memcpy(pRequestData, pRequestDataStart, pRequestDataEnd - pRequestDataStart + 1);
            }
        }
    
        pRequestData[pRequestDataEnd - pRequestDataStart + 1] = '\0';
    }
    

    2.3.3 解析URL

    /**
     @brief 解析URL
     @param pRecvData -[in] 接收的数据
     @param pUrlFrame -[in&out] URL框架
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    parseUrl(char *pRecvData, UrlFrame_t *pUrlFrame)
    {
        if(pUrlFrame == NULL || pRecvData == NULL)
        {
            return ;
        }
    
        char *pStr = NULL;
        uint8 length = 0;
        char *pBuffer = NULL;
        char *pBuf = NULL;
    
        pBuffer = (char *) os_strstr(pRecvData, "Host:");
    
        if(pBuffer != NULL)
        {
            length = pBuffer - pRecvData;
            pBuf = (char *)os_zalloc(length + 1);
            pBuffer = pBuf;
            os_memcpy(pBuffer, pRecvData, length);
            os_memset(pUrlFrame->select, 0, URL_SIZE);
            os_memset(pUrlFrame->command, 0, URL_SIZE);
            os_memset(pUrlFrame->filename, 0, URL_SIZE);
    
            if(os_strncmp(pBuffer, "GET ", 4) == 0)
            {
                pUrlFrame->type = GET;
                pBuffer += 4;
            }
            else if(os_strncmp(pBuffer, "POST ", 5) == 0)
            {
                pUrlFrame->type = POST;
                pBuffer += 5;
            }
    
            pBuffer++;
            pStr = (char *) os_strstr(pBuffer, "?");
    
            if(pStr != NULL)
            {
                length = pStr - pBuffer;
                os_memcpy(pUrlFrame->select, pBuffer, length);
                pStr++;
                pBuffer = (char *) os_strstr(pStr, "=");
    
                if(pBuffer != NULL)
                {
                    length = pBuffer - pStr;
                    os_memcpy(pUrlFrame->command, pStr, length);
                    pBuffer++;
                    pStr = (char *) os_strstr(pBuffer, "&");
    
                    if(pStr != NULL)
                    {
                        length = pStr - pBuffer;
                        os_memcpy(pUrlFrame->filename, pBuffer, length);
                    }
                    else
                    {
                        pStr = (char *) os_strstr(pBuffer, " HTTP");
    
                        if(pStr != NULL)
                        {
                            length = pStr - pBuffer;
                            os_memcpy(pUrlFrame->filename, pBuffer, length);
                        }
                    }
                }
            }
    
            os_free(pBuf);
        }
    }
    

    2.3.4 解析GET请求URL

    cJSON使用查看 ESP8266学习笔记(8)——第三方库cJSON使用

    以查询继电器状态为例
    HTTP Header中
    GET /config?command=switch HTTP/1.1

    /**
     @brief 处理GET请求URL路径
     @param pUrlFrame -[in] URL框架
     @param pRequestData -[in] 请求的数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    handleGetUrlPath(UrlFrame_t *pUrlFrame, char *pRequestData)
    {
        os_printf("Type:%d, Select:%s, Command:%s, Filename:%s ",
        pUrlFrame->type, pUrlFrame->select, pUrlFrame->command, pUrlFrame->filename);
        if(os_strcmp(pUrlFrame->select, "config") == 0)
        {
            if(os_strcmp(pUrlFrame->command, "command") == 0)
            {
                if(os_strcmp(pUrlFrame->filename, "switch") == 0)
                {
                    sendRelayStatusResponse();
                }
            }
        }
    }
    

    2.3.4.1 封装继电器状态响应包

    /**
     @brief 发送继电器状态响应
     @param pRequestData -[in] 请求的数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    sendRelayStatusResponse(void)
    {
        char sendData[RESPONSE_DATA_SIZE] = {0};
        jsonPackageRelayStatusData(true, sendData);
        sendGetResponse(true, sendData);
    }
    
    /**
     @brief JSON格式封装继电器状态数据
     @param responseOk -[in] 响应是否成功
     @param pSendData -[in&out] 要封装的发送数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    jsonPackageRelayStatusData(bool responseOk, char *pSendData)
    {
        if(!pSendData)
        {
            return ;
        }
    
        cJSON *pRoot = cJSON_CreateObject();
    
        uint16 statusCode;
    
        if(responseOk)
        {
            statusCode = 200;
        }
        else
        {
            statusCode = 400;
        }
    
        cJSON_AddNumberToObject(pRoot, "status", statusCode);
        cJSON_AddNumberToObject(pRoot, "switch", GetRelayStatus()); // 加入自己的获取继电器状态函数
        char *tempBuffer = cJSON_Print(pRoot);
        os_sprintf(pSendData, "%s", tempBuffer);
    
