esp32 add new file

mqtt-client-ESP32/README.md

@@ -0,0 +1,34 @@
+# ESP32 MQTT Client Examples
+
+In this example we provide sample code for TCP protocol connection to the MQTT Broker. For more documentation on using the ESP32 MQTT client, see the [Pubsubclient Documentation](https://pubsubclient.knolleary.net/).
+
+## Prerequisites
+
+* Arduino ESP32 development board management address: https://dl.espressif.com/dl/package_esp32_index.json
+
+## Arduino settings
+
+* Installing the ESP32 Board
+
+```
+Tools -> Board -> Boards Manager... -> -> Type ESP32 in Search field -> Install
+```
+
+* Installing the PubSubClient Library
+
+```bash
+Sketch -> Include Library -> Manage Libraries... -> Type PubSubClient in Search field -> Install PubSubClient by Nick O’Leary
+```
+
+## Ino File
+
+* esp32_connect_mqtt.ino: ESP32 connects to the MQTT broker
+* esp32_connect_mqtt_via_tls.ino: ESP32 connects to the MQTT broker via TLS
+* esp32_DS18B20_temp_chart: ESP32 connects to the MQTT broker and uploads DS18B20 temperature sensor data, while displaying the temperature chart in real time
+* esp32_DS18B20_sensor_via_tls.ino: ESP32 connects to the MQTT broker via TLS and uploads DS18B20 temperature sensor data
+* esp32_soil_moisture_sensor_via_tls.ino: ESP32 connects to the MQTT broker via TLS and uploads soil moisture sensor data
+
+## TLS Config
+
+For TLS connection example code, the default includes DigiCert Global Root G2 (broker.emqx.io.crt) and DigiCert Global Root CA (emqxsl-ca.crt) ca_cert certificates, please modify according to the usage scenario.
+

mqtt-client-ESP32/README_ZH.md

@@ -0,0 +1,37 @@
+# ESP32 MQTT 客户端使用示例
+
+在本示例中我们提供了 TCP 协议连接到 MQTT Broker 示例代码。 有关 ESP32 MQTT 客户端更多使用文档，请参阅 [PubSubClient 官方文档](https://pubsubclient.knolleary.net/)。
+
+## 前提
+
+* Arduino ESP32 开发板管理地址: https://dl.espressif.com/dl/package_esp32_index.json
+
+## Arduino 设置
+
+* 安装 ESP32 开发板
+
+```
+点击 工具 -> 开发板 -> 开发板管理 -> 搜索 ESP32 -> 点击安装
+```
+
+* 安装 PubSub client
+
+```
+项目 -> 加载库 -> 管理库... -> 搜索 PubSubClient -> 安装 PubSubClient by Nick O’Leary
+```
+
+## 文件
+
+* esp32_connect_mqtt.ino: ESP32 连接到 MQTT 服务器
+* esp32_connect_mqtt_via_tls.ino: ESP32 通过 TLS 连接到 MQTT 服务器
+* esp32_DS18B20_temp_chart: ESP32 通过 MQTT 连接到服务器并上传 DS18B20 温度传感器数据，同时实时显示温度图表
+* esp32_DS18B20_sensor_via_tls.ino: ESP32 通过 TLS 连接到 MQTT 服务器并上传 DS18B20 温度传感器数据
+* esp32_soil_moisture_sensor_via_tls.ino: ESP32 通过 TLS 连接到 MQTT 服务器并上传土壤湿度传感器数据
+
+## TLS 配置
+
+对于 TLS 连接示例代码，默认包含了 DigiCert Global Root G2 (broker.emqx.io-ca.crt) 和 DigiCert Global Root CA (emqxsl-ca.crt) ca_cert 证书，请依据使用场景自行修改。
+
+
+
+

mqtt-client-ESP32/broker.emqx.io-ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
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+MrY=
+-----END CERTIFICATE-----

mqtt-client-ESP32/emqxsl-ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
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+-----END CERTIFICATE-----

mqtt-client-ESP32/esp32_DS18B20_sensor_via_tls.ino

@@ -0,0 +1,165 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <WiFiClientSecure.h>
+#include <ArduinoJson.h>
+#include <OneWire.h>
+#include <DallasTemperature.h>
+
+// WiFi credentials
+const char *ssid = "WIFI_SSID";             // Replace with your WiFi name
+const char *password = "WIFI_PASSWORD";   // Replace with your WiFi password
+
+// MQTT Broker configuration
+const char *mqtt_broker = "broker.emqx.io";
+const char *mqtt_topic = "emqx/esp32/telemetry";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 8883;
+
+// WiFi and MQTT client initialization
+WiFiClientSecure esp_client;
+PubSubClient mqtt_client(esp_client);
+
+// Root CA Certificate
+// Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+const char *ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
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+MrY=
+-----END CERTIFICATE-----
+)EOF";
+
+// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+/*
+const char* ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
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+-----END CERTIFICATE-----
+*/
+
+// GPIO pin for DS18B20
+const int one_wire_bus = 25;
+
+// Temperature Sensor Setup
+OneWire oneWire(one_wire_bus);
+DallasTemperature sensors(&oneWire);
+DeviceAddress inside_thermometer;
+
+
+// Function Declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void initializeSensors();
+
+float readTemperature();
+
+void publishTemperature(float temperature);
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    connectToMQTT();
+    initializeSensors();
+}
+
+void connectToWiFi() {
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to WiFi");
+}
+
+void connectToMQTT() {
+    esp_client.setCACert(ca_cert);
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setKeepAlive(60);
+
+    while (!mqtt_client.connected()) {
+        String client_id = "esp32-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s...\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT Broker");
+        } else {
+            Serial.print("Failed to connect, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" Retrying in 5 seconds.");
+            delay(5000);
+        }
+    }
+}
+
+void initializeSensors() {
+    sensors.begin();
+    if (!sensors.getAddress(inside_thermometer, 0)) {
+        Serial.println("Unable to find address for Device 0");
+    }
+    sensors.setResolution(inside_thermometer, 12);
+}
+
+float readTemperature() {
+    sensors.requestTemperatures();
+    return sensors.getTempC(inside_thermometer);
+}
+
+void publishTemperature(float temperature) {
+    StaticJsonDocument<200> json_doc;
+    json_doc["temp"] = temperature;
+
+    char json_buffer[512];
+    serializeJson(json_doc, json_buffer);
+    mqtt_client.publish(mqtt_topic, json_buffer);
+}
+
+
+void loop() {
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+
+    float temp_celsius = readTemperature();
+    publishTemperature(temp_celsius);
+    delay(60000); // Delay between readings
+}

