1、准备开发板

开发板功能区分布图

在这里插入图片描述

开发板俯视图

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2、HTTP协议介绍

HTTP协议简介

    HTTP(HyperText Transfer Protocol)协议,即超文本传输协议,是一种用于分布式、协作式和超媒体信息系统的应用层协议。HTTP 协议是基于 TCP/IP 协议的网络应用层协议。
    HTTP是一个客户端终端(用户)和服务器端(网站)请求和应答的标准(TCP)。通过使用网页浏览器、网络爬虫或者其它的工具,客户端发起一个HTTP请求到服务器上指定端口(默认端口为80)。服务器接收到请求之后,通过接收到的信息判断响应方式,并且给予客户端相应的响应,完成整个 HTTP 数据交互流程。

HTTP 工作原理

HTTP 请求/响应的步骤
1. 客户端连接到Web服务器一个HTTP客户端,通常是浏览器,与Web服务器的HTTP端口(默认为80)建立一个TCP套接字连接。
2. 发送HTTP请求通过TCP套接字,客户端向Web服务器发送一个文本的请求报文,一个请求报文由请求行、请求头部、空行和数据包4部分组成。
3. 服务器接受请求并返回HTTP响应Web服务器解析请求,定位请求资源。服务器将资源复本写到TCP套接字,由客户端读取。一个响应由状态行、响应头部、空行和响应数据4部分组成。
4. 释放连接TCP连接若connection 模式为close,则服务器主动关闭TCP连接,客户端被动关闭连接,释放TCP连接;若connection 模式为keepalive,则该连接会保持一段时间,在该时间内可以继续接收请求;
5. 客户端浏览器解析HTML内容客户端浏览器首先解析状态行,查看表明请求是否成功的状态代码。然后解析每一个响应头,响应头告知以下为若干字节的HTML文档和文档的字符集。客户端浏览器读取响应数据HTML,根据HTML的语法对其进行格式化,并在浏览器窗口中显示。

HTTP协议请求头Request Headers

客户端发送一个HTTP请求到服务器的请求头主要包括:请求行、请求头部、空行、数据包
如下图是一个 POST 请求的信息:
在这里插入图片描述

HTTP 协议响应信息 Response

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HTTP 协议状态码

状态代码类别原因短语
1xxInfomational(信息性状态码)接收的请求正在处理
2xxSuccess(成功状态码)请求正常处理完毕
3xxRedirection(重定向状态码)需要进行附加操作以完成请求
4xxClient Error(客户端错误状态码)服务器无法处理请求
5xxServer Error(服务器错误状态码)服务器处理请求出错

3、在MDK中编写代码

WebClient客户端代码
web_strdup将字符串复制到新开辟的内存空间
webclient_session_create创建webclient客户端
webclient_header_fields_add将请求句柄封装到客户端缓存区
webclient_header_fields_get解析响应数据的单一消息报头
webclient_header_length_response获取请求头的长度
webclient_handle_response获取服务器响应的状态码
webclient_data_analysis获取服务器返回的数据包
HTTP请求方法
webclient_get_method客户端GET请求方法
webclient_post_method客户端POST请求方法

修改ESP8266.c代码中的NET_DEVICE_LinkServer_Init函数(代码在上一章)

ESP8266_RETTYPE NET_DEVICE_LinkServer_Init(void)
{
	
	unsigned char errCount = 0, errType = 0;
	char cfgBuffer[70];
	
	switch(netDeviceInfo.initStep)
	{
		case 0:
			if(ESP8266_Net_Mode_Choose(STA) == ESP8266_OK)
				netDeviceInfo.initStep++;
			break;
		case 1:
			if(ESP8266_Enable_MultipleId(DISABLE) == ESP8266_OK)
				netDeviceInfo.initStep++;
			break;
		case 2:
			if(ESP8266_JoinAP(netDeviceInfo.staName,netDeviceInfo.staPass) == ESP8266_OK)
				netDeviceInfo.initStep++;
			break;
		case 3:
			//注释掉这一行,因为请求的网址不同
//			if(ESP8266_Link_Server(enumTCP,netDeviceInfo.staIPAddress,netDeviceInfo.staPort,Single_ID_0) == ESP8266_OK)
				netDeviceInfo.initStep++;
			break;
		default:
			 netDeviceInfo.netWork = 1;
			 errType = 3;
			break;
	}
	
	
		return errType;
	
