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