mqtt-client-ESP32/esp32_DS18B20_temp_chart/.gitignore

@@ -0,0 +1,9 @@
+*.pyc
+
+venv/
+.idea/
+__pycache__/
+article/
+
+*.db
+

mqtt-client-ESP32/esp32_DS18B20_temp_chart/README.md

@@ -0,0 +1,102 @@
+# ESP32 Temperature Monitoring and Web Application Project
+
+This project consists of two main parts: an ESP32 device sending temperature data using MQTT and a Flask-based web application that displays this data.
+
+![webui.png](_assets/webui.png)
+
+## Part 1: ESP32 Temperature Monitoring
+
+### Requirements
+
+- ESP32 Development Board
+- DS18B20 Temperature Sensor
+- Arduino IDE with ESP32 support
+- Wi-Fi connection
+
+### Configuration and Setup
+
+1. **Install the Arduino IDE**:
+   Download and install from [Arduino website](https://www.arduino.cc/en/software).
+
+2. **Add ESP32 Support in Arduino IDE**:
+   Follow the instructions [here](https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/).
+
+3. **Install Required Libraries**:
+   In Arduino IDE, go to `Sketch` > `Include Library` > `Manage Libraries...` and install:
+    - `WiFi`
+    - `PubSubClient`
+    - `ArduinoJson`
+    - `OneWire`
+    - `DallasTemperature`
+
+4. **Configure Wi-Fi and MQTT Settings**:
+   Modify the provided ESP32 code in Arduino IDE with your Wi-Fi and MQTT details.
+
+5. **Connect the DS18B20 Sensor to ESP32**:
+    - DS18B20 VCC to ESP32 3.3V
+    - DS18B20 GND to ESP32 GND
+    - DS18B20 Data to ESP32 GPIO 25
+      ![esp32](./_assets/esp32.png)
+
+6. **Upload the Code**:
+   Connect ESP32 to your computer, select the correct board and port in Arduino IDE, and upload.
+
+## Part 2: Flask Web Application
+
+### Requirements
+
+- Python 3.8 or later
+- Virtual environment tool (e.g., `virtualenv`)
+
+### Local Setup
+
+1. **Clone the Repository**:
+   ```
+   git clone [Repository URL]
+   cd [Repository Name]
+   ```
+
+2. **Create a Virtual Environment**:
+   ```
+   python -m venv venv
+   source venv/bin/activate  # Windows: venv\Scripts\activate
+   ```
+
+3. **Install Dependencies**:
+   ```
+   pip install -r requirements.txt
+   ```
+
+4. **Configure MQTT Settings in `app.py`**:
+   Modify MQTT configuration in `app.py`.
+
+5. **Run the Application**:
+   ```
+   python app.py
+   ```
+   Access at `http://localhost:8080`.
+
+### Deploying to Fly.io
+
+1. **Install Fly.io CLI**:
+   Follow instructions on [Fly.io documentation](https://fly.io/docs/getting-started/installing-flyctl/).
+
+2. **Login to Fly.io**:
+   ```
+   flyctl auth login
+   ```
+
+3. **Initialize Fly.io App**:
+   ```
+   flyctl launch
+   ```
+
+4. **Deploy the App**:
+   ```
+   flyctl deploy
+   ```
+
+5. **Verify Deployment**:
+   ```
+   flyctl status
+   ```

mqtt-client-ESP32/esp32_DS18B20_temp_chart/README_ZH.md

@@ -0,0 +1,107 @@
+# ESP32 温度监控及 Web 应用项目
+
+该项目包括两个主要部分：使用 MQTT 发送温度数据的 ESP32 设备和一个用于显示这些数据的基于 Flask 的 Web 应用程序。
+
+![webui.png](_assets/webui.png)
+
+## 第 1 部分：ESP32 温度监控
+
+### 系统要求
+
+- ESP32 开发板
+- DS18B20 温度传感器
+- 支持 ESP32 的 Arduino IDE
+- Wi-Fi 连接
+
+### 配置和设置
+
+1. **安装 Arduino IDE**：
+   从 [Arduino 网站](https://www.arduino.cc/en/software) 下载并安装。
+
+2. **在 Arduino IDE 中添加 ESP32 支持**：
+   按照[这里](https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/)的说明操作。
+
+3. **安装所需的库**：
+   在 Arduino IDE 中，转到 `Sketch` > `Include Library` > `Manage Libraries...` 并安装：
+    - `WiFi`
+    - `PubSubClient`
+    - `ArduinoJson`
+    - `OneWire`
+    - `DallasTemperature`
+
+4. **配置 Wi-Fi 和 MQTT 设置**：
+   在 Arduino IDE 中用您的 Wi-Fi 和 MQTT 详细信息修改提供的 ESP32 代码。
+
+5. **将 DS18B20 传感器连接到 ESP32**：
+    - DS18B20 VCC 接 ESP32 3.3V
+    
+    - DS18B20 GND 接 ESP32 GND
+    
+    - DS18B20 数据接 ESP32 GPIO 25
+    
+      ![esp32](./_assets/esp32.png)
+    
+
+6. **上传代码**：
+   将 ESP32 连接到计算机，在 Arduino IDE 中选择正确的板和端口，然后上传。
+
+## 第 2 部分：Flask Web 应用程序
+
+### 系统要求
+
+- Python 3.8 或更高版本
+- 虚拟环境工具（如 `virtualenv`）
+
+### 本地设置
+
+1. **克隆仓库**：
+   ```
+   git clone [仓库 URL]
+   cd [仓库名称]
+   ```
+
+2. **创建虚拟环境**：
+   ```
+   python -m venv venv
+   source venv/bin/activate  # Windows: venv\Scripts\activate
+   ```
+
+3. **安装依赖**：
+   ```
+   pip install -r requirements.txt
+   ```
+
+4. **在 `app.py` 中配置 MQTT 设置**：
+   修改 `app.py` 中的 MQTT 配置。
+
+5. **运行应用程序**：
+   ```
+   python app.py
+   ```
+   在 `http://localhost:8080` 访问。
+
+### 部署到 Fly.io
+
+1. **安装 Fly.io CLI**：
+   按照 [Fly.io 文档](https://fly.io/docs/getting-started/installing-flyctl/) 中的说明进行操作。
+
+2. **登录 Fly.io**：
+   
+   ```
+   flyctl auth login
+   ```
+   
+3. **初始化 Fly.io 应用**：
+   ```
+   flyctl launch
+   ```
+
+4. **部署应用程序**：
+   ```
+   flyctl deploy
+   ```
+
+5. **验证部署**：
+   ```
+   flyctl status
+   ```

mqtt-client-ESP32/esp32_DS18B20_temp_chart/esp32/README.md

@@ -0,0 +1,48 @@
+# ESP32 Temperature Monitoring Project
+
+This project involves an ESP32 device using MQTT to send temperature data. The ESP32 is configured with a DS18B20 temperature sensor and connects to an MQTT broker.
+
+### Requirements
+
+- ESP32 Development Board
+- DS18B20 Temperature Sensor
+- Arduino IDE with ESP32 support
+- Wi-Fi connection
+
+### Configuration and Setup
+
+1. **Install the Arduino IDE**:
+   Download and install the Arduino IDE from [Arduino website](https://www.arduino.cc/en/software).
+
+2. **Add ESP32 Support in Arduino IDE**:
+   Follow the instructions [here](https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/) to add ESP32 board support to the Arduino IDE.
+
+3. **Install Required Libraries**:
+   Open the Arduino IDE, go to `Sketch` > `Include Library` > `Manage Libraries...`. Install the following libraries:
+   - `WiFi`
+   - `PubSubClient`
+   - `ArduinoJson`
+   - `OneWire`
+   - `DallasTemperature`
+
+4. **Configure Wi-Fi and MQTT Settings**:
+   Open the provided ESP32 code in Arduino IDE. Modify the following lines with your Wi-Fi and MQTT broker details:
+   ```cpp
+   const char* wifi_ssid = "your_wifi_ssid";
+   const char* wifi_password = "your_wifi_password";
+   const char* mqtt_broker = "your_mqtt_broker";
+   const char* mqtt_username = "your_mqtt_username";
+   const char* mqtt_password = "your_mqtt_password";
+   ```
+
+5. **Connect the DS18B20 Sensor to ESP32**:
+   Connect the DS18B20 sensor to your ESP32:
+   - DS18B20 VCC to ESP32 3.3V
+   - DS18B20 GND to ESP32 GND
+   - DS18B20 Data to ESP32 GPIO 25 (or change `one_wire_bus` in the code if using a different pin)
+
+6. **Upload the Code**:
+   Connect the ESP32 to your computer, select the correct board and port in Arduino IDE, and upload the code.
+
+7. **Monitor the Temperature Data**:
+   Once the code is uploaded, the ESP32 will start sending temperature data to the MQTT broker.