        os_free((void *) tempBuffer);
        cJSON_Delete(pRoot);
    }
    

    2.3.4.2 发送继电器状态响应包

    /**
     @brief 发送GET请求HTTP响应
     @param responseOk -[in] 响应是否成功
     @param pResponseData -[in] 响应数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    sendGetResponse(bool responseOk, char *pResponseData)
    {
        char sendData[RESPONSE_DATA_SIZE] = {0};
        char responseCode[15] = {0};
    
        if(responseOk)
        {
            os_sprintf(responseCode, "200 OK", os_strlen(responseCode));
        }
        else
        {
            os_sprintf(responseCode, "400 BadRequest", os_strlen(responseCode));
        }
    
        os_sprintf(sendData, HTTP_SERVER_RESPONSE_FRAME, responseCode, os_strlen(pResponseData), pResponseData);
    
        espconn_sent(&s_httpSvrTcpEspconn, sendData, os_strlen(sendData));
    }
    

    2.3.5 解析POST请求URL

    cJSON使用查看 ESP8266学习笔记(8)——第三方库cJSON使用
    以设置继电器状态为例
    HTTP Header中
    POST /config?command=switch HTTP/1.1

    /**
     @brief 处理POST请求URL路径
     @param pUrlFrame -[in] URL框架
     @param pRequestData -[in] 请求的数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    handlePostUrlPath(UrlFrame_t *pUrlFrame, char *pRequestData)
    {
        os_printf("Type:%d, Select:%s, Command:%s, Filename:%s ",
        pUrlFrame->type, pUrlFrame->select, pUrlFrame->command, pUrlFrame->filename);
    
        if(os_strcmp(pUrlFrame->select, "config") == 0)
        {
            if(os_strcmp(pUrlFrame->command, "command") == 0)
            {
                if(os_strcmp(pUrlFrame->filename, "switch") == 0)
                {
                    configRelayStatus(pRequestData);
                }
            }
        }
    }
    

    2.3.5.1 解析设置继电器状态

    /**
     @brief 配置继电器开关接口
     @param pRequestData -[in] 请求的数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    configRelayStatus(char *pRequestData)
    {
        if(!pRequestData)
        {
            return ;
        }
    
        cJSON *pRoot = cJSON_Parse(pRequestData);
        if(!pRoot)
        {
            return ;
        }
    
        char sendData[RESPONSE_DATA_SIZE] = {0};
        cJSON *pRequest = cJSON_GetObjectItem(pRoot, "request");                        // 解析request字段内容
        if(!pRequest)
        {
            os_sprintf(sendData, "%s", "No request Item");
            sendPostResponse(false, sendData);
            cJSON_Delete(pRoot);
            return ;
        }
    
        cJSON *pStatus = cJSON_GetObjectItem(pRequest, "status");                       // 解析request子节点status字段内容
        if(!pStatus)
        {
            os_sprintf(sendData, "%s", "No status Item");
            sendPostResponse(false, sendData);
            cJSON_Delete(pRoot);
            return ;
        }
    
        uint8 relayStatus = pStatus->valueint;
        SetRelayStatus(relayStatus);      // 加入自己设置继电器状态函数                                              // 设置继电器状态
    
        os_sprintf(sendData, "%s", "Config switch succeed");
        sendPostResponse(true, sendData);
        cJSON_Delete(pRoot);
    }
    

    2.3.5.2 发送响应包

    /**
     @brief 发送POST请求的HTTP响应
     @param responseOk -[in] 响应是否成功
     @param pResponseData -[in] 响应数据
     @return 无
    */
    static void ICACHE_FLASH_ATTR
    sendPostResponse(bool responseOk, char *pResponseData)
    {
        char sendData[RESPONSE_DATA_SIZE] = {0};
        char responseCode[15] = {0};
    
        jsonPackageResponseData(responseOk, pResponseData);
    
        if(responseOk)
        {
            os_sprintf(responseCode, "200 OK", os_strlen(responseCode));
        }
        else
        {
            os_sprintf(responseCode, "400 BadRequest", os_strlen(responseCode));
        }
    
        os_sprintf(sendData, HTTP_SERVER_RESPONSE_FRAME, responseCode, os_strlen(pResponseData), pResponseData);
    
        espconn_sent(&s_httpSvrTcpEspconn, sendData, os_strlen(sendData));
    }
    

    三、使用方法


    • 由 Leung 写于 2019 年 8 月 15 日

    相关文章

      网友评论

        本文标题:ESP8266学习笔记(13)——HTTP服务器

        本文链接:https://www.haomeiwen.com/subject/usgajctx.html