}

在webclient.h中编写以下代码

#ifndef __WEBCLIENT_H_
#define __WEBCLIENT_H_
#include "sys.h"


#ifndef WEBCLIENT_OK
#define WEBCLIENT_OK 0
#endif

#ifndef WEBCLIENT_NOK
#define WEBCLIENT_NOK 1
#endif

typedef struct __webclient_header
{
    char* buffer;

    unsigned int length;                      /* content header buffer size */

    unsigned int size;                        /* maximum support header size */
}webclient_header;

typedef struct __webclient_session
{	
	webclient_header* header;    /* webclient response header information */
	
	int resp_status;
	int content_length;
}webclient_session;


void webclient_get_method(void);
void webclient_post_method(void);

#endif

在webclient.c中编写以下代码

#include "webclient.h"
#include "ESP8266.h"
#include "usart.h"
#include "StringUtil.h"


//将字符串复制到新开辟的内存空间
char* web_strdup(const char* s)
{
	uint16_t len = strlen(s) + 1;
	char* tmp = (char*)malloc(len);

	if (!tmp)
			return NULL;

	memcpy(tmp, s, len);

	return tmp;
}

//创建webclient客户端
webclient_session* webclient_session_create(uint16_t header_sz)
{
	webclient_session* session;
	/* create session */
	session = (webclient_session*)calloc(1, sizeof(webclient_session));
	if (session == NULL)
	{
			printf("webclient create failed, no memory for webclient session!");
			return NULL;
	}
	/* initialize the socket of session */
	session->content_length = -1;
	session->header = (webclient_header*)calloc(1, sizeof(webclient_header));
	if (session->header == NULL)
	{
			printf("webclient create failed, no memory for session header buffer!");
			free(session->header);
			free(session);
			session = NULL;
			return NULL;
	}

	session->header->size = header_sz;
	session->header->buffer = (char*)calloc(1, header_sz);
	if (session->header->buffer == NULL)
	{
			printf("webclient create failed, no memory for session header buffer!");
			free(session->header);
			free(session);
			session = NULL;
			return NULL;
	}

	return session;
}

//将请求句柄封装到客户端缓存区
unsigned char webclient_header_fields_add(webclient_session* session, const char* fmt, ...)
{
	int length;
	va_list args;
	va_start(args, fmt);
	length = vsnprintf(session->header->buffer + session->header->length, session->header->size - session->header->length, fmt, args);
	if (length < 0)
	{
			printf("add fields header data failed, return length(%d) error.", length);
			return WEBCLIENT_NOK;
	}
	va_end(args);
	session->header->length += length;
	if (session->header->length >= session->header->size)
	{
			printf("not enough header buffer size(%d)!", session->header->size);
			return WEBCLIENT_NOK;
	}

	return WEBCLIENT_OK;
}



//解析响应数据的单一消息报头
const char* webclient_header_fields_get(webclient_session* session, const char* fields)
{
	char* resp_buf = NULL;
	size_t resp_buf_len = 0;
	char* dataPtr;
	char* mime_ptr = NULL;

	resp_buf = session->header->buffer;

	dataPtr = strstr(resp_buf,fields);
	if(dataPtr != NULL)
	{
		mime_ptr = strstr(dataPtr,":");
		if(mime_ptr != NULL)
		{
				mime_ptr += 1;
				while (*mime_ptr && (*mime_ptr == ' ' || *mime_ptr == '\t'))
					mime_ptr++;
				return mime_ptr;
		}
	}
	
	return NULL;
}

//获取请求头的长度
unsigned int webclient_header_length_response(webclient_session* session)
{
	return (strlen(session->header->buffer) - session->content_length - 4);
}