mqtt-client-ESP32/esp32_DS18B20_temp_chart/esp32/README_ZH.md

@@ -0,0 +1,51 @@
+# ESP32 温度监控项目
+
+此项目涉及使用 MQTT 发送温度数据的 ESP32 设备。ESP32 配置了 DS18B20 温度传感器，并连接到 MQTT 代理。
+
+### 系统要求
+
+- ESP32 开发板
+- DS18B20 温度传感器
+- Arduino IDE 并支持 ESP32
+- Wi-Fi 连接
+
+### 配置和设置
+
+1. **安装 Arduino IDE**：
+   从 [Arduino 网站](https://www.arduino.cc/en/software) 下载并安装 Arduino IDE。
+
+2. **在 Arduino IDE 中添加 ESP32 支持**：
+   按照[这里](https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/)的说明，将 ESP32 板支持添加到 Arduino IDE。
+
+3. **安装所需的库**：
+   打开 Arduino IDE，转到 `Sketch` > `Include Library` > `Manage Libraries...`。安装以下库：
+
+   - `WiFi`
+   - `PubSubClient`
+   - `ArduinoJson`
+   - `OneWire`
+   - `DallasTemperature`
+
+4. **配置 Wi-Fi 和 MQTT 设置**：
+   在 Arduino IDE 中打开提供的 ESP32 代码。用您的 Wi-Fi 和 MQTT 代理详细信息修改以下行：
+
+   ```cpp
+   const char* wifi_ssid = "your_wifi_ssid";
+   const char* wifi_password = "your_wifi_password";
+   const char* mqtt_broker = "your_mqtt_broker";
+   const char* mqtt_username = "your_mqtt_username";
+   const char* mqtt_password = "your_mqtt_password";
+   ```
+
+5. **将 DS18B20 传感器连接到 ESP32**：
+   将 DS18B20 传感器连接到您的 ESP32：
+
+   - DS18B20 VCC 接 ESP32 3.3V
+   - DS18B20 GND 接 ESP32 GND
+   - DS18B20 数据接 ESP32 GPIO 25（如果使用不 同的引脚，请更改代码中的 `one_wire_bus`）
+
+6. **上传代码**：
+   将 ESP32 连接到您的计算机，在 Arduino IDE 中选择正确的板和端口，然后上传代码。
+
+7. **监控温度数据**：
+   代码上传后，ESP32 将开始向 MQTT 代理发送温度数据。

mqtt-client-ESP32/esp32_DS18B20_temp_chart/esp32/water_temperature_sensor.ino

@@ -0,0 +1,165 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <WiFiClientSecure.h>
+#include <ArduinoJson.h>
+#include <OneWire.h>
+#include <DallasTemperature.h>
+
+// WiFi credentials
+const char *ssid = "WIFI_SSID";             // Replace with your WiFi name
+const char *password = "WIFI_PASSWORD";   // Replace with your WiFi password
+
+// MQTT Broker configuration
+const char *mqtt_broker = "broker.emqx.io";
+const char *mqtt_topic = "emqx/esp32/telemetry";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 8883;
+
+// WiFi and MQTT client initialization
+WiFiClientSecure esp_client;
+PubSubClient mqtt_client(esp_client);
+
+// Root CA Certificate
+// Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+const char *ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+)EOF";
+
+// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+/*
+const char* ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+*/
+
+// GPIO pin for DS18B20
+const int one_wire_bus = 25;
+
+// Temperature Sensor Setup
+OneWire oneWire(one_wire_bus);
+DallasTemperature sensors(&oneWire);
+DeviceAddress inside_thermometer;
+
+
+// Function Declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void initializeSensors();
+
+float readTemperature();
+
+void publishTemperature(float temperature);
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    connectToMQTT();
+    initializeSensors();
+}
+
+void connectToWiFi() {
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to WiFi");
+}
+
+void connectToMQTT() {
+    esp_client.setCACert(ca_cert);
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setKeepAlive(60);
+
+    while (!mqtt_client.connected()) {
+        String client_id = "esp32-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s...\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT Broker");
+        } else {
+            Serial.print("Failed to connect, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" Retrying in 5 seconds.");
+            delay(5000);
+        }
+    }
+}
+
+void initializeSensors() {
+    sensors.begin();
+    if (!sensors.getAddress(inside_thermometer, 0)) {
+        Serial.println("Unable to find address for Device 0");
+    }
+    sensors.setResolution(inside_thermometer, 12);
+}
+
+float readTemperature() {
+    sensors.requestTemperatures();
+    return sensors.getTempC(inside_thermometer);
+}
+
+void publishTemperature(float temperature) {
+    StaticJsonDocument<200> json_doc;
+    json_doc["temp"] = temperature;
+
+    char json_buffer[512];
+    serializeJson(json_doc, json_buffer);
+    mqtt_client.publish(mqtt_topic, json_buffer);
+}
+
+
+void loop() {
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+
+    float temp_celsius = readTemperature();
+    publishTemperature(temp_celsius);
+    delay(60000); // Delay between readings
+}

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/.dockerignore

@@ -0,0 +1,15 @@
+# flyctl launch added from .idea/.gitignore
+# Default ignored files
+.idea/
+
+# flyctl launch added from venv/.gitignore
+# created by virtualenv automatically
+venv/**/*
+
+fly.toml
+
+./data/database.db
+
+./__pycache__/
+
+

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/Dockerfile

@@ -0,0 +1,11 @@
+FROM python:3.8-slim-buster
+
+WORKDIR /app
+
+COPY . /app
+
+RUN pip install --no-cache-dir -r requirements.txt
+
+EXPOSE 8080
+
+CMD ["python", "app.py"]

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/FLY_README.md

@@ -0,0 +1,54 @@
+Based on the provided `fly.toml` configuration file, here's a deployment guide for your `esp32-temp-chart` application on Fly.io. This guide assumes that you have already developed a Flask application that is ready to be deployed.
+
+### Prerequisites
+
+1. **Fly.io Account**: Ensure you have a Fly.io account. If not, sign up at [Fly.io](https://fly.io/).
+2. **Fly CLI**: Install the Fly CLI tool. Instructions can be found on the [Fly.io documentation](https://fly.io/docs/hands-on/installing/).
+3. **Docker**: Your application must be containerized with Docker. Install Docker if it's not already installed.
+4. **Local Application Code**: Have your Flask application code ready on your local machine.
+
+### Step-by-Step Deployment Guide
+
+#### 1. Initialize Your Fly.io Application
+
+- Navigate to your project directory in the terminal.
+- Run `flyctl apps create esp32-temp-chart`. This command creates a new application on Fly.io with the name specified in your `fly.toml` file.
+
+#### 2. Configure the `fly.toml` File
+
+- Place your `fly.toml` file in the root of your project directory.
+- Review the `fly.toml` file to ensure all configurations are correct. Particularly, check the `app` name, `primary_region`, and the `http_service` configurations.
+
+#### 3. Set Up Docker
+
+- Create a `Dockerfile` in your project root. This file should contain instructions to build a Docker image for your Flask application.
+- Ensure that your application listens on the port specified in `fly.toml` (8080 in this case).
+
+#### 4. Test Your Docker Container Locally (Optional)
+
+- Build your Docker image: `docker build -t esp32-temp-chart .`
+- Run your container locally to ensure it works: `docker run --rm -p 8080:8080 esp32-temp-chart`
+- Test the local deployment by navigating to `http://localhost:8080`.
+
+#### 5. Deploy Your Application
+
+- From your project directory, run `flyctl deploy`. This command will build your application's Docker image and deploy it to Fly.io.
+- Monitor the deployment process in your terminal to ensure it completes successfully.
+
+#### 6. Verify the Deployment
+
+- Once deployed, you can access your application using the URL provided by Fly.io.
+- Test the `/ping` endpoint to ensure your application responds correctly.
+
+#### 7. Monitoring and Management
+
+- Use `flyctl logs` to view real-time logs from your application.
+- Use `flyctl status` to check the status of your application.
+- To scale your application, use `flyctl scale count <number_of_instances>`.
+
+### Additional Notes
+
+- The `[[mounts]]` section in `fly.toml` is used to persist data. Ensure the `source` and `destination` are correctly set for your application's data needs.
+- The `[checks]` section defines health checks for your application. Adjust the `path`, `interval`, and `headers` as needed for your application's health endpoint.
+
+Remember, always test your application locally before deploying to ensure it's working as expected. If you encounter issues, the Fly.io documentation and community forums are great resources for troubleshooting.

