JSON ESP8266 NONOS SDK TUTORIAL - HƯỚNG DẪN SỬ DỤNG JSON TRÊN ESP8266 NONOS SDK

Hello everyone!
Today, I will show you how to use JSON API on ESP8266 NONOS SDK.

Firstly, we need to have some things:
- ESP8266 NONOS SDK Version 3.0 (https://www.espressif.com/en/products/hardware/esp8266ex/resources).
- Compiler (I'm using SlickEdit 16.0, you can use sublime text or others ...).
- ESP8266 Lubuntu.
- Serial monitor tool.

Now, get started!

Step 1: Copy 02 files ESP8266_NONOS_SDK-3.0\examples\IoT_Demo\user\user_json.c and ESP8266_NONOS_SDK-3.0\examples\IoT_Demo\include\user_json.h to your project folder as the image below:

Step 2: go to user_main.c in user folder and edit them:
- Create JSON Objects and function to call back.

LOCAL int ICACHE_FLASH_ATTR
json_get(struct jsontree_context *js_ctx)
{
    os_printf("\njson get\n");
    const char *path = jsontree_path_name(js_ctx, js_ctx->depth - 1);

    if (os_strncmp(path, "switch", 6) == 0) {
        os_printf("\r\n write the switch \r\n");
        jsontree_write_string(js_ctx, "off");
    }

    else if (os_strncmp(path, "thecat", 6) == 0) {
        os_printf("\r\n write to thecat \r\n");
        jsontree_write_string(js_ctx, "male");
    }

    else if (os_strncmp(path, "thedog", 6) == 0) {
        os_printf("\r\n write to thedog \r\n");
        jsontree_write_string(js_ctx, "black");
    }
    return 0;
}

LOCAL int ICACHE_FLASH_ATTR
json_set(struct jsontree_context *js_ctx, struct jsonparse_state *parser)
{
    os_printf("\n==================>json set state: %d\n", js_ctx->callback_state);

    int type;
    while ((type = jsonparse_next(parser)) != 0) {

        if (type == JSON_TYPE_PAIR_NAME) {
            char buffer[10];
            os_bzero(buffer, 10);

            os_printf("JSON_TYPE_PAIR\n");

            jsonparse_next(parser);
            jsonparse_next(parser);

            uint32_t jslen = jsonparse_get_len(parser);

            char buff[jslen];

            jsonparse_copy_value(parser, buff, jslen + 1);

            int i = 0;
            for (i = 0; i < jslen + 1; i++) {
                os_printf("%c", buff[i]);
            }
            os_printf("\r\n");


            #if 0
            if (jsonparse_strcmp_value(parser, "name") == 0) {
                os_printf("\n---name---\n");

              jsonparse_next(parser);
              jsonparse_next(parser);


              jsonparse_copy_value(parser, buffer, sizeof(buffer));

              int i = 0;
              for (i = 0; i < 10; i++) {
                  os_printf("%c", buffer[i]);
              }
              os_printf("\n");

              if (!strcoll(buffer, "John")) {
                  os_printf("=====John==========\n");
                  uint32_t jslen = jsonparse_get_len(parser);

                  os_printf("=>>>>>>%d>>>\r\n", jslen);
              }
            }

            if (jsonparse_strcmp_value(parser, "age") == 0) {

                os_printf("\n===age\n");
                uint32_t jslen = jsonparse_get_len(parser);

                os_printf("=>>>>>>%d>>>\r\n", jslen);

                jsonparse_next(parser);
                jsonparse_next(parser);

                jsonparse_copy_value(parser, buffer, sizeof(buffer));

                if (!strcoll(buffer, "31")) {
                  os_printf("=====31==========\n");
                }

            }

            if (jsonparse_strcmp_value(parser, "city") == 0) {

                jsonparse_next(parser);
                jsonparse_next(parser);

                os_printf("=>>>>>>city>>>\r\n");

                uint32_t jslen = jsonparse_get_len(parser);

                os_printf("=>>>>>>%d>>>\r\n", jslen);

                char buff[jslen];

                jsonparse_copy_value(parser, buff, jslen + 1);

                int i = 0;
                for (i = 0; i < jslen; i++) {
                    os_printf("%c", buff[i]);
                }