//获取服务器响应的状态码
unsigned char webclient_handle_response(webclient_session* session)
{
	int rc = 0;
	char* mime_buffer = NULL;
	char* mime_ptr = NULL;
	const char* transfer_encoding;
	int i;

	if(webclient_header_fields_get(session, "Content-Length") != NULL)
	{
		session->content_length = atoi(webclient_header_fields_get(session, "Content-Length"));
	}
	
	session->header->length = webclient_header_length_response(session);

	/* get HTTP status code */
	mime_ptr = web_strdup(session->header->buffer);
	if (strstr(mime_ptr, "HTTP/1."))
	{
		char* ptr = mime_ptr;

		ptr += strlen("HTTP/1.x");

		printf("ptr: %s\r\n", ptr);

		while (*ptr && (*ptr == ' ' || *ptr == '\t'))
				ptr++;

		/* Terminate string after status code */
		for (i = 0; ((ptr[i] != ' ') && (ptr[i] != '\t')); i++);
		ptr[i] = '\0';

		session->resp_status = (int)strtol(ptr, NULL, 10);

	}
	if (mime_ptr)
	{
			free(mime_ptr);
	}
	
	return session->resp_status;
}

//获取服务器返回的数据包
uint8_t* webclient_data_analysis(webclient_session* session)
{
	char* dataptr;
	char* mime_ptr = session->header->buffer;
	
	//printf("session->header->buffer:%s\r\n",session->header->buffer);
	
	dataptr = strstr(mime_ptr,"\r\n\r\n");
	if(dataptr != NULL)
	{
		dataptr += 4;
		return (uint8_t*)dataptr;
	}
	
	return NULL;
}



//客户端GET请求方法
void webclient_get_method(void)
{
	webclient_session* session;
	uint8_t uwRet = WEBCLIENT_NOK;
	uint8_t *dataPtr;
	
	session = webclient_session_create(RX_BUF_MAX_LEN);
	if(session == NULL)
	{
		printf("创建客户端失败\r\n");
		goto __exit;
	}
	
//	webclient_header_fields_add(session,"GET http://%s:%s/getBinFile?IMEI=868626044941824 HTTP/1.1\r\n",netDeviceInfo.staIPAddress,netDeviceInfo.staPort);
//	webclient_header_fields_add(session,"\r\n");
//	GET https://api.seniverse.com/v3/weather/now.json?key=smtq3n0ixdggurox&location=nanning&language=zh-Hans&unit=c HTTP/1.1\r\n	

	webclient_header_fields_add(session,"GET https://api.seniverse.com/v3/weather/now.json?key=smtq3n0ixdggurox&location=nanning&language=en&unit=c HTTP/1.1\r\n");
	webclient_header_fields_add(session,"Host:www.baidu.com\r\n");
	webclient_header_fields_add(session,"\r\n");
	
	if(ESP8266_DisconnectServer(0) != ESP8266_OK)	//断开服务器连接,
		goto __exit;
	
	if(ESP8266_Link_Server(enumTCP,"api.seniverse.com","80",Single_ID_0) == ESP8266_OK)	//连接服务器
	{
	
		uwRet = ESP8266_SendData(DISABLE,(uint8_t*)session->header->buffer,session->header->length,Single_ID_0);	//发送数据
		
		if(uwRet == WEBCLIENT_OK)	//发送成功
		{
			dataPtr = ESP8266_GetIPD(DISABLE,2000);	//解析服务器返回的数据
			if(dataPtr != NULL)
			{

				memset(session->header->buffer,0,session->header->size);
				session->header->length = 0;
				
				memcpy(session->header->buffer,dataPtr,session->header->size);
				
				if(webclient_handle_response(session) == 200)	//解析服务器返回的状态码
				{
				
					printf("strlen(session->header->buffer):%d\r\n",strlen(session->header->buffer));
					printf("session->header->length:%d\r\n",session->header->length);

					dataPtr = webclient_data_analysis(session);		//获取服务器返回的数据
					if(dataPtr != NULL)
					{
						if(strstr((char*)dataPtr,"+IPD,"))		//查找是否有IPD头
						{
							dataPtr = Filter_string((char*)dataPtr,(char*)"+IPD,",(char*)":");	//过滤IPD头
							if(dataPtr!=NULL)
							{
								printf("dataPtr:%s\r\n",dataPtr);
								//printf("session->content_length:%d\r\n",session->content_length);
							}
						}
						else
						{
								printf("dataPtr:%s\r\n",dataPtr);
						}
					}
					