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/README.md

@@ -0,0 +1,68 @@
+# ESP32 Temperature Chart Web Application
+
+This Flask-based web application displays temperature data sent from an ESP32 device using MQTT. It includes a web interface for visualizing the temperature chart and an API to fetch temperature data.
+
+### Requirements
+
+- Python 3.8 or later
+- Virtual environment tool (like `virtualenv` or `conda`)
+- MQTT Broker credentials
+
+### Local Setup
+
+1. **Clone the Repository:**
+   ```
+   git clone [Repository URL]
+   cd [Repository Name]
+   ```
+
+2. **Create a Virtual Environment:**
+   ```
+   python -m venv venv
+   source venv/bin/activate  # On Windows: venv\Scripts\activate
+   ```
+
+3. **Install Dependencies:**
+   ```
+   pip install -r requirements.txt
+   ```
+
+4. **Configure MQTT Settings in `app.py`:**
+   Modify the MQTT configuration settings in `app.py`:
+   - `MQTT_BROKER_URL`
+   - `MQTT_BROKER_PORT`
+   - `MQTT_USERNAME`
+   - `MQTT_PASSWORD`
+   - `MQTT_CLIENT_ID`
+
+5. **Run the Application:**
+   ```
+   python app.py
+   ```
+   Access the web interface at `http://localhost:8080`.
+
+### Deploying to Fly.io
+
+1. **Install Fly.io CLI:**
+   Follow the instructions on [Fly.io documentation](https://fly.io/docs/getting-started/installing-flyctl/).
+
+2. **Login to Fly.io:**
+   ```
+   flyctl auth login
+   ```
+
+3. **Initialize Fly.io App:**
+   ```
+   flyctl launch
+   ```
+
+4. **Deploy the App:**
+   ```
+   flyctl deploy
+   ```
+
+5. **Verify Deployment:**
+   ```
+   flyctl status
+   ```
+   Visit the URL provided by Fly.io to access your application.

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/README_ZH.md

@@ -0,0 +1,79 @@
+# ESP32 温度图表 Web 应用程序
+
+这个基于 Flask 的 Web 应用程序用于显示通过 MQTT 从 ESP32 设备发送的温度数据。它包括一个用于可视化温度图表的 Web 界面和一个获取温度数据的 API。
+
+### 系统要求
+
+- Python 3.8 或更高版本
+- 虚拟环境工具（如 `virtualenv` 或 `conda`）
+- MQTT 代理凭证
+
+### 本地设置
+
+1. **克隆仓库：**
+
+   ```
+   git clone [仓库 URL]
+   cd [仓库名称]
+   ```
+
+2. **创建虚拟环境：**
+
+   ```
+   python -m venv venv
+   source venv/bin/activate  # Windows 上: venv\Scripts\activate
+   ```
+
+3. **安装依赖：**
+
+   ```
+   pip install -r requirements.txt
+   ```
+
+4. **在 `app.py` 中配置 MQTT 设置：**
+   修改 `app.py` 中的 MQTT 配置设置：
+
+    - `MQTT_BROKER_URL`
+    - `MQTT_BROKER_PORT`
+    - `MQTT_USERNAME`
+    - `MQTT_PASSWORD`
+    - `MQTT_CLIENT_ID`
+
+5. **运行应用程序：**
+
+   ```
+   python app.py
+   ```
+
+   在 `http://localhost:8080` 访问 Web 界面。
+
+### 部署到 Fly.io
+
+1. **安装 Fly.io CLI：**
+   按照 [Fly.io 文档](https://fly.io/docs/getting-started/installing-flyctl/) 中的说明进行操作。
+
+2. **登录 Fly.io：**
+
+   ```
+   flyctl auth login
+   ```
+
+3. **初始化 Fly.io 应用：**
+
+   ```
+   flyctl launch
+   ```
+
+4. **部署应用程序：**
+
+   ```
+   flyctl deploy
+   ```
+
+5. **验证部署：**
+
+   ```
+   flyctl status
+   ```
+
+   访问 Fly.io 提供的 URL 以访问您的应用程序。

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/__init__.py

@@ -0,0 +1 @@
+# coding: utf-8

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/app.py

@@ -0,0 +1,143 @@
+import datetime
+import json
+import logging
+import os
+import ssl
+import random
+import sqlite3
+from typing import Dict, Any, List, Optional
+
+import requests
+from flask import Flask, jsonify, render_template, g, request
+from flask_mqtt import Mqtt
+
+
+# Configure logging
+logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
+
+app = Flask(__name__)
+
+DEBUG: bool = False
+MQTT_CLIENT: Optional[Mqtt] = None
+DATABASE: str = './data/database.db'
+SLACK_WEBHOOK: str = 'https://hooks.slack.com/services'
+MQTT_TOPIC: str = 'emqx/esp32/telemetry'
+app.config['MQTT_BROKER_URL'] = 'broker.emqx.io'
+app.config['MQTT_BROKER_PORT'] = 8883
+app.config['MQTT_USERNAME'] = ''
+app.config['MQTT_PASSWORD'] = ''
+app.config['MQTT_KEEPALIVE'] = 60
+app.config['MQTT_CLIENT_ID'] = f"flask-mqtt-{random.randint(0, 100000)}"
+app.config['MQTT_TLS_ENABLED'] = True
+# Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+app.config['MQTT_TLS_CA_CERTS'] = './certs/broker.emqx.io-ca.crt'
+# Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+# app.config['MQTT_TLS_CA_CERTS'] = './certs/emqxsl-ca.crt'
+app.config['MQTT_TLS_VERSION'] = ssl.PROTOCOL_TLSv1_2
+app.config['MQTT_RECONNECT_DELAY'] = 3
+
+
+def init_mqtt(flask_app: Flask) -> None:
+    global MQTT_CLIENT
+    MQTT_CLIENT = Mqtt(flask_app)
+
+    @MQTT_CLIENT.on_connect()
+    def handle_connect(client, userdata, flags, rc):
+        client_id = flask_app.config['MQTT_CLIENT_ID']
+        mqtt_broker = flask_app.config['MQTT_BROKER_URL']
+        if rc == 0:
+            logging.info(f"Client {client_id} connected to {mqtt_broker}!")
+            MQTT_CLIENT.subscribe(MQTT_TOPIC)
+        else:
+            logging.error(f"Failed to connect, return code {rc}")
+
+    @MQTT_CLIENT.on_message()
+    def handle_mqtt_message(client, userdata, message) -> None:
+        try:
+            payload: Dict[str, Any] = json.loads(message.payload.decode())
+            temp: float = payload['temp']
+        except (json.JSONDecodeError, KeyError, TypeError) as e:
+            logging.error(f"Error processing message: {e}")
+            return
+        if temp > 25:
+            logging.warning("Temperature too high, sending alert to Slack!")
+            requests.post(
+                SLACK_WEBHOOK,
+                data=json.dumps({'text': f"Temperature too high: {temp}"}),
+                headers={'Content-Type': 'application/json'}
+            )
+        uptime: str = datetime.datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S")
+        logging.info(f"Received message: {temp} at {uptime}")
+        with app.app_context():
+            db = get_db()
+            db.execute(
+                "INSERT INTO temperature_data (uptime, temp) VALUES (?, ?)",
+                (uptime, temp)
+            )
+            db.commit()
+
+
+def get_db() -> sqlite3.Connection:
+    db: sqlite3.Connection = getattr(g, '_database', None)
+    if db is None:
+        db = g._database = sqlite3.connect(DATABASE)
+    return db
+
+
+@app.teardown_appcontext
+def close_connection(exception) -> None:
+    db = getattr(g, '_database', None)
+    if db is not None:
+        db.close()
+
+
+@app.route('/')
+def index():
+    redirect_url = request.url_root + 'temp_chart'
+    return f"<a href='{redirect_url}'>Go to Temperature chart 😁</a>"
+
+
+@app.route('/ping')
+def ping():
+    return "pong"
+
+
+@app.route('/temp_chart')
+def chart():
+    return render_template('chart.html')
+
+
+@app.route('/data')
+def data():
+    hours: int = int(request.args.get('hours', 1, type=int))
+    if hours > 24 or hours < 1:
+        hours = 1
+
+    db = get_db()
+    min_time: datetime.datetime = datetime.datetime.utcnow() - datetime.timedelta(hours=hours)
+    cursor = db.execute(
+        "SELECT * FROM temperature_data WHERE uptime > ?",
+        (min_time.strftime("%Y-%m-%d %H:%M:%S"),)
+    )
+    rows = cursor.fetchall()
+    times: List[str] = [row[1] for row in rows]
+    temperatures: List[float] = [row[2] for row in rows]
+    return jsonify({"times": times, "temperatures": temperatures})
+
+
+if __name__ == '__main__':
+
+    with app.app_context():
+        d = get_db()
+        d.execute(
+            "CREATE TABLE IF NOT EXISTS "
+            "temperature_data (id INTEGER PRIMARY KEY, uptime TEXT, temp REAL)"
+        )
+        d.commit()
+    if DEBUG:
+        if os.environ.get('WERKZEUG_RUN_MAIN') == 'true':
+            init_mqtt(app)
+    else:
+        init_mqtt(app)
+
+    app.run(host='0.0.0.0', debug=DEBUG, port=8080)

