ESP32 WebServer Library – streamFile()

/*
 * Author: Avant Maker
 * Date: March 17, 2025
 * Version: 1.0
 * License: MIT 
 * 
 * Description: 
 * This example demonstrates how to use ESP32 WebServer Library's 
 * streamFile() to serve an HTML file stored in SPIFFS to a client
 * when they access the root URL ("/"). It allows the ESP32 to
 * efficiently send large files without loading the entire file
 * into memory.
 *
 * 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/home/all-about-esp32-arduino-core-library/
 *
 * 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 <WebServer.h>
#include <FS.h>
#include <LittleFS.h>

// Network credentials
const char* ssid = "your-SSID";          // Replace with your Wi-Fi SSID
const char* password = "your-PASSWORD";  // Replace with your Wi-Fi password

// Web server port number
WebServer server(80);

// File paths
const char* indexPath = "/index.html";

// MIME types for common file extensions
const char* getContentType(String filename) {
  if (filename.endsWith(".html")) return "text/html";
  else if (filename.endsWith(".css")) return "text/css";
  else if (filename.endsWith(".js")) return "application/javascript";
  else if (filename.endsWith(".ico")) return "image/x-icon";
  else if (filename.endsWith(".json")) return "application/json";
  else if (filename.endsWith(".png")) return "image/png";
  else if (filename.endsWith(".jpg")) return "image/jpeg";
  else if (filename.endsWith(".gif")) return "image/gif";
  else if (filename.endsWith(".svg")) return "image/svg+xml";
  return "text/plain";
}

void setup() {
  // Initialize serial communication
  Serial.begin(115200);
  
  // Initialize LittleFS
  if (!LittleFS.begin()) {
    Serial.println("LittleFS mount failed");
    return;
  }
  Serial.println("LittleFS mounted successfully");
  
  // List files in LittleFS for debugging
  listFiles();
  
  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  Serial.println("Connecting to WiFi");
  
  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
  
  // Define server routes
  server.on("/", HTTP_GET, handleRoot);
  
  // Define handler for any file request
  server.onNotFound(handleNotFound);
  
  // Start server
  server.begin();
  Serial.println("HTTP server started");
}

void loop() {
  // Handle client requests
  server.handleClient();
  delay(10);
}

// Handler for root page
void handleRoot() {
  serveFile(indexPath);
}

// Handle file requests using streamFile method
void serveFile(const char* path) {
  Serial.print("Requested file: ");
  Serial.println(path);
  
  if (LittleFS.exists(path)) {
    File file = LittleFS.open(path, "r");
    if (file) {
      // Get MIME type based on file extension
      String contentType = getContentType(String(path));
      
      // Stream the file to the client
      server.streamFile(file, contentType);
      
      // Close the file when done
      file.close();
      Serial.println("File served successfully");
    } else {
      Serial.println("Failed to open file for reading");
      server.send(500, "text/plain", "Internal Server Error");
    }
  } else {
    Serial.println("File not found");
    server.send(404, "text/plain", "File Not Found");
  }
}

// Handle requests for files not found
void handleNotFound() {
  // Check if the requested URI is a file
  String path = server.uri();
  
  // If the path doesn't start with a slash, add one
  if (!path.startsWith("/")) {
    path = "/" + path;
  }
  
  // Try to serve the file
  if (LittleFS.exists(path)) {
    serveFile(path.c_str());
  } else {
    // If file doesn't exist, return 404
    String message = "File Not Found\n\n";
    message += "URI: ";
    message += server.uri();
    message += "\nMethod: ";
    message += (server.method() == HTTP_GET) ? "GET" : "POST";
    message += "\nArguments: ";
    message += server.args();
    message += "\n";
    
    for (uint8_t i = 0; i < server.args(); i++) {
      message += " " + server.argName(i) + ": " + server.arg(i) + "\n";
    }
    
    server.send(404, "text/plain", message);
  }
}

// List all files in LittleFS (for debugging)
void listFiles() {
  Serial.println("Files in LittleFS:");
  
  File root = LittleFS.open("/", "r");
  if (!root) {
    Serial.println("Failed to open directory");
    return;
  }
  if (!root.isDirectory()) {
    Serial.println("Not a directory");
    return;
  }
  
  File file = root.openNextFile();
  while (file) {
    if (file.isDirectory()) {
      Serial.print("DIR: ");
    } else {
      Serial.print("FILE: ");
      Serial.print(file.name());
      Serial.print(" (");
      Serial.print(file.size());
      Serial.println(" bytes)");
    }
    file = root.openNextFile();
  }
  Serial.println("---------------------");
}

/*
 * Author: Avant Maker
 * Date: March 17, 2025
 * Version: 1.0
 * License: MIT 
 * 
 * Description: 
 * This example demonstrates how to use ESP32 WebServer Library's 
 * streamFile() to stream a JPEG image from SPIFFS with a custom
 * HTTP status code. It checks if the file exists and sends a
 * 404 status if it doesn't.
 *
 * 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/home/all-about-esp32-arduino-core-library/
 *
 * 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 <WebServer.h>
#include <FS.h>
#include <SPIFFS.h>

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

WebServer server(80);

void setup() {
    Serial.begin(115200);
    SPIFFS.begin();
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("Connected: ");
    Serial.println(WiFi.localIP());

    server.on("/image", []() {
        File file = SPIFFS.open("/photo.jpg", "r");
        if (file) {
            size_t sent = server.streamFile(file, "image/jpeg", 200);
            Serial.print("Bytes sent: ");
            Serial.println(sent);
            file.close();
        } else {
            server.streamFile(file, "text/plain", 404); // File object is invalid, but status is set
            server.send(404, "text/plain", "Image not found");
        }
    });
    server.begin();
}

void loop() {
    server.handleClient();
}