            }
            #endif
         
        }
    }
    return 0;
}

LOCAL struct jsontree_callback switch_callback =
    JSONTREE_CALLBACK(json_get, json_set);

// 01 objecs
// JSONTREE_OBJECT(switch_tree,
//                JSONTREE_PAIR("switch", &switch_callback)
//                );

// multy objects
JSONTREE_OBJECT(switch_tree,
                JSONTREE_PAIR("thecat", &switch_callback),
                JSONTREE_PAIR("switch", &switch_callback),
                JSONTREE_PAIR("thedog", &switch_callback)

                );

• json_get function: generater String as JSON format.
• switch_callback: call back function when set or get json format string.
• switch_tree: name of json object.
  

Generate a JSON Format:

LOCAL void ICACHE_FLASH_ATTR
JSON_TEST_FUNC(void){
    int i = 0;

    #if 1
        // test write json test
        char *json_buf = NULL;
        json_buf = (char *)os_zalloc(jsonSize);

        os_printf("\r\n sizeof before: %d \r\n", os_strlen(json_buf));

        //json_ws_send((struct jsontree_value *)&switch_tree, "devices", json_buf); // 1 object
        json_ws_send((struct jsontree_value *)&switch_tree, "thecat, switch, thedog", json_buf); // multy objects

        os_printf("\r\n sizeof after: %d \r\n", os_strlen(json_buf));

        
        for (i = 0; i < os_strlen(json_buf); i++) {
            os_printf("%c", json_buf[i]);
        }
        os_printf("\r\n");
    #endif

    #if 0
        // read json - OK
        char *data_buf = "{\"name\": \"John\", \"age\": \"31\", \"city\" : \"New York\"}";
        struct jsontree_context js;
        jsontree_setup(&js, (struct jsontree_value *)&switch_tree, json_putchar);

        json_parse(&js, data_buf);
    #endif

}

FULL CODE:

/*
 * ESPRESSIF MIT License
 *
 * Copyright (c) 2016 <ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD>
 *
 * Permission is hereby granted for use on ESPRESSIF SYSTEMS ESP8266 only, in which case,
 * it is free of charge, to any person obtaining a copy of this software and associated
 * documentation files (the "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished
 * to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#include "ets_sys.h"
#include "osapi.h"

#include "user_interface.h"

#include "user_json.h"
#include "mem.h"

#if ((SPI_FLASH_SIZE_MAP == 0) || (SPI_FLASH_SIZE_MAP == 1))
#error "The flash map is not supported"
#elif (SPI_FLASH_SIZE_MAP == 2)
#define SYSTEM_PARTITION_OTA_SIZE 0x6A000
#define SYSTEM_PARTITION_OTA_2_ADDR 0x81000
#define SYSTEM_PARTITION_RF_CAL_ADDR 0xfb000
#define SYSTEM_PARTITION_PHY_DATA_ADDR 0xfc000
#define SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR 0xfd000
#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR           0x7c000
#elif (SPI_FLASH_SIZE_MAP == 3)
#define SYSTEM_PARTITION_OTA_SIZE 0x6A000
#define SYSTEM_PARTITION_OTA_2_ADDR 0x81000
#define SYSTEM_PARTITION_RF_CAL_ADDR 0x1fb000
#define SYSTEM_PARTITION_PHY_DATA_ADDR 0x1fc000
#define SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR 0x1fd000
#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR           0x7c000
#elif (SPI_FLASH_SIZE_MAP == 4)
#define SYSTEM_PARTITION_OTA_SIZE 0x6A000
#define SYSTEM_PARTITION_OTA_2_ADDR 0x81000
#define SYSTEM_PARTITION_RF_CAL_ADDR 0x3fb000
#define SYSTEM_PARTITION_PHY_DATA_ADDR 0x3fc000
#define SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR 0x3fd000
#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR           0x7c000
#elif (SPI_FLASH_SIZE_MAP == 5)
#define SYSTEM_PARTITION_OTA_SIZE 0x6A000
#define SYSTEM_PARTITION_OTA_2_ADDR 0x101000
#define SYSTEM_PARTITION_RF_CAL_ADDR 0x1fb000
#define SYSTEM_PARTITION_PHY_DATA_ADDR 0x1fc000
#define SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR 0x1fd000
#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR           0xfc000
#elif (SPI_FLASH_SIZE_MAP == 6)
#define SYSTEM_PARTITION_OTA_SIZE 0x6A000
#define SYSTEM_PARTITION_OTA_2_ADDR 0x101000
#define SYSTEM_PARTITION_RF_CAL_ADDR 0x3fb000
#define SYSTEM_PARTITION_PHY_DATA_ADDR 0x3fc000
#define SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR 0x3fd000
#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR           0xfc000
#else
#error "The flash map is not supported"
#endif