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/certs/broker.emqx.io-ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----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+BgNVHRMBAf8EBTADAQH/MA4GA1UdDwEB/wQEAwIBhjAdBgNVHQ4EFgQUTiJUIBiV
+5uNu5g/6+rkS7QYXjzkwDQYJKoZIhvcNAQELBQADggEBAGBnKJRvDkhj6zHd6mcY
+1Yl9PMWLSn/pvtsrF9+wX3N3KjITOYFnQoQj8kVnNeyIv/iPsGEMNKSuIEyExtv4
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+Fdtom/DzMNU+MeKNhJ7jitralj41E6Vf8PlwUHBHQRFXGU7Aj64GxJUTFy8bJZ91
+8rGOmaFvE7FBcf6IKshPECBV1/MUReXgRPTqh5Uykw7+U0b6LJ3/iyK5S9kJRaTe
+pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
+MrY=
+-----END CERTIFICATE-----

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/certs/emqxsl-ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----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+hMAtudXH/vTBH1jLuG2cenTnmCmrEbXjcKChzUyImZOMkXDiqw8cvpOp/2PV5Adg
+06O/nVsJ8dWO41P0jmP6P6fbtGbfYmbW0W5BjfIttep3Sp+dWOIrWcBAI+0tKIJF
+PnlUkiaY4IBIqDfv8NZ5YBberOgOzW6sRBc4L0na4UU+Krk2U886UAb3LujEV0ls
+YSEY1QSteDwsOoBrp+uvFRTp2InBuThs4pFsiv9kuXclVzDAGySj4dzp30d8tbQk
+CAUw7C29C79Fv1C5qfPrmAESrciIxpg0X40KPMbp1ZWVbd4=
+-----END CERTIFICATE-----

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/fly.toml

@@ -0,0 +1,34 @@
+# fly.toml app configuration file generated for esp32-temp-chart on 2023-08-18T10:04:07+08:00
+#
+# See https://fly.io/docs/reference/configuration/ for information about how to use this file.
+#
+
+app = "esp32-temp-chart"
+primary_region = "sin"
+
+[build]
+
+[[mounts]]
+  source = "esp32tempchart"
+  destination = "/app/data"
+
+[http_service]
+  internal_port = 8080
+  force_https = true
+  auto_stop_machines = false
+  auto_start_machines = true
+  min_machines_running = 1
+  processes = ["app"]
+
+[checks]
+  [checks.name_of_your_http_check]
+    port = 8080
+    type = "http"
+    interval = "15s"
+    timeout = "10s"
+    grace_period = "30s"
+    method = "get"
+    path = "/ping"
+    [checks.name_of_your_http_check.headers]
+      Authorization = "super-secret"
+      Content-Type = "application/json"

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/requirements.txt

@@ -0,0 +1,3 @@
+Flask==2.3.2
+Flask-MQTT==1.1.1
+requests==2.31.0

mqtt-client-ESP32/esp32_DS18B20_temp_chart/web/templates/chart.html

@@ -0,0 +1,64 @@
+<!doctype html>
+<html>
+
+<head>
+  <title>Temperature Chart</title>
+  <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
+  <meta http-equiv="refresh" content="60">
+</head>
+
+<body>
+<select id="hours" onchange="fetchData()">
+  <option value="1" selected>Last 1 hour</option>
+  <option value="12">Last 12 hours</option>
+  <option value="24">Last 24 hours</option>
+</select>
+<canvas id="chart"></canvas>
+<script>
+    const ctx = document.getElementById('chart').getContext('2d');
+    const hoursSelect = document.getElementById('hours');
+    const chart = new Chart(ctx, {
+        type: 'line',
+        data: {
+            labels: [],
+            datasets: [{
+                label: 'Temperature',
+                data: [],
+                fill: false,
+                borderColor: 'rgb(75, 192, 192)',
+                tension: 0.1
+            }]
+        },
+        options: {
+            scales: {
+                x: {
+                    title: {
+                        display: true,
+                        text: 'Time (UTC)'
+                    }
+                },
+                y: {
+                    title: {
+                        display: true,
+                        text: 'Temperature'
+                    }
+                }
+            }
+        }
+    });
+
+    async function fetchData() {
+        const hours = hoursSelect.value;
+        const response = await fetch(`/data?hours=${hours}`);
+        const data = await response.json();
+        chart.data.labels = data.times.map(time => new Date(time).toLocaleString());
+        chart.data.datasets[0].data = data.temperatures;
+        chart.update();
+    }
+
+    fetchData();
+    setInterval(fetchData, 60000);
+</script>
+</body>
+
+</html>

mqtt-client-ESP32/esp32_connect_mqtt.ino/esp32_connect_mqtt.ino.ino

@@ -0,0 +1,101 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+
+// WiFi Credentials
+const char *ssid = "rehome";            // Replace with your WiFi name
+const char *password = "Ruihong123";  // Replace with your WiFi password
+
+// MQTT Broker Settings
+const char *mqtt_broker = "mqtt.fileview123.com";
+const char *mqtt_topic = "/device/esp8266/+";
+const char *mqtt_username = "admin";
+const char *mqtt_password = "publish452131wW452131wW$";
+const int mqtt_port = 1883;
+const char *mqtt_topic_publish = "/device/esp8266/status";     // MQTT topic publish
+
+WiFiClient espClient;
+PubSubClient mqtt_client(espClient);
+
+// Function Declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void mqttCallback(char *mqtt_topic, byte *payload, unsigned int length);
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setKeepAlive(60);
+    mqtt_client.setCallback(mqttCallback); // Corrected callback function name
+    connectToMQTT();
+}
+
+void connectToWiFi() {
+    delay(10);
+    Serial.println();
+    Serial.print("正在连接: ");
+    Serial.println(ssid);
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to WiFi");
+    Serial.println("");
+    Serial.println("WiFi 连接成功");
+    Serial.println("IP 地址: ");
+    Serial.println(WiFi.localIP());
+}
+
+void connectToMQTT() {
+    while (!mqtt_client.connected()) {
+        Serial.print("尝试 MQTT 连接...");
+        String client_id = "esp32-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s.....\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("连接成功");
+            Serial.println("Connected to MQTT broker");
+            mqtt_client.subscribe(mqtt_topic);
+            mqtt_client.publish(mqtt_topic_publish, "Hi EMQX I'm ESP32 ^^"); // Publish message upon successful connection
+        } else {
+            Serial.print("Failed, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" try again in 5 seconds");
+            delay(5000);
+        }
+    }
+}
+
+void mqttCallback(char *mqtt_topic, byte *payload, unsigned int length) {
+    Serial.print("Message received on mqtt_topic: ");
+    Serial.println(mqtt_topic);
+    Serial.print("Message: ");
+    for (unsigned int i = 0; i < length; i++) {
+        Serial.print((char) payload[i]);
+    }
+    Serial.println("\n-----------------------");
+}
+
+
+void loop() {
+    if(WiFi.status() != WL_CONNECTED){
+        connectToWiFi();
+    }
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+    // 发布消息示例
+  static unsigned long lastMsg = 0;
+  if (millis() - lastMsg > 5000) {
+    lastMsg = millis();
+    
+    String message = "Hello from esp32 - esp32_connect_mqtt.ino_" + String(millis());
+    mqtt_client.publish(mqtt_topic_publish, message.c_str());
+    
+    Serial.println("消息已发布: " + message);
+  }
+}

