ESP32 HTTPClient Library – errorToString

/*
 * Author: Avant Maker
 * Date: February 24, 2025
 * Version: 1.0
 * Description: This code connects an ESP32 to WiFi and attempts 
 * to perform a GET request to www.httpbin.org. If an error occurs,
 * it uses errorToString to print a readable error message
 * to the Serial Monitor.
 *
 * License: MIT 
 * 
 * Code Source: This example code is sourced from the Comprehensive 
 * Guide to the ESP32 Arduino Core Library, accessible on 
 * AvantMaker.com. For additional code examples and in-depth 
 * documentation related to the ESP32 Arduino Core Library, 
 * please visit:
 *
 * https://avantmaker.com/references/esp32-arduino-core-index/
 *
 * AvantMaker.com, your premier destination for all things 
 * DIY, AI, IoT, Smart Home, and STEM projects. We are dedicated 
 * to empowering makers, learners, and enthusiasts with the resources
 * they need to bring their innovative ideas to life.
 */

#include <WiFi.h>
#include <HTTPClient.h>

const char* ssid = "your-SSID";       // Replace with your WiFi SSID
const char* password = "your-PASSWORD"; // Replace with your WiFi password

void setup() {
    Serial.begin(115200);
    WiFi.begin(ssid, password);

    // Wait for WiFi connection
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("\nConnected to WiFi");
}

void loop() {
    HTTPClient http;

    // Begin HTTP request to a test endpoint
    http.begin("http://www.httpbin.org/get");

    // Send GET request
    int httpCode = http.GET();

    // Check if the request was successful
    if (httpCode > 0) {
        Serial.printf("Request succeeded with code: %d\n", httpCode);
    } else {
        // Print error message using errorToString
        String errorMessage = http.errorToString(httpCode);
        Serial.printf("Request failed with error: %s\n", errorMessage.c_str());
    }

    // Clean up
    http.end();

    delay(5000); // Wait 5 seconds before the next request
}

/*
 * Author: Avant Maker
 * Date: February 24, 2025
 * Version: 1.0
 * Description: demonstrates how to retrieve and display 
 * error messages associated with the HTTPClient library's
 * error codes. The program iterates through error codes
 * from -1 to -11, converting each to its corresponding
 * string representation using errorToString.
 * It then prints both the error code and a detailed
 * explanation to the Serial Monitor.
 *
 * License: MIT 
 * 
 * Code Source: This example code is sourced from the Comprehensive 
 * Guide to the ESP32 Arduino Core Library, accessible on 
 * AvantMaker.com. For additional code examples and in-depth 
 * documentation related to the ESP32 Arduino Core Library, 
 * please visit:
 *
 * https://avantmaker.com/references/esp32-arduino-core-index/
 *
 * AvantMaker.com, your premier destination for all things 
 * DIY, AI, IoT, Smart Home, and STEM projects. We are dedicated 
 * to empowering makers, learners, and enthusiasts with the resources
 * they need to bring their innovative ideas to life.
 */

#include <WiFi.h>
#include <HTTPClient.h>

void setup() {
    Serial.begin(115200);
    delay(1000); // Give Serial Monitor time to initialize
    Serial.println("ESP32 HTTPClient Error Codes:");

    HTTPClient http; // Create an instance to access errorToString

    // Loop through error codes -1 to -11
    for (int errorCode = -1; errorCode >= -11; errorCode--) {
        String errorMessage = http.errorToString(errorCode);
        Serial.printf("%d (%s): ", errorCode, errorMessage.c_str());

        // Map error codes to their detailed descriptions
        switch (errorCode) {
            case -1:
                Serial.println("Connection to the server was refused.");
                break;
            case -2:
                Serial.println("Failed to send HTTP headers.");
                break;
            case -3:
                Serial.println("Failed to send payload (not typically applicable to GET).");
                break;
            case -4:
                Serial.println("Not connected to the server.");
                break;
            case -5:
                Serial.println("Connection to the server was lost.");
                break;
            case -6:
                Serial.println("No stream available to read the response.");
                break;
            case -7:
                Serial.println("Server did not respond as an HTTP server.");
                break;
            case -8:
                Serial.println("Insufficient RAM to complete the operation.");
                break;
            case -9:
                Serial.println("Transfer encoding error (e.g., unsupported chunked encoding).");
                break;
            case -10:
                Serial.println("Error writing to the stream.");
                break;
            case -11:
                Serial.println("Read operation timed out.");
                break;
            default:
                Serial.println("Unknown error.");
                break;
        }
    }

    // Clean up (not strictly necessary here, but good practice)
    http.end();
}

void loop() {
    // Empty loop, as we only need to run this once in setup
}