Basic example for sending data to Ubidots using ESP8266 based devices

ESP8266_Ubidots.cpp

/*************************************************************************************************
 * This Example sends harcoded data to Ubidots and serves as example for users that has devices
 * based on ESP8266 chips that we don't support with a library.
 * 
 * This example is given AS IT IS without any warranty
 * 
 * Made by Jose García.
 *************************************************************************************************/



/********************************
 * Libraries included
 *******************************/

#include <ESP8266WiFi.h>

/********************************
 * Constants and objects
 *******************************/

char const * SSID_NAME = "...."; // Put here your SSID name
char const * SSID_PASS = "...."; // Put here your password
char const * HTTPSERVER = "things.ubidots.com";
int HTTPPORT = 80;

/* Keep in mind that for robust operation you should avoid to use String variables */
String TOKEN = "...."; // Put here your TOKEN
String VAR_ID = "59132fc976254212a50eb4dc"; // Your variable ID
String USER_AGENT = "ESP8266";
String VERSION = "1.0";

WiFiClient clientUbi;

/********************************
 * Auxiliar Functions
 *******************************/


/********************************
 * Main Functions
 *******************************/

void setup() {
  Serial.begin(115200);
  
  /* Connects to AP */
  WiFi.begin(SSID_NAME, SSID_PASS);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
    }

  WiFi.setAutoReconnect(true);
  Serial.println(F("WiFi connected"));
  Serial.println(F("IP address: "));
  Serial.println(WiFi.localIP());

}

void loop() {

  /* Keep in mind that for robust operation you should avoid to use String variables */

  /* Adapt your value array following the structure specified at https://ubidots.com/docs/api/index.html#send-values-to-one-variable */
  float sensor_value = random(0, 1000)*1.0;
  String str_value = String(sensor_value, 4);
  
  String value = "[{\"variable\":\""
                  + VAR_ID
                  + "\",\"value\":" 
                  + str_value
                  +"}]";

  int i = value.length();
  
  String postString = "POST /api/v1.6/collections/values/?force=true HTTP/1.1\r\n"
                    "Host: things.ubidots.com\r\n"
                    "User-Agent:" + USER_AGENT + "/" + VERSION + "\r\n"
                    "X-Auth-Token: " + TOKEN + "\r\n"
                    "Connection: close\r\n"
                    "Content-Type: application/json\r\n"
                    "Content-Length: " + String(i) + "\r\n"
                    "\r\n"
                    + value +
                    "\r\n";

  clientUbi.connect(HTTPSERVER, HTTPPORT);

  if (clientUbi.connect(HTTPSERVER, HTTPPORT)) {
        Serial.println(F("Posting your variables: "));
        Serial.println(postString);
        clientUbi.print(postString);
  }

  while (clientUbi.available()) {
        char c = clientUbi.read();
        Serial.write(c);
  }

  clientUbi.stop();
  delay(5000);
}