mqtt-client-ESP32/esp32_connect_mqtt_via_tls.ino

@@ -0,0 +1,139 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <WiFiClientSecure.h>
+
+// WiFi credentials
+const char *ssid = "WIFI_SSID";             // Replace with your WiFi name
+const char *password = "WIFI_PASSWORD";   // Replace with your WiFi password
+
+// MQTT Broker settings
+const char *mqtt_broker = "broker.emqx.io";
+const char *mqtt_topic = "emqx/esp32";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 8883;
+
+// WiFi and MQTT client initialization
+WiFiClientSecure esp_client;
+PubSubClient mqtt_client(esp_client);
+
+// Root CA Certificate
+// Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+const char *ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
+d3cuZGlnaWNlcnQuY29tMSAwHgYDVQQDExdEaWdpQ2VydCBHbG9iYWwgUm9vdCBH
+MjAeFw0xMzA4MDExMjAwMDBaFw0zODAxMTUxMjAwMDBaMGExCzAJBgNVBAYTAlVT
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+q2EGnI/yuum06ZIya7XzV+hdG82MHauVBJVJ8zUtluNJbd134/tJS7SsVQepj5Wz
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+pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
+MrY=
+-----END CERTIFICATE-----
+)EOF";
+
+// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+/*
+const char* ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
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+9w0BAQEFAAOCAQ8AMIIBCgKCAQEA4jvhEXLeqKTTo1eqUKKPC3eQyaKl7hLOllsB
+CSDMAZOnTjC3U/dDxGkAV53ijSLdhwZAAIEJzs4bg7/fzTtxRuLWZscFs3YnFo97
+nh6Vfe63SKMI2tavegw5BmV/Sl0fvBf4q77uKNd0f3p4mVmFaG5cIzJLv07A6Fpt
+43C/dxC//AH2hdmoRBBYMql1GNXRor5H4idq9Joz+EkIYIvUX7Q6hL+hqkpMfT7P
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+CAUw7C29C79Fv1C5qfPrmAESrciIxpg0X40KPMbp1ZWVbd4=
+-----END CERTIFICATE-----
+*/
+
+
+// Function Declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void mqttCallback(char *topic, byte *payload, unsigned int length);
+
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+
+    // Set Root CA certificate
+    esp_client.setCACert(ca_cert);
+
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setKeepAlive(60);
+    mqtt_client.setCallback(mqttCallback);
+    connectToMQTT();
+}
+
+void connectToWiFi() {
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to WiFi");
+}
+
+void connectToMQTT() {
+    while (!mqtt_client.connected()) {
+        String client_id = "esp32-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s...\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT broker");
+            mqtt_client.subscribe(mqtt_topic);
+            mqtt_client.publish(mqtt_topic, "Hi EMQX I'm ESP32 ^^");  // Publish message upon connection
+        } else {
+            Serial.print("Failed to connect to MQTT broker, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" Retrying in 5 seconds.");
+            delay(5000);
+        }
+    }
+}
+
+void mqttCallback(char *topic, byte *payload, unsigned int length) {
+    Serial.print("Message received on topic: ");
+    Serial.println(topic);
+    Serial.print("Message: ");
+    for (unsigned int i = 0; i < length; i++) {
+        Serial.print((char) payload[i]);
+    }
+    Serial.println("\n-----------------------");
+}
+
+
+void loop() {
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+}

mqtt-client-ESP32/esp32_soil_moisture_sensor_via_tls.ino

@@ -0,0 +1,144 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <WiFiClientSecure.h>
+#include <ArduinoJson.h>
+
+// WiFi credentials
+const char *ssid = "WIFI_SSID"; // Replace with your WiFi name
+const char *password = "WIFI_PASSWORD"; // Replace with your WiFi password
+
+// MQTT Broker configuration
+const char *mqtt_broker = "broker.emqx.io";
+const char *mqtt_topic = "emqx/esp32/moisture";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 8883;
+
+// WiFi and MQTT client initialization
+WiFiClientSecure esp_client;
+PubSubClient mqtt_client(esp_client);
+
+// GPIO pin for Soil Moisture, ESP32 pin GPIO36 (ADC0) that connects to AOUT pin of moisture sensor
+#define sensorPIN 36
+
+// Root CA Certificate
+// Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+const char *ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
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+pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
+MrY=
+-----END CERTIFICATE-----
+)EOF";
+
+// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+/*
+const char* ca_cert = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
+MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
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+CAUw7C29C79Fv1C5qfPrmAESrciIxpg0X40KPMbp1ZWVbd4=
+-----END CERTIFICATE-----
+*/
+
+
+// Function Declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void initializeSensors();
+
+void publishSensorData();
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    connectToMQTT();
+}
+
+void connectToWiFi() {
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to WiFi");
+}
+
+void connectToMQTT() {
+    esp_client.setCACert(ca_cert);
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setKeepAlive(60);
+
+    while (!mqtt_client.connected()) {
+        String client_id = "esp32-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s...\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT Broker");
+        } else {
+            Serial.print("Failed to connect, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" Retrying in 5 seconds.");
+            delay(5000);
+        }
+    }
+}
+
+
+void publishSensorData() {
+    StaticJsonDocument<200> json_doc;
+    int moistureValue = analogRead(sensorPIN);
+    json_doc["moisture"] = moistureValue;
+
+    char json_buffer[512];
+    serializeJson(json_doc, json_buffer);
+    mqtt_client.publish(mqtt_topic, json_buffer);
+    Serial.printf("Published to %s: %d\n", mqtt_topic, moistureValue);
+}
+
+
+void loop() {
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+
+    publishSensorData();
+    delay(60000); // Delay between readings
+}

mqtt-client-ESP8266/README.md

@@ -0,0 +1,23 @@
+# ESP8266 MQTT Client Examples
+In this example we provide sample code for TCP protocol connection to the MQTT Broker.
+For more documentation on using the ESP8266 MQTT client, see the [ESP8266 pubsubclient Documentation](https://pubsubclient.knolleary.net/).
+
+## Prerequisites
+* Arduino ESP8266 development board management address: http://arduino.esp8266.com/stable/package_esp8266com_index.json
+
+
+## Installation
+```bash
+Sketch -> Include Library -> Manage Libraries... -> Type PubSub in Search field -> Install
+```
+
+## Ino File
+* esp_connect_mqtt.ino: ESP8266 connects to the MQTT broker
+* esp_mqtt_led.ino: ESP8266 control led
+* temp_hum.ino: getting started with the ESP8266 and DHT11 sensor 
+* esp_mqtt_moisture.ino: Soil Moisture Sensor example  
+
+
+## Other
+* [ESP8266 connects to the free public MQTT broker](https://www.emqx.io/blog/esp8266-connects-to-the-public-mqtt-broker)
+* [Upload sensor data to MQTT cloud service via ESP8266](https://www.emqx.io/blog/upload-sensor-data-to-mqtt-cloud-service-via-nodemcu-esp8266)

mqtt-client-ESP8266/README_ZH.md

@@ -0,0 +1,26 @@
+# ESP8266 MQTT 客户端使用示例
+在本示例中我们提供了 TCP 协议连接到 MQTT Broker 示例代码。
+有关 ESP8266 MQTT 客户端更多使用文档，请参阅 [ESP8266 MQTT 官方文档](https://pubsubclient.knolleary.net/)。
+
+
+## 前提
+* Arduino ESP8266 开发板管理地址: http://arduino.esp8266.com/stable/package_esp8266com_index.json
+
+
+## 安装
+```
+Sketch -> Include Library -> Manage Libraries... -> Type PubSub in Search field -> Install
+```
+
+## 文件
+* esp_connect_mqtt.ino: ESP8266 连接到 MQTT 服务器
+* esp_mqtt_led.ino: ESP8266 远程控制 LED 灯
+* temp_hum.ino: ESP8266 上报温湿度数据
+
+## 参阅
+* [ESP8266 连接到 MQTT 服务器](https://www.emqx.cn/blog/esp8266-connects-to-the-public-mqtt-broker)
+* [ESP8266 远程控制 LED 灯](https://www.emqx.cn/blog/esp8266_mqtt_led)
+* [ESP8266 上报温湿度数据](https://www.emqx.cn/blog/upload-sensor-data-to-mqtt-cloud-service-via-nodemcu-esp8266)
+
+
+

mqtt-client-ESP8266/broker.emqx.io-ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
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+MrY=
+-----END CERTIFICATE-----

mqtt-client-ESP8266/emqxsl-ca.crt

@@ -0,0 +1,22 @@
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+MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
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+-----END CERTIFICATE-----

mqtt-client-ESP8266/esp8266_connect_mqtt_via_tls/esp8266_connect_mqtt_via_tls.ino