#define SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM                SYSTEM_PARTITION_CUSTOMER_BEGIN

uint32 priv_param_start_sec;

static const partition_item_t at_partition_table[] = {
    { SYSTEM_PARTITION_BOOTLOADER, 0x0, 0x1000},
    { SYSTEM_PARTITION_OTA_1,    0x1000, SYSTEM_PARTITION_OTA_SIZE},
    { SYSTEM_PARTITION_OTA_2,    SYSTEM_PARTITION_OTA_2_ADDR, SYSTEM_PARTITION_OTA_SIZE},
    { SYSTEM_PARTITION_RF_CAL,  SYSTEM_PARTITION_RF_CAL_ADDR, 0x1000},
    { SYSTEM_PARTITION_PHY_DATA, SYSTEM_PARTITION_PHY_DATA_ADDR, 0x1000},
    { SYSTEM_PARTITION_SYSTEM_PARAMETER, SYSTEM_PARTITION_SYSTEM_PARAMETER_ADDR, 0x3000},
    { SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM,             SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM_ADDR,          0x1000},
};

void ICACHE_FLASH_ATTR user_pre_init(void)
{
    if(!system_partition_table_regist(at_partition_table, sizeof(at_partition_table)/sizeof(at_partition_table[0]),SPI_FLASH_SIZE_MAP)) {
os_printf("system_partition_table_regist fail\r\n");
while(1);
}
}


LOCAL int ICACHE_FLASH_ATTR
json_get(struct jsontree_context *js_ctx)
{
    os_printf("\njson get\n");
    const char *path = jsontree_path_name(js_ctx, js_ctx->depth - 1);

    if (os_strncmp(path, "switch", 6) == 0) {
        os_printf("\r\n write the switch \r\n");
        jsontree_write_string(js_ctx, "off");
    }

    else if (os_strncmp(path, "thecat", 6) == 0) {
        os_printf("\r\n write to thecat \r\n");
        jsontree_write_string(js_ctx, "male");
    }

    else if (os_strncmp(path, "thedog", 6) == 0) {
        os_printf("\r\n write to thedog \r\n");
        jsontree_write_string(js_ctx, "black");
    }
    return 0;
}

LOCAL int ICACHE_FLASH_ATTR
json_set(struct jsontree_context *js_ctx, struct jsonparse_state *parser)
{
    os_printf("\n==================>json set state: %d\n", js_ctx->callback_state);

    int type;
    while ((type = jsonparse_next(parser)) != 0) {

        if (type == JSON_TYPE_PAIR_NAME) {
            char buffer[10];
            os_bzero(buffer, 10);

            os_printf("JSON_TYPE_PAIR\n");

            jsonparse_next(parser);
            jsonparse_next(parser);

            uint32_t jslen = jsonparse_get_len(parser);

            char buff[jslen];

            jsonparse_copy_value(parser, buff, jslen + 1);

            int i = 0;
            for (i = 0; i < jslen + 1; i++) {
                os_printf("%c", buff[i]);
            }
            os_printf("\r\n");


