/* 10.020 - Simple HTTP client
This sketch receives data via HTTP GET requests to fetch a text file from a web server.
To try it our, either use it as-is (in which case, your ESP32 will retrieve the text in my
sample text file), or upload a text file in your own web server and change the host and url strings.
This sketch was written by Peter Dalmaris using information from the
ESP32 datasheet and examples.
Components
----------
- ESP32 Dev Kit v4
IDE
---
Arduino IDE with ESP32 Arduino Code
(https://github.com/espressif/arduino-esp32)
Libraries
---------
- WiFi (comes with the ESP32 Arduino core)
Connections
-----------
No connections needed, the ESP32 is the only hardware.
Other information
-----------------
1. ESP32 Datasheet: https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
2. Wifi library: https://github.com/espressif/arduino-esp32/tree/master/libraries/WiFi
3. The remote text file is at: https://txplore-downloads.s3.amazonaws.com/esp32/test_file.txt
Created on April 8 2019 by Peter Dalmaris
*/
#include <WiFi.h>
const char* host = "txplore-downloads.s3.amazonaws.com"; // Change this for your own server
String url = "/esp32/test_file.txt"; // Change this for your own file
void setup()
{
Serial.begin(115200);
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to Wifi");
WiFi.begin("Wokwi-GUEST", "", 6);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void loop()
{
delay(5000);
Serial.print("connecting to ");
Serial.println(host);
// Use WiFiClient class to create TCP connections
WiFiClient client;
const int httpPort = 80;
if (!client.connect(host, httpPort)) {
Serial.println("connection failed");
return;
}
// We now create a URI for the request
Serial.print("Requesting URL: ");
Serial.println(url);
// This will send the request to the server
client.print(String("GET ") + url + " HTTP/1.1\r\n" +
"Host: " + host + "\r\n" +
"Connection: close\r\n\r\n");
unsigned long timeout = millis();
while (client.available() == 0) {
if (millis() - timeout > 5000) {
Serial.println(">>> Client Timeout !");
client.stop();
return;
}
}
// Read all the lines of the reply from server and print them to Serial
while(client.available()) {
String line = client.readStringUntil('\r');
Serial.print(line);
}
Serial.println();
Serial.println("closing connection");
}