@@ -0,0 +1,166 @@
+#include <ESP8266WiFi.h>
+#include <PubSubClient.h>
+#include <time.h>
+
+// WiFi credentials
+const char *ssid = "WIFI_SSID";             // Replace with your WiFi name
+const char *password = "WIFI_PASSWORD";   // Replace with your WiFi password
+
+// MQTT Broker settings
+const int mqtt_port = 8883;  // MQTT port (TLS)
+const char *mqtt_broker = "broker.emqx.io";  // EMQX broker endpoint
+const char *mqtt_topic = "emqx/esp8266";     // MQTT topic
+const char *mqtt_username = "emqx";  // MQTT username for authentication
+const char *mqtt_password = "public";  // MQTT password for authentication
+
+// NTP Server settings
+const char *ntp_server = "pool.ntp.org";     // Default NTP server
+// const char* ntp_server = "cn.pool.ntp.org"; // Recommended NTP server for users in China
+const long gmt_offset_sec = 0;            // GMT offset in seconds (adjust for your time zone)
+const int daylight_offset_sec = 0;        // Daylight saving time offset in seconds
+
+// WiFi and MQTT client initialization
+BearSSL::WiFiClientSecure espClient;
+PubSubClient mqtt_client(espClient);
+
+// SSL certificate for MQTT broker
+// Load DigiCert Global Root G2, which is used by EMQX Public Broker: broker.emqx.io
+static const char ca_cert[]
+PROGMEM = R"EOF(
+-----BEGIN CERTIFICATE-----
+MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
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+1x7e/dfgy5SDN67sH0NO3Xss0r0upS/kqbitOtSZpLYl6ZtrAGCSYP9PIUkY92eQ
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+vIOlCsRnKPZzFBQ9RnbDhxSJITRNrw9FDKZJobq7nMWxM4MphQIDAQABo0IwQDAP
+BgNVHRMBAf8EBTADAQH/MA4GA1UdDwEB/wQEAwIBhjAdBgNVHQ4EFgQUTiJUIBiV
+5uNu5g/6+rkS7QYXjzkwDQYJKoZIhvcNAQELBQADggEBAGBnKJRvDkhj6zHd6mcY
+1Yl9PMWLSn/pvtsrF9+wX3N3KjITOYFnQoQj8kVnNeyIv/iPsGEMNKSuIEyExtv4
+NeF22d+mQrvHRAiGfzZ0JFrabA0UWTW98kndth/Jsw1HKj2ZL7tcu7XUIOGZX1NG
+Fdtom/DzMNU+MeKNhJ7jitralj41E6Vf8PlwUHBHQRFXGU7Aj64GxJUTFy8bJZ91
+8rGOmaFvE7FBcf6IKshPECBV1/MUReXgRPTqh5Uykw7+U0b6LJ3/iyK5S9kJRaTe
+pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
+MrY=
+-----END CERTIFICATE-----
+)EOF";
+
+// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment
+/*
+static const char ca_cert[] PROGMEM = R"EOF(
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+)EOF";
+*/
+
+
+// Function declarations
+void connectToWiFi();
+
+void connectToMQTT();
+
+void syncTime();
+
+void mqttCallback(char *topic, byte *payload, unsigned int length);
+
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    syncTime();  // X.509 validation requires synchronization time
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setCallback(mqttCallback);
+    connectToMQTT();
+}
+
+void connectToWiFi() {
+    WiFi.begin(ssid, password);
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(1000);
+        Serial.println("Connecting to WiFi...");
+    }
+    Serial.println("Connected to WiFi");
+}
+
+void syncTime() {
+    configTime(gmt_offset_sec, daylight_offset_sec, ntp_server);
+    Serial.print("Waiting for NTP time sync: ");
+    while (time(nullptr) < 8 * 3600 * 2) {
+        delay(1000);
+        Serial.print(".");
+    }
+    Serial.println("Time synchronized");
+    struct tm timeinfo;
+    if (getLocalTime(&timeinfo)) {
+        Serial.print("Current time: ");
+        Serial.println(asctime(&timeinfo));
+    } else {
+        Serial.println("Failed to obtain local time");
+    }
+}
+
+void connectToMQTT() {
+    BearSSL::X509List serverTrustedCA(ca_cert);
+    espClient.setTrustAnchors(&serverTrustedCA);
+    while (!mqtt_client.connected()) {
+        String client_id = "esp8266-client-" + String(WiFi.macAddress());
+        Serial.printf("Connecting to MQTT Broker as %s.....\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT broker");
+            mqtt_client.subscribe(mqtt_topic);
+            // Publish message upon successful connection
+            mqtt_client.publish(mqtt_topic, "Hi EMQX I'm ESP8266 ^^");
+        } else {
+            char err_buf[128];
+            espClient.getLastSSLError(err_buf, sizeof(err_buf));
+            Serial.print("Failed to connect to MQTT broker, rc=");
+            Serial.println(mqtt_client.state());
+            Serial.print("SSL error: ");
+            Serial.println(err_buf);
+            delay(5000);
+        }
+    }
+}
+
+void mqttCallback(char *topic, byte *payload, unsigned int length) {
+    Serial.print("Message received on topic: ");
+    Serial.print(topic);
+    Serial.print("]: ");
+    for (int i = 0; i < length; i++) {
+        Serial.print((char) payload[i]);
+    }
+    Serial.println();
+}
+
+void loop() {
+    if (!mqtt_client.connected()) {
+        connectToMQTT();
+    }
+    mqtt_client.loop();
+}

mqtt-client-ESP8266/esp_connect_mqtt/esp_connect_mqtt.ino

@@ -0,0 +1,105 @@
+//安装mqtt客户端 PubSubClient 库
+
+#include <ESP8266WiFi.h>
+#include <PubSubClient.h>
+
+// WiFi settings
+const char *ssid = "rehome";             // Replace with your WiFi name
+const char *password = "Ruihong123";   // Replace with your WiFi password
+
+// MQTT Broker settings
+const char *mqtt_broker = "mqtt.fileview123.com";  // EMQX broker endpoint
+const char *mqtt_topic = "/device/esp8266/+";     // MQTT topic
+const char *mqtt_username = "admin";  // MQTT username for authentication
+const char *mqtt_password = "publish452131wW452131wW$";  // MQTT password for authentication
+const int mqtt_port = 1883;  // MQTT port (TCP)
+const char *mqtt_topic_publish = "/device/esp8266/status";     // MQTT topic publish
+
+WiFiClient espClient;
+PubSubClient mqtt_client(espClient);
+
+void connectToWiFi();
+
+void connectToMQTTBroker();
+
+void mqttCallback(char *topic, byte *payload, unsigned int length);
+
+void setup() {
+    Serial.begin(115200);
+    connectToWiFi();
+    mqtt_client.setServer(mqtt_broker, mqtt_port);
+    mqtt_client.setCallback(mqttCallback);
+    connectToMQTTBroker();
+}
+
+void connectToWiFi() {
+    delay(10);
+    Serial.println();
+    Serial.print("正在连接: ");
+    Serial.println(ssid);
+    WiFi.begin(ssid, password);
+    Serial.print("Connecting to WiFi");
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.print(".");
+    }
+    Serial.println("\nConnected to the WiFi network");
+    Serial.println("");
+    Serial.println("WiFi 连接成功");
+    Serial.println("IP 地址: ");
+    Serial.println(WiFi.localIP());
+}
+
+void connectToMQTTBroker() {
+    while (!mqtt_client.connected()) {
+        Serial.print("尝试 MQTT 连接...");
+        //String client_id = "esp8266-client-" + String(WiFi.macAddress());
+        String client_id = "esp8266-client-";
+        client_id += String(random(0xffff), HEX);
+        Serial.printf("Connecting to MQTT Broker as %s.....\n", client_id.c_str());
+        if (mqtt_client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Connected to MQTT broker");
+            Serial.println("连接成功");
+            mqtt_client.subscribe(mqtt_topic);
+            // Publish message upon successful connection
+            //mqtt_client.publish(mqtt_topic, "Hi EMQX I'm ESP8266 ^^");
+        } else {
+            Serial.print("Failed to connect to MQTT broker, rc=");
+            Serial.print(mqtt_client.state());
+            Serial.println(" try again in 5 seconds");
+            delay(5000);
+        }
+    }
+}
+
+void mqttCallback(char *topic, byte *payload, unsigned int length) {
+    Serial.print("Message received on topic: ");
+    Serial.println(topic);
+    Serial.print("Message:");
+    for (unsigned int i = 0; i < length; i++) {
+        Serial.print((char) payload[i]);
+    }
+    Serial.println();
+    Serial.println("-----------------------");
+}
+
+void loop() {
+    if(WiFi.status() != WL_CONNECTED){
+        connectToWiFi();
+    }
+    if (!mqtt_client.connected()) {
+        connectToMQTTBroker();
+    }
+    mqtt_client.loop();
+    
+    // 发布消息示例
+  static unsigned long lastMsg = 0;
+  if (millis() - lastMsg > 5000) {
+    lastMsg = millis();
+    
+    String message = "Hello from esp8266 - esp_connect_mqtt.ino_" + String(millis());
+    mqtt_client.publish(mqtt_topic_publish, message.c_str());
+    
+    Serial.println("消息已发布: " + message);
+  }
+}