            #if 0
            if (jsonparse_strcmp_value(parser, "name") == 0) {
                os_printf("\n---name---\n");

              jsonparse_next(parser);
              jsonparse_next(parser);


              jsonparse_copy_value(parser, buffer, sizeof(buffer));

              int i = 0;
              for (i = 0; i < 10; i++) {
                  os_printf("%c", buffer[i]);
              }
              os_printf("\n");

              if (!strcoll(buffer, "John")) {
                  os_printf("=====John==========\n");
                  uint32_t jslen = jsonparse_get_len(parser);

                  os_printf("=>>>>>>%d>>>\r\n", jslen);
              }
            }

            if (jsonparse_strcmp_value(parser, "age") == 0) {

                os_printf("\n===age\n");
                uint32_t jslen = jsonparse_get_len(parser);

                os_printf("=>>>>>>%d>>>\r\n", jslen);

                jsonparse_next(parser);
                jsonparse_next(parser);

                jsonparse_copy_value(parser, buffer, sizeof(buffer));

                if (!strcoll(buffer, "31")) {
                  os_printf("=====31==========\n");
                }

            }

            if (jsonparse_strcmp_value(parser, "city") == 0) {

                jsonparse_next(parser);
                jsonparse_next(parser);

                os_printf("=>>>>>>city>>>\r\n");

                uint32_t jslen = jsonparse_get_len(parser);

                os_printf("=>>>>>>%d>>>\r\n", jslen);

                char buff[jslen];

                jsonparse_copy_value(parser, buff, jslen + 1);

                int i = 0;
                for (i = 0; i < jslen; i++) {
                    os_printf("%c", buff[i]);
                }

            }
            #endif
           
        }
    }
    return 0;
}

LOCAL struct jsontree_callback switch_callback =
    JSONTREE_CALLBACK(json_get, json_set);

// 01 objecs
// JSONTREE_OBJECT(switch_tree,
//                JSONTREE_PAIR("switch", &switch_callback)
//                );

// multy objects
JSONTREE_OBJECT(switch_tree,
                JSONTREE_PAIR("thecat", &switch_callback),
                JSONTREE_PAIR("switch", &switch_callback),
                JSONTREE_PAIR("thedog", &switch_callback)
                );


LOCAL void ICACHE_FLASH_ATTR
JSON_TEST_FUNC(void){
    int i = 0;

    #if 1
        // test write json test
        char *json_buf = NULL;
        json_buf = (char *)os_zalloc(jsonSize);

        os_printf("\r\n sizeof before: %d \r\n", os_strlen(json_buf));

        //json_ws_send((struct jsontree_value *)&switch_tree, "devices", json_buf); // 1 object
        json_ws_send((struct jsontree_value *)&switch_tree, "thecat, switch, thedog", json_buf); // multy objects

        os_printf("\r\n sizeof after: %d \r\n", os_strlen(json_buf));

       
        for (i = 0; i < os_strlen(json_buf); i++) {
            os_printf("%c", json_buf[i]);
        }
        os_printf("\r\n");
    #endif

    #if 0
        // read json - OK
        char *data_buf = "{\"name\": \"John\", \"age\": \"31\", \"city\" : \"New York\"}";
        struct jsontree_context js;
        jsontree_setup(&js, (struct jsontree_value *)&switch_tree, json_putchar);

        json_parse(&js, data_buf);
    #endif
}
/******************************************************************************
 * FunctionName : user_init
 * Description  : entry of user application, init user function here
 * Parameters   : none
 * Returns      : none
*******************************************************************************/
void ICACHE_FLASH_ATTR
user_init(void)
{
    partition_item_t partition_item;
    os_printf("SDK version:%s\n", system_get_sdk_version());

    if (!system_partition_get_item(SYSTEM_PARTITION_CUSTOMER_PRIV_PARAM, &partition_item)) {
        os_printf("Get partition information fail\n");
    }
    priv_param_start_sec = partition_item.addr/SPI_FLASH_SEC_SIZE;

    JSON_TEST_FUNC();
}

Video tutorial: