├── README.md
└── mqtt_tcp_pub_sub.c


/README.md:
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1 | # MQTT-ESP-IDF
2 | 
3 | ESP IDF MQTT Publish and Subscribe via Mosquitto broker for esp32
4 | 


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/mqtt_tcp_pub_sub.c:
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  1 | #include <stdio.h>
  2 | #include <stdint.h>
  3 | #include <stddef.h>
  4 | #include <string.h>
  5 | #include "esp_wifi.h"
  6 | #include "esp_system.h"
  7 | #include "nvs_flash.h"
  8 | #include "esp_event.h"
  9 | #include "esp_netif.h"
 10 | #include "my_data.h"
 11 | 
 12 | #include "freertos/FreeRTOS.h"
 13 | #include "freertos/task.h"
 14 | #include "freertos/semphr.h"
 15 | #include "freertos/queue.h"
 16 | 
 17 | #include "lwip/sockets.h"
 18 | #include "lwip/dns.h"
 19 | #include "lwip/netdb.h"
 20 | 
 21 | #include "esp_log.h"
 22 | #include "mqtt_client.h"
 23 | 
 24 | static const char *TAG = "MQTT_TCP";
 25 | 
 26 | static void wifi_event_handler(void *event_handler_arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 27 | {
 28 |     switch (event_id)
 29 |     {
 30 |     case WIFI_EVENT_STA_START:
 31 |         printf("WiFi connecting ... \n");
 32 |         break;
 33 |     case WIFI_EVENT_STA_CONNECTED:
 34 |         printf("WiFi connected ... \n");
 35 |         break;
 36 |     case WIFI_EVENT_STA_DISCONNECTED:
 37 |         printf("WiFi lost connection ... \n");
 38 |         break;
 39 |     case IP_EVENT_STA_GOT_IP:
 40 |         printf("WiFi got IP ... \n\n");
 41 |         break;
 42 |     default:
 43 |         break;
 44 |     }
 45 | }
 46 | 
 47 | void wifi_connection()
 48 | {
 49 |     // 1 - Wi-Fi/LwIP Init Phase
 50 |     esp_netif_init();                    // TCP/IP initiation 					s1.1
 51 |     esp_event_loop_create_default();     // event loop 			                s1.2
 52 |     esp_netif_create_default_wifi_sta(); // WiFi station 	                    s1.3
 53 |     wifi_init_config_t wifi_initiation = WIFI_INIT_CONFIG_DEFAULT();
 54 |     esp_wifi_init(&wifi_initiation); // 					                    s1.4
 55 |     // 2 - Wi-Fi Configuration Phase
 56 |     esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, wifi_event_handler, NULL);
 57 |     esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, wifi_event_handler, NULL);
 58 |     wifi_config_t wifi_configuration = {
 59 |         .sta = {
 60 |             .ssid = SSID,
 61 |             .password = PASS}};
 62 |     esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_configuration);
 63 |     // 3 - Wi-Fi Start Phase
 64 |     esp_wifi_start();
 65 |     // 4- Wi-Fi Connect Phase
 66 |     esp_wifi_connect();
 67 | }
 68 | 
 69 | static esp_err_t mqtt_event_handler_cb(esp_mqtt_event_handle_t event)
 70 | {
 71 |     esp_mqtt_client_handle_t client = event->client;
 72 |     switch (event->event_id)
 73 |     {
 74 |     case MQTT_EVENT_CONNECTED:
 75 |         ESP_LOGI(TAG, "MQTT_EVENT_CONNECTED");
 76 |         esp_mqtt_client_subscribe(client, "my_topic", 0);
 77 |         esp_mqtt_client_publish(client, "my_topic", "Hi to all from ESP32 .........", 0, 1, 0);
 78 |         break;
 79 |     case MQTT_EVENT_DISCONNECTED:
 80 |         ESP_LOGI(TAG, "MQTT_EVENT_DISCONNECTED");
 81 |         break;
 82 |     case MQTT_EVENT_SUBSCRIBED:
 83 |         ESP_LOGI(TAG, "MQTT_EVENT_SUBSCRIBED, msg_id=%d", event->msg_id);
 84 |         break;
 85 |     case MQTT_EVENT_UNSUBSCRIBED:
 86 |         ESP_LOGI(TAG, "MQTT_EVENT_UNSUBSCRIBED, msg_id=%d", event->msg_id);
 87 |         break;
 88 |     case MQTT_EVENT_PUBLISHED:
 89 |         ESP_LOGI(TAG, "MQTT_EVENT_PUBLISHED, msg_id=%d", event->msg_id);
 90 |         break;
 91 |     case MQTT_EVENT_DATA:
 92 |         ESP_LOGI(TAG, "MQTT_EVENT_DATA");
 93 |         printf("\nTOPIC=%.*s\r\n", event->topic_len, event->topic);
 94 |         printf("DATA=%.*s\r\n", event->data_len, event->data);
 95 |         break;
 96 |     case MQTT_EVENT_ERROR:
 97 |         ESP_LOGI(TAG, "MQTT_EVENT_ERROR");
 98 |         break;
 99 |     default:
100 |         ESP_LOGI(TAG, "Other event id:%d", event->event_id);
101 |         break;
102 |     }
103 |     return ESP_OK;
104 | }
105 | 
106 | static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data)
107 | {
108 |     ESP_LOGD(TAG, "Event dispatched from event loop base=%s, event_id=%d", base, event_id);
109 |     mqtt_event_handler_cb(event_data);
110 | }
111 | 
112 | static void mqtt_app_start(void)
113 | {
114 |     esp_mqtt_client_config_t mqtt_cfg = {
115 |         .uri = "mqtt://mqtt.eclipseprojects.io",
116 |     };
117 |     esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
118 |     esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, client);
119 |     esp_mqtt_client_start(client);
120 | }
121 | 
122 | void app_main(void)
123 | {
124 |     nvs_flash_init();
125 |     wifi_connection();
126 | 
127 |     vTaskDelay(2000 / portTICK_PERIOD_MS);
128 |     printf("WIFI was initiated ...........\n");
129 | 
130 |     mqtt_app_start();
131 | }


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