mqtt-client-ESP8266/esp_mqtt_led.ino

@@ -0,0 +1,86 @@
+#include <ESP8266WiFi.h>
+#include <PubSubClient.h>
+
+// GPIO 5 D1
+#define LED 5
+
+// WiFi
+const char *ssid = "mousse"; // Enter your WiFi name
+const char *password = "qweqweqwe";  // Enter WiFi password
+
+// MQTT Broker
+const char *mqtt_broker = "broker.emqx.io";
+const char *topic = "esp8266/led";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 1883;
+
+bool ledState = false;
+
+WiFiClient espClient;
+PubSubClient client(espClient);
+
+
+void setup() {
+    // Set software serial baud to 115200;
+    Serial.begin(115200);
+    delay(1000); // Delay for stability
+
+    // Connecting to a WiFi network
+    WiFi.begin(ssid, password);
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.println("Connecting to WiFi...");
+    }
+    Serial.println("Connected to the WiFi network");
+
+    // Setting LED pin as output
+    pinMode(LED, OUTPUT);
+    digitalWrite(LED, LOW);  // Turn off the LED initially
+
+    // Connecting to an MQTT broker
+    client.setServer(mqtt_broker, mqtt_port);
+    client.setCallback(callback);
+    while (!client.connected()) {
+        String client_id = "esp8266-client-";
+        client_id += String(WiFi.macAddress());
+        Serial.printf("The client %s connects to the public MQTT broker\n", client_id.c_str());
+        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Public EMQX MQTT broker connected");
+        } else {
+            Serial.print("Failed with state ");
+            Serial.print(client.state());
+            delay(2000);
+        }
+    }
+
+    // Publish and subscribe
+    client.publish(topic, "hello emqx");
+    client.subscribe(topic);
+}
+
+void callback(char *topic, byte *payload, unsigned int length) {
+    Serial.print("Message arrived in topic: ");
+    Serial.println(topic);
+    Serial.print("Message: ");
+    String message;
+    for (int i = 0; i < length; i++) {
+        message += (char) payload[i];  // Convert *byte to string
+    }
+    Serial.print(message);
+    if (message == "on" && !ledState) {
+        digitalWrite(LED, HIGH);  // Turn on the LED
+        ledState = true;
+    }
+    if (message == "off" && ledState) {
+        digitalWrite(LED, LOW); // Turn off the LED
+        ledState = false;
+    }
+    Serial.println();
+    Serial.println("-----------------------");
+}
+
+void loop() {
+    client.loop();
+    delay(100); // Delay for a short period in each loop iteration
+}

mqtt-client-ESP8266/esp_mqtt_moisture.ino

@@ -0,0 +1,67 @@
+#include <ESP8266WiFi.h>
+#include <PubSubClient.h>
+#include <ArduinoJson.h>
+
+// WiFi
+const char *ssid = "mousse"; // Enter your WiFi name
+const char *password = "qweqweqwe";  // Enter WiFi password
+
+// MQTT Broker
+const char *mqtt_broker = "broker.emqx.io";
+const char *topic = "esp8266/test";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 1883;
+
+// Moisture
+#define sensorPIN A0
+unsigned long previousMillis = 0;
+
+WiFiClient espClient;
+PubSubClient client(espClient);
+
+void setup() {
+    // Set software serial baud to 115200;
+    Serial.begin(115200);
+    // connecting to a WiFi network
+    WiFi.begin(ssid, password);
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.println("Connecting to WiFi..");
+    }
+    Serial.println("Connected to the WiFi network");
+    //connecting to a mqtt broker
+    client.setServer(mqtt_broker, mqtt_port);
+    while (!client.connected()) {
+        String client_id = "esp8266-client-";
+        client_id += String(WiFi.macAddress());
+        Serial.printf("The client %s connects to the public mqtt broker\n", client_id.c_str());
+        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
+            Serial.println("Public emqx mqtt broker connected");
+        } else {
+            Serial.print("failed with state ");
+            Serial.print(client.state());
+            delay(2000);
+        }
+    }
+}
+
+
+void loop() {
+    client.loop();
+    unsigned long currentMillis = millis();
+    // temperature and humidity data are publish every five second
+    if (currentMillis - previousMillis >= 5000) {
+        previousMillis = currentMillis;
+        float moistureValue = analogRead(sensorPIN);
+        // json serialize
+        DynamicJsonDocument data(256);
+        data["moisture"] = moistureValue;
+        // publish moisture
+        char json_string[256];
+        serializeJson(data, json_string);
+        //
+        Serial.println(json_string);
+        client.publish(topic, json_string, false);
+    }
+}

mqtt-client-ESP8266/temp_hum.ino

@@ -0,0 +1,76 @@
+#include <ESP8266WiFi.h>
+#include <PubSubClient.h>
+#include <ArduinoJson.h>
+#include "DHT.h"
+
+// WiFi
+const char *ssid = "mousse"; // Enter your WiFi name
+const char *password = "qweqweqwe";  // Enter WiFi password
+
+// MQTT Broker
+const char *mqtt_broker = "broker.emqx.io";
+const char *topic = "temp_hum/kunming";
+const char *mqtt_username = "emqx";
+const char *mqtt_password = "public";
+const int mqtt_port = 1883;
+
+// DHT11
+#define DHTPIN D4
+#define DHTTYPE DHT11   // DHT 11
+unsigned long previousMillis = 0;
+
+WiFiClient espClient;
+PubSubClient client(espClient);
+DHT dht(DHTPIN, DHTTYPE);
+
+void setup() {
+    // Set software serial baud to 115200;
+    Serial.begin(115200);
+    // connecting to a WiFi network
+    WiFi.begin(ssid, password);
+    while (WiFi.status() != WL_CONNECTED) {
+        delay(500);
+        Serial.println("Connecting to WiFi..");
+    }
+    Serial.println("Connected to the WiFi network");
+    //connecting to a mqtt broker
+    client.setServer(mqtt_broker, mqtt_port);
+    client.setCallback(callback);
+    //connecting to a mqtt broker
+    while (!client.connected()) {
+        String client_id = "esp8266-client-";
+        client_id += String(WiFi.macAddress());
+        Serial.printf("The client %s connects to the public mqtt broker\n", client_id.c_str());
+        if (client.connect(client_id, mqtt_username, mqtt_password)) {
+            Serial.println("Public emqx mqtt broker connected");
+        } else {
+            Serial.print("failed with state ");
+            Serial.print(client.state());
+            delay(2000);
+        }
+    }
+    // dht11 begin
+    dht.begin();
+}
+
+
+void loop() {
+    client.loop();
+    unsigned long currentMillis = millis();
+    // temperature and humidity data are publish every five second
+    if (currentMillis - previousMillis >= 5000) {
+        previousMillis = currentMillis;
+        float temp = dht.readTemperature();
+        float hum = dht.readHumidity();
+        // json serialize
+        DynamicJsonDocument data(256);
+        data["temp"] = temp;
+        data["hum"] = hum;
+        // publish temperature and humidity
+        char json_string[256];
+        serializeJson(data, json_string);
+        // {"temp":23.5,"hum":55}
+        Serial.println(json_string);
+        client.publish(topic, json_string, false);
+    }
+}