HTTP requests from Arduino - Mini Project: Build & Apply

HTTP requests from Arduino

📖 Scenario: You want to make your Arduino send data to a web server. This is useful for projects like weather stations or smart home devices that share information online.

🎯 Goal: Build a simple Arduino program that connects to WiFi and sends an HTTP GET request to a web server.

📋 What You'll Learn

Create a const char* variable called ssid with the WiFi network name

Create a const char* variable called password with the WiFi password

Create a const char* variable called server with the server address

Use WiFi.begin(ssid, password) to connect to WiFi

Use WiFiClient client to create a client

Use client.connect(server, 80) to connect to the server

Send an HTTP GET request using client.print()

Print the server response using Serial.println()

💡 Why This Matters

🌍 Real World

Many IoT devices send data to web servers to share sensor readings or receive commands.

💼 Career

Understanding how to make HTTP requests from embedded devices is useful for IoT developers and embedded systems engineers.

1

Set up WiFi credentials

Create two const char* variables called ssid and password. Set ssid to "YourNetwork" and password to "YourPassword".

Arduino

# Create 'ssid' and 'password' variables with the exact values
// Your code here

Need a hint?

Use const char* ssid = "YourNetwork"; and const char* password = "YourPassword";

2

Set up server address

Create a const char* variable called server and set it to "example.com".

Arduino

const char* ssid = "YourNetwork";
const char* password = "YourPassword";
// Create 'server' variable with value "example.com"
// Your code here

Need a hint?

Use const char* server = "example.com";

3

Connect to WiFi and server

In setup(), start serial communication with Serial.begin(115200). Use WiFi.begin(ssid, password) to connect to WiFi. Then create a WiFiClient called client and connect to the server on port 80 using client.connect(server, 80).

Arduino

const char* ssid = "YourNetwork";
const char* password = "YourPassword";
const char* server = "example.com";

void setup() {
  Serial.begin(115200);
  // Connect to WiFi
  WiFi.begin(ssid, password);
  // Create WiFiClient and connect to server
  // Your code here
}

void loop() {
}

Need a hint?

Use Serial.begin(115200);, WiFi.begin(ssid, password);, create WiFiClient client;, then client.connect(server, 80);

4

Send HTTP GET request and print response

After connecting to the server, send an HTTP GET request for the root path using client.print(). Then read the server response line by line using client.available() and client.readStringUntil('\n'). Print each line to serial using Serial.println().

Arduino

#include 

const char* ssid = "YourNetwork";
const char* password = "YourPassword";
const char* server = "example.com";

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected");

  WiFiClient client;
  if (client.connect(server, 80)) {
    Serial.println("Connected to server");
    // Send HTTP GET request and print response
    // Your code here
  } else {
    Serial.println("Connection failed");
  }
}

void loop() {
}

Need a hint?

Send the GET request with client.print(). Use a while loop with client.available() to read lines and print them with Serial.println().