				}
			}
		}
	}

__exit:
	if(session->header->buffer != NULL)
	{
		free(session->header->buffer);
		session->header->buffer=NULL;
	}
	if(session != NULL)
	{
		free(session);
		session = NULL;
	}
}

//客户端POST请求方法
void webclient_post_method(void)
{
	webclient_session* session;
	uint8_t uwRet = WEBCLIENT_NOK;
	uint8_t *dataPtr;
	
	session = webclient_session_create(RX_BUF_MAX_LEN);
	if(session == NULL)
	{
		printf("创建客户端失败\r\n");
		goto __exit;
	}
	
//	webclient_header_fields_add(session,"GET http://%s:%s/getBinFile?IMEI=868626044941824 HTTP/1.1\r\n",netDeviceInfo.staIPAddress,netDeviceInfo.staPort);
//	webclient_header_fields_add(session,"\r\n");
//	GET https://api.seniverse.com/v3/weather/now.json?key=smtq3n0ixdggurox&location=nanning&language=zh-Hans&unit=c HTTP/1.1\r\n	

	webclient_header_fields_add(session,"POST /devices/583402349/datapoints HTTP/1.1\r\n");
	webclient_header_fields_add(session,"api-key:rBIh6FFxeyW=kVJyybB2FzD5QAQ=\r\n");
	webclient_header_fields_add(session,"Host: api.heclouds.com\r\n");
	webclient_header_fields_add(session,"Content-Length:66\r\n");
	webclient_header_fields_add(session,"\r\n");
	webclient_header_fields_add(session,"{\"datastreams\":[{\"id\":\"test_stream\",\"datapoints\":[{\"value\":30}]}]}");
	
	if(ESP8266_DisconnectServer(0) != ESP8266_OK)	//断开服务器连接
		goto __exit;
	
	if(ESP8266_Link_Server(enumTCP,"api.heclouds.com","80",Single_ID_0) == ESP8266_OK)	//连接服务器
	{
	
		uwRet = ESP8266_SendData(DISABLE,(uint8_t*)session->header->buffer,session->header->length,Single_ID_0);	//发送数据
		
		if(uwRet == WEBCLIENT_OK)	//发送成功
		{
			dataPtr = ESP8266_GetIPD(DISABLE,2000);	//解析服务器返回的数据
			if(dataPtr != NULL)
			{

				memset(session->header->buffer,0,session->header->size);
				session->header->length = 0;
				
				memcpy(session->header->buffer,dataPtr,session->header->size);
				
				if(webclient_handle_response(session) == 200)	//解析服务器返回的状态码
				{
				
					printf("strlen(session->header->buffer):%d\r\n",strlen(session->header->buffer));
					printf("session->header->length:%d\r\n",session->header->length);

					dataPtr = webclient_data_analysis(session);		//获取服务器返回的数据
					if(dataPtr != NULL)
					{
						if(strstr((char*)dataPtr,"+IPD,"))		//查找是否有IPD头
						{
							dataPtr = Filter_string((char*)dataPtr,(char*)"+IPD,",(char*)":");	//过滤IPD头
							if(dataPtr!=NULL)
							{
								printf("dataPtr:%s\r\n",dataPtr);
								//printf("session->content_length:%d\r\n",session->content_length);
							}
						}
						else
						{
								printf("dataPtr:%s\r\n",dataPtr);
						}
					}
					
				}
			}
		}
	}

__exit:
	if(session->header->buffer != NULL)
	{
		free(session->header->buffer);
		session->header->buffer=NULL;
	}
	if(session != NULL)
	{
		free(session);
		session = NULL;
	}
}

