Dallas sensor to ThingSpeak on ESP8266 Arduino

/* Code snippet to use Dallas sensor with ThingSpeak
 * Use lib Arduino manager to install ThingSpeak and DallasTemperature libraries
 */

#include "ThingSpeak.h"
#include <ESP8266WiFi.h>
#include <OneWire.h>
#include <DallasTemperature.h>

...
/*============ Dallas device setup ==================*/
// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature tempSensor(&oneWire);

const int MAX_DEVICES = 3;
static int nDeviceCount = 0;
static DeviceAddress tempDev[MAX_DEVICES];

static void findDeviceAddr(void)
{
    tempSensor.begin();
    nDeviceCount = tempSensor.getDeviceCount();

    if (nDeviceCount > MAX_DEVICES)
        nDeviceCount = MAX_DEVICES;

    for (int i=0; i < nDeviceCount; i++)
    {
        uint8_t *devAddr = tempDev[i];
        if (tempSensor.getAddress(devAddr,i))
            Serial.println("getAddress ok");
    }
}
static float getTempF( DeviceAddress deviceAddress)
{
    float tempF = DallasTemperature::toFahrenheit( tempSensor.getTempC(deviceAddress));
    return tempF;
}

...
/*============ ThingSpeak setup ==================*/
// Note:  Each channel has its own number and write API key
// API key is what get used - wrong channel number doesn't matter

static unsigned long myChannelNumber = YOUR_CHANNEL_NUMBER; // Customize
static const char   *myWriteAPIKey = "Your API KEY";        // Customize
...

/*== Global client for ThingSpeak */
static WiFiClient  client;

static void sampleTemperature()
{
    // request to all devices on the bus
    tempSensor.requestTemperatures(); // Send the command to get temperatures

    for (int i=0; i < nDeviceCount; i++)
    {
        float tempF = getTempF(tempDev[i]);
        Serial.print(String(i+1)+": "+tempF+"F ");
        ThingSpeak.setField( i+1, tempF);
    }
    Serial.println();
    if (nDeviceCount > 0)
    {
        int rc = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
        Serial.println(String("Post rc=")+rc);
    }
}


void setup ()
{
    Serial.begin(115200);

    /* Must Do Wifi setup first... */
...
    /* Wifi should be ready after this */
...
    ThingSpeak.begin(client);   // initialize ThingSpeak lib
...
    findDeviceAddr();   // locate OneWire devices on the bus
...
}

void loop ()
{
...
            if (itsTimeToSample)
                sampleTemperature();
...
}