DHT11 + ESP8266 Thingspeak

#include <DHT.h>

#include <ESP8266WiFi.h>

// replace with your channel’s thingspeak API key,
 String apiKey = "xxxxxxxxxxxxx";
 const char* ssid = "xxxxxxxxx";
 const char* password = "xxxxxxx";

const char* server = "api.thingspeak.com";
#define DHTPIN 2 // what pin we’re connected to

DHT dht(DHTPIN, DHT11,15);
 WiFiClient client;

void setup() {
 Serial.begin(115200);
 delay(10);
 dht.begin();

WiFi.begin(ssid, password);

Serial.println();
 Serial.println();
 Serial.print("Connecting to ");
 Serial.println(ssid);

WiFi.begin(ssid, password);

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

}

void loop() {

float h = dht.readHumidity();
 float t = dht.readTemperature();
 if (isnan(h) || isnan(t)) {
 Serial.println("Failed to read from DHT sensor!");
 return;
 }

if (client.connect(server,80)) { // "184.106.153.149" or api.thingspeak.com
 String postStr = apiKey;
 postStr +="&field1=";
 postStr += String(t);
 postStr +="&field2=";
 postStr += String(h);
 postStr += "\r\n\r\n";

client.print("POST /update HTTP/1.1\n");
 client.print("Host: api.thingspeak.com\n");
 client.print("Connection: close\n");
 client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
 client.print("Content-Type: application/x-www-form-urlencoded\n");
 client.print("Content-Length: ");
 client.print(postStr.length());
 client.print("\n\n");
 client.print(postStr);

Serial.print("Temperature: ");
 Serial.print(t);
 Serial.print(" degrees Celcius Humidity: ");
 Serial.print(h);
 Serial.println("% send to Thingspeak");
 }
 client.stop();

Serial.println("Waiting…");
 // thingspeak needs minimum 15 sec delay between updates
 delay(15000);
 }