在StringUtil.h中编写以下代码

#ifndef __STRING_UTIL_h
#define __STRING_UTIL_h
#include "string.h"
#include <ctype.h>
#include <stdlib.h>
#include "usart.h"

int find_end(char * usart_buffer, int number);
int Find_string(char *pcBuf,char *left,char *right, char *pcRes);
void smart_array(unsigned char* addr,unsigned char *ip);
void Hex2Str(char *pbDest, char *pbSrc, int nLen);
unsigned char* Filter_string(char* pcBuf, char* left, char* right);
#endif

在StringUtil.c中编写以下代码

#include "StringUtil.h"


/**
*@brief	 	ip网络地址转换
*@param		adr:地址 ip:ip
*@return	无
*/
void smart_array(unsigned char* addr,unsigned char *ip)
{
    int i;
    char taddr[30];
    char * nexttok;
    char num;
    strcpy(taddr,(char *)addr);
    nexttok = taddr;
    for(i = 0; i < 4 ; i++)
    {
        nexttok = strtok(nexttok,".");
//		if(nexttok[0] == '0' && nexttok[1] == 'x') num = atoi16(nexttok+2,0x10);
//		else num = atoi16(nexttok,10);
        ip[i] = num;
        nexttok = NULL;
    }
}
/***********************************************************
  函数名称:Find_string(char *pcBuf,char*left,char*right, char *pcRes)
  函数功能:寻找特定字符串
  入口参数:
           char *pcBuf 为传入的字符串
           char*left   为搜索字符的左边标识符  例如:"["
           char*right  为搜索字符的右边标识符  例如:"]"
		   char *pcRes 为输出转存的字符串数组
  返回值:用来校验是否成功,无所谓的。
  备注: left字符需要唯一,right字符从left后面开始唯一即可
 服务器下发命令举例:+MQTTPUBLISH: 0,0,0,0,/device/NB/zx99999999999999_back,6,[reastrobot]
 此函数会操作内存空间  强烈建议 提前清空buf   memset(Find_token,0x00,sizeof(Find_token));
***********************************************************/
int Find_string(char *pcBuf,char *left,char *right, char *pcRes)
{
    char *pcBegin = NULL;
    char *pcEnd = NULL;
    pcBegin = strstr(pcBuf, left);               //找到第一次出现的位置
    pcEnd = strstr(pcBegin+strlen(left), right); //找到右边标识第一次出现位置
    if(pcBegin == NULL || pcEnd == NULL || pcBegin > pcEnd)
    {
        printf("string name not found!\n");
        return 0;
    }
    else
    {
        pcBegin += strlen(left);
        memcpy(pcRes, pcBegin, pcEnd-pcBegin);
        return 1;
    }
}

//+IPD, 268:hello world\r\n
//过滤left和right之间的字符串,返回过滤之后的字符串
unsigned char* Filter_string(char* pcBuf, char* left, char* right)
{
    char* ptrIPD;

    ptrIPD = strstr((char*)pcBuf, left);				//搜索“left”头
    if (ptrIPD == NULL)										
    {
        //						UsartPrintf(USART_DEBUG, "\"left\" not found\r\n");
    }
    else
    {
        ptrIPD = strstr(ptrIPD, right);							//找到'right'
        if (ptrIPD != NULL)
        {
            ptrIPD+=strlen(right);
            return (unsigned char*)(ptrIPD);
        }
        else
            return NULL;
    }
}


//int Smart_array(char *pcBuf,char *fu)
//{
//memcpy(&citc_server_ip[0],back_ip,strstr(back_ip,".")-back_ip);
//  char *pcBegin = NULL;
//	int8_t len =0;
//	pcBegin = strstr(pcBuf, fu);//找到第一次出现的位置
//	memcpy(&pcRes[i], pcBuf,pcBegin-pcBuf);
//	}
//	 len= strlen(pcBuf);
//	 pcBegin = strstr(pcBuf, fu);//找到第一次出现的位置
//	 memcpy(&pcRes[0], pcBuf,pcBegin-pcBuf);
//}

