In this project you’re going to build an ESP8266 Wi-Fi Button that can trigger any home automation event. This is like a remote control that you can take in your pocket or place anywhere that when pressed sends out an email. It can also be called a DIY Amazon Dash Button clone.

Prerequisites

Before proceeding with this tutorial we recommend taking a look at these resources:

Getting Started with ESP8266 Wi-Fi

ESP8266 Deep Sleep with Arduino IDE

ESP8266 Voltage Regulator (LiPo and Li-ion Batteries)

If you like ESP8266 and you want to learn more about it. I recommend downloading my course: Home Automation using ESP8266.

Introduction

The Wi-Fi button is not a new idea and this concept was popularized by Amazon that created the Dash button, which is a small button that instantly orders a product to your home.

Instead of ordering a product we can turn on a light, toggle a lamp, send a value, trigger an email notification and much more, as you’re going to see by the end of this project.

IFTTT

For this project we’re going to use a free service called IFTTT that stands for If This Than That.

This service is used to automate a wide variety of tasks online. In this case, we will send an email when the ESP pushbutton is pressed.

Type in your browser https://ifttt.com and click the “Get started” button in the middle of the page. Complete the form with your details and create your account.

Creating the Applet

Open the “My Applets” tab, press the create “New Applet” button.

Click the “This” word and search for the “Webhooks” service.

Receive a web request

You need to type in the event name button_pressed. With the Webhooks service you can trigger an action when you make an HTTP request to a specific URL.

Click the “Create trigger” button:

Now press the “That” word and search for the Gmail service.

Send email

If it’s the first time using the Gmail service with IFTTT, a new window opens and you’ll have to grant access, so IFTTT can send out emails through your account.

Choose the “Send email” option and enter the email address in the “To address” field where you want to receive your notification.

You can customize the subject and body of the email, but for demonstration purposes I’ll leave the default values. Finally press the “Create action” button.

You should have your Applet created after clicking “Finish”

:

Testing the Applet

Open the “Search” tab, find the Webhooks service and open it.

Go to the “Documentation” tab.

Here you can find your unique API KEY that you must keep private. Type in the event name, button_pressed. Your final URL should appear in the bottom of the web page. Copy that URL.

Open a new tab in your browser and hit enter. You should see this message saying “Congratulations!”.

Open your email client and the new message should be there.

In case the email didn’t arrive after a few seconds, I recommend double-checking the URL and see if you’re using the correct event name, both in your Applet and in your URL.

Note: if it worked save your unique URL in a Notepad, because you’ll need it later in this project.

code

#include <ESP8266WiFi.h>

// Replace with your SSID and Password

const char* ssid = "REPLACE_WITH_YOUR_SSID";

const char* password = "REPLACE_WITH_YOUR_PASSWORD";

// Replace with your unique IFTTT URL resource

const char* resource = "REPLACE_WITH_YOUR_IFTTT_URL_RESOURCE";

// How your resource variable should look like, but with your own API KEY (that API KEY below is just an example):

//const char* resource = "/trigger/button_pressed/with/key/nAZjOphL3d-ZO4N3k64-1A7gTlNSrxMJdmqy";

// Maker Webhooks IFTTT

const char* server = "maker.ifttt.com";

void setup() {

Serial.begin(115200);

initWifi();

makeIFTTTRequest();

// Deep sleep mode until RESET pin is connected to a LOW signal (pushbutton is pressed)

ESP.deepSleep(0);

}

void loop() {

// sleeping so wont get here

}

// Establish a Wi-Fi connection with your router

void initWifi() {

Serial.print("Connecting to: ");

Serial.print(ssid);

WiFi.begin(ssid, password);

int timeout = 10 * 4; // 10 seconds

while(WiFi.status() != WL_CONNECTED && (timeout-- > 0)) {

delay(250);

Serial.print(".");

}

Serial.println("");

if(WiFi.status() != WL_CONNECTED) {

Serial.println("Failed to connect, going back to sleep");

}

Serial.print("WiFi connected in: ");

Serial.print(millis());

Serial.print(", IP address: ");

Serial.println(WiFi.localIP());

}

// Make an HTTP request to the IFTTT web service

void makeIFTTTRequest() {

Serial.print("Connecting to ");

Serial.print(server);

WiFiClient client;

int retries = 5;

while(!!!client.connect(server, 80) && (retries-- > 0)) {

Serial.print(".");

}

Serial.println();

if(!!!client.connected()) {

Serial.println("Failed to connect, going back to sleep");

}

Serial.print("Request resource: ");

Serial.println(resource);

client.print(String("GET ") + resource +

" HTTP/1.1\r\n" +

"Host: " + server + "\r\n" +

"Connection: close\r\n\r\n");

int timeout = 5 * 10; // 5 seconds

while(!!!client.available() && (timeout-- > 0)){

delay(100);

}

if(!!!client.available()) {

Serial.println("No response, going back to sleep");

}

while(client.available()){

Serial.write(client.read());

}

Serial.println("\nclosing connection");

client.stop();

}