feat(external): #469 Add HttpFallbackHandler to determine if it's a WebSocket upgrade request.

Author: iohao

external/external-netty/src/main/java/com/iohao/game/external/core/netty/handler/check/HttpFallbackHandler.java

@@ -0,0 +1,55 @@
+/*
+ * ioGame
+ * Copyright (C) 2021 - present  渔民小镇 （262610965@qq.com、luoyizhu@gmail.com） . All Rights Reserved.
+ * # iohao.com . 渔民小镇
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.iohao.game.external.core.netty.handler.check;
+
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.SimpleChannelInboundHandler;
+import io.netty.handler.codec.http.*;
+
+/**
+ * @author 渔民小镇
+ * @date 2025-06-28
+ * @since 21.29
+ */
+@ChannelHandler.Sharable
+public final class HttpFallbackHandler extends SimpleChannelInboundHandler<FullHttpRequest> {
+
+    @Override
+    protected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest req) {
+        // 检查是否是 WebSocket 升级请求
+        if ("websocket".equalsIgnoreCase(req.headers().get(HttpHeaderNames.UPGRADE))) {
+            ctx.fireChannelRead(req.retain());
+        } else {
+            ctx.close();
+        }
+    }
+
+    private HttpFallbackHandler() {
+    }
+
+    public static HttpFallbackHandler me() {
+        return Holder.ME;
+    }
+
+    /** 通过 JVM 的类加载机制, 保证只加载一次 (singleton) */
+    private static class Holder {
+        static final HttpFallbackHandler ME = new HttpFallbackHandler();
+    }
+}

external/external-netty/src/main/java/com/iohao/game/external/core/netty/handler/check/TcpProtocolSanityCheckHandler.java

@@ -0,0 +1,55 @@
+/*
+ * ioGame
+ * Copyright (C) 2021 - present  渔民小镇 （262610965@qq.com、luoyizhu@gmail.com） . All Rights Reserved.
+ * # iohao.com . 渔民小镇
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.iohao.game.external.core.netty.handler.check;
+
+import com.iohao.game.external.core.config.ExternalGlobalConfig;
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+
+import java.util.List;
+
+/**
+ * @author 渔民小镇
+ * @date 2025-06-28
+ * @since 21.29
+ */
+public final class TcpProtocolSanityCheckHandler extends ByteToMessageDecoder {
+    private boolean closed = false;
+
+    @Override
+    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) {
+
+        if (closed || in.readableBytes() < 4) {
+            return;
+        }
+
+        in.markReaderIndex();
+        int length = in.readInt();
+        in.resetReaderIndex();
+
+        if (length <= 0 || length > ExternalGlobalConfig.CoreOption.packageMaxSize) {
+            closed = true;
+            ctx.close();
+        } else {
+            ctx.pipeline().remove(this);
+        }
+    }
+}

external/external-netty/src/main/java/com/iohao/game/external/core/netty/micro/TcpMicroBootstrapFlow.java

@@ -60,6 +60,8 @@ public void option(ServerBootstrap bootstrap) {
 
     @Override
     public void pipelineCodec(PipelineContext context) {
+//        context.addLast("tcp-check", new TcpProtocolSanityCheckHandler());
+
         // 数据包长度 = 长度域的值 + lengthFieldOffset + lengthFieldLength + lengthAdjustment。
         context.addLast(new LengthFieldBasedFrameDecoder(
                 ExternalGlobalConfig.CoreOption.packageMaxSize,

external/external-netty/src/main/java/com/iohao/game/external/core/netty/micro/WebSocketMicroBootstrapFlow.java

@@ -22,6 +22,7 @@
 import com.iohao.game.external.core.config.ExternalGlobalConfig;
 import com.iohao.game.external.core.micro.PipelineContext;
 import com.iohao.game.external.core.netty.handler.codec.WebSocketExternalCodec;
+import com.iohao.game.external.core.netty.handler.check.HttpFallbackHandler;
 import com.iohao.game.external.core.netty.handler.ws.WebSocketVerifyHandler;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.ChannelOption;
@@ -140,5 +141,7 @@ protected void httpHandler(PipelineContext context) {
          * 到完整的 Http 请求或响应
          */
         context.addLast("aggregator", new HttpObjectAggregator(65536));
+
+        context.addLast("http-fallback", HttpFallbackHandler.me());
     }
 }