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main/main.c

+/* HTTP GET Example using plain POSIX sockets
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+#include <string.h>
+#include <stdio.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/event_groups.h"
+#include "esp_system.h"
+#include "esp_wifi.h"
+#include "esp_event_loop.h"
+#include "esp_log.h"
+#include "nvs_flash.h"
+#include "esp_attr.h"
+#include "lwip/err.h"
+#include "lwip/sockets.h"
+#include "lwip/sys.h"
+#include "lwip/netdb.h"
+#include "lwip/dns.h"
+
+#include "esp_tls.h"
+
+#include "lwip/err.h"
+#include "apps/sntp/sntp.h"
+
+
+static void initialize_sntp(void);
+static void obtain_time(void);
+
+int average_temp = 23;
+
+uint8_t temprature_sens_read();
+
+/* The examples use simple WiFi configuration that you can set via
+   'make menuconfig'.
+   If you'd rather not, just change the below entries to strings with
+   the config you want - ie #define EXAMPLE_WIFI_SSID "mywifissid"
+*/
+#define EXAMPLE_WIFI_SSID "BV7000 Pro"
+#define EXAMPLE_WIFI_PASS "sia12345"
+
+/* FreeRTOS event group to signal when we are connected & ready to make a request */
+static EventGroupHandle_t wifi_event_group;
+
+/* The event group allows multiple bits for each event,
+   but we only care about one event - are we connected
+   to the AP with an IP? */
+const int CONNECTED_BIT = BIT0;
+
+/* Constants that aren't configurable in menuconfig */
+// #define WEB_SERVER "example.com"
+#define WEB_SERVER "c8y.ttu.ee"
+#define WEB_PORT 80
+#define WEB_URL "http://example.com/"
+
+static const char *TAG = "WIFI";
+
+
+
+static esp_err_t event_handler(void *ctx, system_event_t *event)
+{
+    switch(event->event_id) {
+    case SYSTEM_EVENT_STA_START:
+        esp_wifi_connect();
+        break;
+    case SYSTEM_EVENT_STA_GOT_IP:
+        xEventGroupSetBits(wifi_event_group, CONNECTED_BIT);
+        break;
+    case SYSTEM_EVENT_STA_DISCONNECTED:
+        /* This is a workaround as ESP32 WiFi libs don't currently
+           auto-reassociate. */
+        esp_wifi_connect();
+        xEventGroupClearBits(wifi_event_group, CONNECTED_BIT);
+        break;
+    default:
+        break;
+    }
+    return ESP_OK;
+}
+
+static void initialise_wifi(void)
+{
+    tcpip_adapter_init();
+    wifi_event_group = xEventGroupCreate();
+    ESP_ERROR_CHECK( esp_event_loop_init(event_handler, NULL) );
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK( esp_wifi_init(&cfg) );
+    ESP_ERROR_CHECK( esp_wifi_set_storage(WIFI_STORAGE_RAM) );
+    wifi_config_t wifi_config = {
+        .sta = {
+            .ssid = EXAMPLE_WIFI_SSID,
+            .password = EXAMPLE_WIFI_PASS,
+        },
+    };
+    ESP_LOGI(TAG, "Setting WiFi configuration SSID %s...", wifi_config.sta.ssid);
+    ESP_ERROR_CHECK( esp_wifi_set_mode(WIFI_MODE_STA) );
+    ESP_ERROR_CHECK( esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config) );
+    ESP_ERROR_CHECK( esp_wifi_start() );
+}
+
+static void http_get_task(void *pvParameters)
+{
+    const struct addrinfo hints = {
+        .ai_family = AF_INET,
+        .ai_socktype = SOCK_STREAM,
+    };
+
+    //-------------------------------------------------------------------------------------------
+    // setting up the system clock!
+    //-------------------------------------------------------------------------------------------
+    struct addrinfo *res;
+    struct in_addr *addr;
+    int s, r;
+    char recv_buf[128];
+
+
+    time_t now;
+    struct tm timeinfo;
+    time(&now);
+    localtime_r(&now, &timeinfo);
+        // Is time set? If not, tm_year will be (1970 - 1900).
+    ESP_LOGI(TAG, "year: %d", timeinfo.tm_year);
+    if (timeinfo.tm_year < (2019 - 1900)) {
+              ESP_LOGI(TAG, "Time is not set yet. Connecting to WiFi and getting time over NTP.");
+              obtain_time();
+              // update 'now' variable with current time
+              time(&now);
+        }
+    char strftime_buf[64];
+    setenv("TZ", "UTC", 1); // set time to UTC will fix it later with offset!
+    tzset();
+    localtime_r(&now, &timeinfo);
+    strftime(strftime_buf, sizeof(strftime_buf), "%c", &timeinfo);
+    ESP_LOGI(TAG, "The current date/time in UTC  is: %s", strftime_buf);
+
+    while(1) {
+        /* Wait for the callback to set the CONNECTED_BIT in the
+           event group.
+        */
+        xEventGroupWaitBits(wifi_event_group, CONNECTED_BIT,
+                            false, true, portMAX_DELAY);
+        ESP_LOGI(TAG, "Connected to AP");
+
+        int err = getaddrinfo(WEB_SERVER, "80", &hints, &res);
+
+        if(err != 0 || res == NULL) {
+            ESP_LOGE(TAG, "DNS lookup failed err=%d res=%p", err, res);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
+            continue;
+        }
+
+        /* Code to print the resolved IP.
+           Note: inet_ntoa is non-reentrant, look at ipaddr_ntoa_r for "real" code */
+        addr = &((struct sockaddr_in *)res->ai_addr)->sin_addr;
+        ESP_LOGI(TAG, "DNS lookup succeeded. IP=%s", inet_ntoa(*addr));
+
+        s = socket(res->ai_family, res->ai_socktype, 0);
+        if(s < 0) {
+            ESP_LOGE(TAG, "... Failed to allocate socket.");
+            freeaddrinfo(res);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
+            continue;
+        }
+        ESP_LOGI(TAG, "... allocated socket");
+
+        if(connect(s, res->ai_addr, res->ai_addrlen) != 0) {
+            ESP_LOGE(TAG, "... socket connect failed errno=%d", errno);
+            close(s);
+            freeaddrinfo(res);
+            vTaskDelay(4000 / portTICK_PERIOD_MS);
+            continue;
+        }
+
+        ESP_LOGI(TAG, "... connected");
+        freeaddrinfo(res);
+
+
+        time(&now);
+        localtime_r(&now, &timeinfo);
+        // time format: 2019-03-11T13:06:14.000+02:00
+        ESP_LOGI(TAG, "%d-%d-%dT%d:%d:%d.000+02:00", timeinfo.tm_year+1900, timeinfo.tm_mon+1, timeinfo.tm_mday, timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);
+
+        const char *initialString = "POST /measurement/measurements HTTP/1.1\nHost: c8y.ttu.ee\nContent-Length: 370\nAuthorization: Basic aW1sYWJzdHVkZW50QGdtYWlsLmNvbTpkYXNkOTEyOFNES0dzZGEhZDI=\nContent-Type: application/json\n\n{\n  \"classroom\": {\n      \"Temperature\": { \n          \"value\": ";
+        const char *middlestring =",\n            \"unit\": \"C\" }\n        ,\n       \"Humidity\": { \n          \"value\": 80,\n            \"unit\": \"%\" }\n        ,\n \t\"Speed\": { \n          \"value\": 10,\n            \"unit\": \"km/h\" }\n        },\n    \"time\":\"";
+        const char *finalString ="\", \n    \"source\": {\n      \"id\":\"480186\" }, \n    \"type\": \"classroom\"\n}\n";
+
+        char *REQUEST = malloc(strlen(initialString)+strlen(middlestring)+strlen(finalString)+31);
+
+        sprintf(REQUEST, "%s%d%s%d-%d-%dT%d:%d:%d.000+02:00%s", initialString, average_temp, middlestring, timeinfo.tm_year+1900, timeinfo.tm_mon+1, timeinfo.tm_mday, timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec ,finalString);
+
+        ESP_LOGI(TAG, "%s", REQUEST);
+
+
+        if (write(s, REQUEST, strlen(REQUEST)) < 0) {
+            ESP_LOGE(TAG, "... socket send failed");
+            close(s);
+            vTaskDelay(4000 / portTICK_PERIOD_MS);
+            continue;
+        }
+        ESP_LOGI(TAG, "... socket send success");
+
+        struct timeval receiving_timeout;
+        receiving_timeout.tv_sec = 5;
+        receiving_timeout.tv_usec = 0;
+        r = setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &receiving_timeout, sizeof(receiving_timeout));
+        if ( r < 0) {
+            ESP_LOGE(TAG, "... failed to set socket receiving timeout");
+            close(s);
+            vTaskDelay(4000 / portTICK_PERIOD_MS);
+            continue;
+        }
+        ESP_LOGI(TAG, "... set socket receiving timeout success");
+
+        /* Read HTTP response */
+        do {
+            bzero(recv_buf, sizeof(recv_buf));
+            r = read(s, recv_buf, sizeof(recv_buf)-1);
+            for(int i = 0; i < r; i++) {
+            	 putchar(recv_buf[i]);
+            }
+        } while(r > 0);
+
+        ESP_LOGI(TAG, "... done reading from socket. Last read return=%d errno=%d\r\n", r, errno);
+        close(s);
+        for(int countdown = 10; countdown >= 0; countdown--) {
+            ESP_LOGI(TAG, "%d... ", countdown);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
+        }
+        ESP_LOGI(TAG, "Starting again!");
+    }
+}
+
+
+
+
+
+static void initialize_sntp(void)
+{
+    ESP_LOGI(TAG, "Initializing SNTP");
+    sntp_setoperatingmode(SNTP_OPMODE_POLL);
+    sntp_setservername(0, "pool.ntp.org");
+    sntp_init();
+}
+
+void get_data( void * parameter)
+{
+  int counter = 0;
+  float temp;
+  float sum = 0;
+  while(1){
+	  counter += 1;
+	  temp = (temprature_sens_read()- 32) / 1.8; 			// convert temperature from F' to C'
+	  //printf("ESP32 core Temperature = %f\n", temp);
+
+      vTaskDelay(3000 / portTICK_PERIOD_MS);
+      sum += temp;
+      if(counter == 10){
+    	  average_temp = sum/10;
+    	  sum = 0;
+    	  counter = 0;
+    	  printf("Task 2::  updated the average core Temperature: %d\n", average_temp);
+      }
+  }
+}
+
+
+static void obtain_time(void)
+{
+	initialise_wifi();
+    xEventGroupWaitBits(wifi_event_group, CONNECTED_BIT,
+                        false, true, portMAX_DELAY);
+    initialize_sntp();
+
+
+    // wait for time to be set
+    time_t now = 0;
+    struct tm timeinfo = { 0 };
+    int retry = 0;
+    const int retry_count = 10;
+    while(timeinfo.tm_year < (2019 - 1900) && ++retry < retry_count) {
+    	ESP_LOGI(TAG, "year: %d", timeinfo.tm_year);
+        ESP_LOGI(TAG, "Waiting for system time to be set... (%d/%d)", retry, retry_count);
+        vTaskDelay(2000 / portTICK_PERIOD_MS);
+        time(&now);
+        localtime_r(&now, &timeinfo);
+    }
+
+    // ESP_ERROR_CHECK( esp_wifi_stop() );
+}
+
+
+void app_main()
+{
+    ESP_ERROR_CHECK( nvs_flash_init() );
+
+
+    xTaskCreate(&http_get_task, "http_get_task", 4096, NULL, 1, NULL);
+    xTaskCreate(&get_data, "get_data", 10000, NULL, 2, NULL);
+
+}