//寻找字符后面最近的结束符
//int find_end(char * usart_buffer, int number) {
//  int i;
//  for (i = 0; i < 100; i++) {
//    if ((usart_buffer[number + i] == '/') && (usart_buffer[number + i + 1] == '>')) {
//      return number + i+2 ;   //如果有换行符  需要加4
//    }
//  }
//}

//智能查找和匹配字符串
int8_t Find_AttributeStringAll(char *pcBuf, char *pcRest,uint16_t row,uint8_t col, char *left, char *right,uint8_t *Num)
{
    char pcFind[20] = {0};
    char *pcBegin = NULL;
    char *pcEnd = NULL;

    pcEnd  = pcBuf;
    while(1)
    {
        memset(pcFind,0,20);
        pcBegin = strstr(pcEnd+1, left);
        if((pcBegin == NULL) || (strcmp(pcBegin,"}") == 0))
        {
            printf("找到指定字符 !\n");
            return 1;
        }
        else
        {
            pcEnd = strstr(pcBegin+strlen(left), right);
            if ((pcEnd == NULL) || (pcBegin > pcEnd))
            {
                printf("Mail name not found!\n");
                return -1;
            }
            else
            {
                if(*Num>row)
                {
                    return 1;
                }
                else
                {
                    pcBegin += strlen(left);
                    memcpy(pcFind, pcBegin, pcEnd - pcBegin);
                    memset(pcRest+*Num*col,0,col);
                    memcpy(pcRest+*Num*col,pcFind,sizeof(pcFind));
                    (*Num) ++;
                }
            }
        }
    }
}

void Hex2Str(char *pbDest, char *pbSrc, int nLen)
{
    char    ddl,ddh;
    int i;

    for (i=0; i<nLen; i++)
    {
        ddh = 48 + pbSrc[i] / 16;
        ddl = 48 + pbSrc[i] % 16;
        if (ddh > 57) ddh = ddh + 7;
        if (ddl > 57) ddl = ddl + 7;
        pbDest[i*2] = ddh;
        pbDest[i*2+1] = ddl;
    }

    pbDest[nLen*2] = '\0';
}

void Str2Hex(char* str, char* hex)
{

    const char* cHex = "0123456789ABCDEF";
    int i=0;
    for(int j =0; j < strlen(str); j++)
    {
        unsigned int a =  (unsigned int) str[j];
        hex[i++] = cHex[(a & 0xf0) >> 4];
        hex[i++] = cHex[(a & 0x0f)];
    }
    hex[i] = '\0';
}

在main.c中编写以下代码

/* USER CODE BEGIN 0 */

#define REQUEST_METHOD 	0	//0:GET请求,1:POST请求
/* USER CODE END 0 */

int main(void)
{
  /* USER CODE BEGIN 1 */
	unsigned char* dataPtr = NULL;
	uint32_t request_time = 0;
	uint32_t netErr_time = 0;
	ESP8266_RETTYPE uwRet = ESP8266_NOK;
	uint32_t total_len=0;

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_LPUART1_UART_Init();
  MX_USART1_UART_Init();
  MX_TIM2_Init();
  /* USER CODE BEGIN 2 */
	
	TIM_Interupt_Enable(); //使能串口中断
	
	USART_Interupt_Enable(); //使能定时器中断

	
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
		
		if(!netDeviceInfo.netWork)	//如果网络未连接
		{
			if(NET_DEVICE_Init() == ESP8266_OK)	
			{
				printf("初始化成功\r\n");
			}
		}
		
		if(time2Count - request_time >= 10000)		//(1ms * 2000)相当于延时2秒钟
		{
			if(netDeviceInfo.netWork)//如果网络连接成功
			{
#if REQUEST_METHOD
					webclient_get_method();	
#else
					webclient_post_method();
#endif
		
			}
		}
	
  }
  /* USER CODE END 3 */
}


4、实验现象

实现的功能
1、上电自动连接WIFI
2、如果是POST请求,则请求POST接口(我这里用的是ONENET的POST接口)
3、如果是GET请求,则请求GET接口(我这里用的是心知天气的GET接口)

POST请求(Onenet物联网平台)
在这里插入图片描述
GET请求(心知天气)
在这里插入图片描述

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