Simple File Upload

src/WebContent.h

@@ -41,6 +41,8 @@ const char index_html[] PROGMEM = R"rawliteral(
    <h2>🎶 Playlist 🎶</h2>
    %DIRECTORY%
    </p>
+
+   <form method="POST" action="/upload" enctype="multipart/form-data"><input type="file" name="data"/><input type="submit" name="upload" value="Upload" title="Upload File"></form>
    
    <script>
     setInterval(getState, 4000);

src/main.cpp

@@ -120,6 +120,40 @@ void deactivateRFID()
   digitalWrite(CS_RFID, HIGH);
 }
 
+// Make size of files human readable
+// source: https://github.com/CelliesProjects/minimalUploadAuthESP32
+String humanReadableSize(const size_t bytes) {
+  if (bytes < 1024) return String(bytes) + " B";
+  else if (bytes < (1024 * 1024)) return String(bytes / 1024.0) + " KB";
+  else if (bytes < (1024 * 1024 * 1024)) return String(bytes / 1024.0 / 1024.0) + " MB";
+  else return String(bytes / 1024.0 / 1024.0 / 1024.0) + " GB";
+}
+
+void handleUpload(AsyncWebServerRequest *request, String filename, size_t index, uint8_t *data, size_t len, bool final) {
+  if (!index) {
+    logmessage = "Upload Start: " + String(filename);
+    // open the file on first call and store the file handle in the request object
+    request->_tempFile = SD.open("/"+filename, FILE_WRITE);
+    Serial.println(logmessage);
+  }
+
+  if (len) {
+    // stream the incoming chunk to the opened file
+    request->_tempFile.write(data, len);
+    
+    //logmessage = "Writing file: " + String(filename) + " index=" + String(index) + " len=" + String(len);
+    Serial.println(logmessage);
+  }
+
+  if (final) {
+    logmessage = "Upload Complete: " + String(filename) + ",size: " + String(index + len);
+    // close the file handle as the upload is now done
+    request->_tempFile.close();
+    Serial.println(logmessage);
+    request->redirect("/");
+  }
+}
+
 uint32_t getBatteryVoltageMv() {
   uint32_t voltage = analogReadMilliVolts(BAT_VOLTAGE_PIN);
   Serial.print("Battery Voltage: ");
@@ -589,6 +623,11 @@ void setup()
 
     server.on("/volume", HTTP_POST, volume_action);
 
+      // run handleUpload function when any file is uploaded
+    server.on("/upload", HTTP_POST, [](AsyncWebServerRequest *request) {
+        request->send(200);
+      }, handleUpload);
+
     server.begin();
     Serial.println("Wifi initialized.");
   } else {