In this tutorial, we are going to learn how to use the ESP32 to detect water leaks and send real-time notifications via email. This step-by-step tutorial covers sensor setup, code examples, and integration with email services, ensuring your home or office is protected from potential water damage. Perfect for DIY enthusiasts and smart home developers looking to enhance their water leak detection systems.
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Introduction to Water Sensor and Gmail
We have specific tutorials about Water Sensor and Gmail. Each tutorial contains detailed information and step-by-step instructions about hardware pinout, working principle, wiring connection to ESP32, ESP32 code... Learn more about them at the following links:
/* * This ESP32 code is created by esp32io.com * * This ESP32 code is released in the public domain * * For more detail (instruction and wiring diagram), visit https://esp32io.com/tutorials/esp32-water-leak-email-notification */#include <WiFi.h>#include <ESP_Mail_Client.h>#define WIFI_SSID "YOUR_WIFI_SSID"// CHANGE IT#define WIFI_PASSWORD "YOUR_WIFI_PASSWORD"// CHANGE IT// the sender email credentials#define SENDER_EMAIL "xxxxxx@gmail.com"// CHANGE IT#define SENDER_PASSWORD "xxxx xxxx xxxx xxxx"// CHANGE IT to your Google App password#define RECIPIENT_EMAIL "xxxxxx@gmail.com"// CHANGE IT#define SMTP_HOST "smtp.gmail.com"#define SMTP_PORT 587#define WATER_SENSOR_PIN 19 // ESP32 pin GPIO19 connected to water sensor's pinint water_state; // current state of water sensorint prev_water_state; // previous state of water sensorSMTPSessionsmtp;voidsetup() {Serial.begin(9600);WiFi.begin(WIFI_SSID, WIFI_PASSWORD);Serial.print("Connecting to Wi-Fi");while (WiFi.status() != WL_CONNECTED) {Serial.print(".");delay(300); }Serial.println();Serial.print("Connected with IP: ");Serial.println(WiFi.localIP());Serial.println();pinMode(WATER_SENSOR_PIN, INPUT_PULLUP); // set ESP32 pin to input pull-up mode water_state = digitalRead(WATER_SENSOR_PIN); // read state}voidloop() { prev_water_state = water_state; // save the last state water_state = digitalRead(WATER_SENSOR_PIN); // read new stateif (prev_water_state == HIGH && water_state == LOW) {Serial.println("Water leakage is detected!");String subject = "Email Notification from ESP32";String textMsg = "This is an email sent from ESP32.\n"; textMsg += "Water leakage is detected"; gmail_send(subject, textMsg); }}void gmail_send(String subject, String textMsg) {// set the network reconnection optionMailClient.networkReconnect(true);smtp.debug(1);smtp.callback(smtpCallback); Session_Config config;// set the session configconfig.server.host_name = SMTP_HOST;config.server.port = SMTP_PORT;config.login.email = SENDER_EMAIL;config.login.password = SENDER_PASSWORD;config.login.user_domain = F("127.0.0.1");config.time.ntp_server = F("pool.ntp.org,time.nist.gov");config.time.gmt_offset = 3;config.time.day_light_offset = 0;// declare the message class SMTP_Message message;// set the message headers message.sender.name = F("ESP32"); message.sender.email = SENDER_EMAIL; message.subject = subject; message.addRecipient(F("To Whom It May Concern"), RECIPIENT_EMAIL); message.text.content = textMsg; message.text.transfer_encoding = "base64"; message.text.charSet = F("utf-8"); message.priority = esp_mail_smtp_priority::esp_mail_smtp_priority_low;// set the custom message header message.addHeader(F("Message-ID: <abcde.fghij@gmail.com>"));// connect to the serverif (!smtp.connect(&config)) {Serial.printf("Connection error, Status Code: %d, Error Code: %d, Reason: %s\n", smtp.statusCode(), smtp.errorCode(), smtp.errorReason().c_str());return; }if (!smtp.isLoggedIn()) {Serial.println("Not yet logged in."); } else {if (smtp.isAuthenticated())Serial.println("Successfully logged in.");elseSerial.println("Connected with no Auth."); }// start sending Email and close the sessionif (!MailClient.sendMail(&smtp, &message))Serial.printf("Error, Status Code: %d, Error Code: %d, Reason: %s\n", smtp.statusCode(), smtp.errorCode(), smtp.errorReason().c_str());}// callback function to get the Email sending statusvoid smtpCallback(SMTP_Status status) {// print the current statusSerial.println(status.info());// print the sending resultif (status.success()) {Serial.println("----------------");Serial.printf("Email sent success: %d\n", status.completedCount());Serial.printf("Email sent failed: %d\n", status.failedCount());Serial.println("----------------\n");for (size_t i = 0; i < smtp.sendingResult.size(); i++) {// get the result item SMTP_Result result = smtp.sendingResult.getItem(i);Serial.printf("Message No: %d\n", i + 1);Serial.printf("Status: %s\n", result.completed ? "success" : "failed");Serial.printf("Date/Time: %s\n", MailClient.Time.getDateTimeString(result.timestamp, "%B %d, %Y %H:%M:%S").c_str());Serial.printf("Recipient: %s\n", result.recipients.c_str());Serial.printf("Subject: %s\n", result.subject.c_str()); }Serial.println("----------------\n");// free the memorysmtp.sendingResult.clear(); }}
Install the water sensor on the place that can encounter with water leak
Connect the ESP32 board to the water sensor
Connect the ESP32 board to your PC via a micro USB cable
Open Arduino IDE on your PC.
Select the right ESP32 board (e.g. ESP32 Dev Module) and COM port.
Open the Library Manager by clicking on the Library Manager icon on the left navigation bar of Arduino IDE.
Search ESP Mail Client, then find the ESP Mail Client created by Mobizt.
Click Install button to install ESP Mail Client library.
Copy the above code and open with Arduino IDE
Change the WiFi information (SSID and password) in the code to yours by changing two contanst WIFI_SSID and WIFI_PASSWORD
Change the sender email and password in the code to yours by changing two contanst SENDER_EMAIL and SENDER_PASSWORD
Change the recipient email in the code to yours by changing two contanst RECIPIENT_EMAIL. recipient email can be the same as sender
※ NOTE THAT:
Sender email MUST be Gmail
Sender password is the App passwords you got from previous step
Recipient email can be any type of email
Click Upload button on Arduino IDE to upload code to ESP32
Open the Serial Monitor
Pour some water to the water sensor
Check out the result on Serial Monitor.
Newbiely | Arduino IDE 2.3.8
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ESP32 Dev Module
Newbiely.ino
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8Serial.println("Hello World!");
Output
Serial Monitor
Message (Enter to send message to 'ESP32 Dev Module' on 'COM15')
New Line
9600 baud
Water leakage is detected
#### Email sent successfully
> C: Email sent successfully
----------------
Message sent success: 1
Message sent failed: 0
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Message No: 1
Status: success
Date/Time: May 27, 2024 04:42:50
Recipient: xxxxxx@gmail.com
Subject: Email Notification from ESP32
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Ln 11, Col 1
ESP32 Dev Module on COM15
2
Check your recipient email box. You will get an email as below:
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