wifi_SDread.ino

#include <WiFi.h>
#include "FS.h"
#include "SD.h"
#include "SPI.h"

const char* ssid     = "";
const char* password = "";

WiFiServer server(80);

String listDir(fs::FS &fs, const char * dirname, uint8_t levels){
    String s = "";
    
    File root = fs.open(dirname);
    if(!root){
        return s;
    }
    if(!root.isDirectory()){
        return s;
    }

    File file = root.openNextFile();
    while(file){
        if(file.isDirectory()){
            s.concat("  DIR : ");
            s.concat(file.name());
            s.concat("<br>");
            
            if(levels){
                listDir(fs, file.name(), levels -1);
            }
        } else {
            s.concat("  FILE: ");
            s.concat(file.name());
            s.concat("  SIZE: ");
            s.concat(file.size());
            s.concat("0000<br>");            
        }
        file = root.openNextFile();
    }
    return s;
}

void createDir(fs::FS &fs, const char * path){
    Serial.printf("Creating Dir: %s\n", path);
    if(fs.mkdir(path)){
        Serial.println("Dir created");
    } else {
        Serial.println("mkdir failed");
    }
}

String sd()
{
    if(!SD.begin()){
        Serial.println("Card Mount Failed");
        return "";
    }
    uint8_t cardType = SD.cardType();

    if(cardType == CARD_NONE){
        Serial.println("No SD card attached");
        return "";
    }

    uint64_t cardSize = SD.cardSize() / (1024 * 1024);
    Serial.printf("SD Card Size: %lluMB\n", cardSize);

    return listDir(SD, "/", 0);
}

void setup()
{
    Serial.begin(115200);

    Serial.println();
    Serial.println();
    Serial.print("Connecting to ");
    Serial.println(ssid);

    WiFi.begin(ssid, password);

    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }

    Serial.println("");
    Serial.println("WiFi connected.");
    Serial.println("IP address: ");
    Serial.println(WiFi.localIP());
    
    server.begin();
}

String sdlistdata;

void loop(){
 WiFiClient client = server.available();

  if (client) {
    Serial.println("New Client.");
    String currentLine = "";
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        Serial.write(c);
        if (c == '\n') {

          if (currentLine.length() == 0) {
            client.println("HTTP/1.1 200 OK");
            client.println("Content-type:text/html");
            client.println();
            client.print("Click <a href=\"/H\">reload</a><br>");
            client.println();
            client.print(sdlistdata);
            client.println();
            break;
          } else {
            currentLine = "";
          }
        } else if (c != '\r') {
          currentLine += c;
        }

        if (currentLine.endsWith("GET /H")) {
            sdlistdata = sd();
        }
      }
    }

    client.stop();
    Serial.println("Client Disconnected.");
  }
}