Update license headers on source files to be compliant with LGPL, by …

…using the SPDX identifier.

The project is under LGPL license so the source files should reflect that by having a license header compliant with LGPL, or at least have an appropriate SPDX header.
This changed is required to allow the source files to be used in downstream project because some files are not licensed in accordance to the LPGL rules.
Refs:
- https://www.gnu.org/licenses/gpl-howto.html
- https://spdx.dev/learn/handling-license-info/
- https://spdx.org/licenses/LGPL-3.0-or-later.html

examples/CaptivePortal/CaptivePortal.ino

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include <DNSServer.h>
 #ifdef ESP32
 #include <AsyncTCP.h>

examples/Filters/Filters.ino

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 // Reproduced issue https://github.com/ESP32Async/ESPAsyncWebServer/issues/26
 
 #include <DNSServer.h>

examples/Issue162/Issue162.ino

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 /**
  *
  * Connect to AP and run in bash:

examples/Issue85/Issue85.ino

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 /**
  *
  * Connect to AP and run in bash:

examples/SSE_perftest/SSE_perftest.ino

@@ -1,4 +1,6 @@
-//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 //  SSE server with a load generator
 //  it will auto adjust message push rate to minimize discards across all connected clients
 //  per second stats is printed to a serial console and also published as SSE ping message

examples/SimpleServer/SimpleServer.ino

@@ -1,9 +1,10 @@
-//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 // A simple server implementation showing how to:
 //  * serve static messages
 //  * read GET and POST parameters
 //  * handle missing pages / 404s
-//
 
 #include <Arduino.h>
 #ifdef ESP32

examples/StreamFiles/StreamConcat.h

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #pragma once
 
 #include <Stream.h>

examples/StreamFiles/StreamFiles.ino

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include <Arduino.h>
 #include <DNSServer.h>
 #ifdef ESP32

src/AsyncEventSource.cpp

@@ -1,22 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
 #include "Arduino.h"
 #if defined(ESP32)
 #include <rom/ets_sys.h>

src/AsyncEventSource.h

@@ -1,22 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
 #ifndef ASYNCEVENTSOURCE_H_
 #define ASYNCEVENTSOURCE_H_
 

src/AsyncJson.cpp

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include "AsyncJson.h"
 
 #if ASYNC_JSON_SUPPORT == 1

src/AsyncJson.h

@@ -1,37 +1,6 @@
-// AsyncJson.h
-/*
-  Async Response to use with ArduinoJson and AsyncWebServer
-  Written by Andrew Melvin (SticilFace) with help from me-no-dev and BBlanchon.
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  Example of callback in use
-
-   server.on("/json", HTTP_ANY, [](AsyncWebServerRequest * request) {
-
-    AsyncJsonResponse * response = new AsyncJsonResponse();
-    JsonObject& root = response->getRoot();
-    root["key1"] = "key number one";
-    JsonObject& nested = root.createNestedObject("nested");
-    nested["key1"] = "key number one";
-
-    response->setLength();
-    request->send(response);
-  });
-
-  --------------------
-
-  Async Request to use with ArduinoJson and AsyncWebServer
-  Written by Arsène von Wyss (avonwyss)
-
-  Example
-
-  AsyncCallbackJsonWebHandler* handler = new AsyncCallbackJsonWebHandler("/rest/endpoint");
-  handler->onRequest([](AsyncWebServerRequest *request, JsonVariant &json) {
-    JsonObject jsonObj = json.as<JsonObject>();
-    // ...
-  });
-  server.addHandler(handler);
-
-*/
 #ifndef ASYNC_JSON_H_
 #define ASYNC_JSON_H_
 

src/AsyncMessagePack.cpp

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include "AsyncMessagePack.h"
 
 #if ASYNC_MSG_PACK_SUPPORT == 1

src/AsyncMessagePack.h

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #pragma once
 
 /*

src/AsyncWebHeader.cpp

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include <ESPAsyncWebServer.h>
 
 AsyncWebHeader::AsyncWebHeader(const String &data) {

src/AsyncWebSocket.cpp

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
 #include "AsyncWebSocket.h"
 #include "Arduino.h"
 

src/AsyncWebSocket.h

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #ifndef ASYNCWEBSOCKET_H_
 #define ASYNCWEBSOCKET_H_
 

src/ChunkPrint.cpp

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include <ChunkPrint.h>
 
 ChunkPrint::ChunkPrint(uint8_t *destination, size_t from, size_t len) : _destination(destination), _to_skip(from), _to_write(len), _pos{0} {}

src/ChunkPrint.h

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #ifndef CHUNKPRINT_H
 #define CHUNKPRINT_H
 

src/ESPAsyncWebServer.h

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
 #ifndef _ESPAsyncWebServer_H_
 #define _ESPAsyncWebServer_H_
 

src/Middleware.cpp

@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include "WebAuthentication.h"
 #include <ESPAsyncWebServer.h>
 

src/WebAuthentication.cpp

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include "WebAuthentication.h"
 #include <libb64/cencode.h>
 #if defined(ESP32) || defined(TARGET_RP2040)

src/WebAuthentication.h

@@ -1,23 +1,5 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
 #ifndef WEB_AUTHENTICATION_H_
 #define WEB_AUTHENTICATION_H_

src/WebHandlerImpl.h

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
 
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
 #ifndef ASYNCWEBSERVERHANDLERIMPL_H_
 #define ASYNCWEBSERVERHANDLERIMPL_H_
 

src/WebHandlers.cpp

@@ -1,23 +1,6 @@
-/*
-  Asynchronous WebServer library for Espressif MCUs
-
-  Copyright (c) 2016 Hristo Gochkov. All rights reserved.
-  This file is part of the esp8266 core for Arduino environment.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+
 #include "ESPAsyncWebServer.h"
 #include "WebHandlerImpl.h"