Java
javaTutorial
What is the reason why the browser does not respond after the WebSocket server returns 401? How to solve it?
What is the reason why the browser does not respond after the WebSocket server returns 401? How to solve it?
Apr 19, 2025 pm 02:21 PM
Netty WebSocket server returns 401, browser unresponsive solution
When using Netty to build a WebSocket server and perform token verification, if the token is invalid, the server returns a 401 status code and closes the connection, but the browser may not react in any way. This article analyzes this problem and provides solutions.
Problem description
Tokens are required to develop WebSocket servers using Netty. When token verification fails, the server returns 401 and closes the connection, but the browser does not respond, and the front-end cannot know the reason for the connection to close. Server-side code example:
private void httpResponse401(ChannelHandlerContext ctx, FullHttpRequest request) {
FullHttpResponse response = new DefaultFullHttpResponse(request.protocolVersion(), HttpResponseStatus.UNAUTHORIZED);
response.headers().set(HttpHeaderNames.CONTENT_LENGTH, 0);
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
ReferenceCountUtil.release(request);
}
Front-end JavaScript code:
var socket = new WebSocket("ws://127.0.0.1:18080/ws?token=xxxx");
Although the server returns 401 and closes the connection, the browser does not respond in any way.
Solution
The browser is unresponsive because the 401 response is ignored during the WebSocket handshake phase. We need to process it during the handshake phase or after the connection is established.
Solution 1: Return 401 response during the handshake phase
In the WebSocket handshake phase (HTTP request phase), if token verification fails, the HTTP 401 response will be directly returned to avoid establishing a WebSocket connection. Modify the server-side code:
if (!validateToken(request)) {
FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.UNAUTHORIZED);
response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain; charset=utf-8");
response.headers().set(HttpHeaderNames.CONTENT_LENGTH, response.content().readableBytes());
ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
return;
}
Solution 2: Send custom messages after the connection is established
If you need to process 401 after the WebSocket connection is established, you can send a custom message to notify the front end immediately after the connection is established. Add a custom processor in Netty's WebSocketServerProtocolHandler :
channel.pipeline().addLast(new WebSocketServerProtocolHandler("/ws") {
@Override
public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
if (evt == WebSocketServerProtocolHandler.ServerHandshakeStateEvent.HANDSHAKE_COMPLETE) {
if (!validateToken()) {
ctx.writeAndFlush(new TextWebSocketFrame("401 Unauthorized")).addListener(ChannelFutureListener.CLOSE);
}
}
super.userEventTriggered(ctx, evt);
}
});
Front-end JavaScript code needs to listen for onmessage events:
socket.onmessage = function(event) {
if (event.data === "401 Unauthorized") {
console.log("Connection closed, reason: 401 Unauthorized");
socket.close();
}
};
Through the above method, the browser can correctly process the 401 status code, and the front-end can also receive corresponding feedback information, thereby solving the problem of the browser's unresponsiveness. Which solution to choose depends on the specific application scenario and requirements.
The above is the detailed content of What is the reason why the browser does not respond after the WebSocket server returns 401? How to solve it?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
The flow of funds on the chain is exposed: What new tokens are being bet on by Clever Money?
Jul 16, 2025 am 10:15 AM
Ordinary investors can discover potential tokens by tracking "smart money", which are high-profit addresses, and paying attention to their trends can provide leading indicators. 1. Use tools such as Nansen and Arkham Intelligence to analyze the data on the chain to view the buying and holdings of smart money; 2. Use Dune Analytics to obtain community-created dashboards to monitor the flow of funds; 3. Follow platforms such as Lookonchain to obtain real-time intelligence. Recently, Cangming Money is planning to re-polize LRT track, DePIN project, modular ecosystem and RWA protocol. For example, a certain LRT protocol has obtained a large amount of early deposits, a certain DePIN project has been accumulated continuously, a certain game public chain has been supported by the industry treasury, and a certain RWA protocol has attracted institutions to enter.
Who is suitable for stablecoin DAI_ Analysis of decentralized stablecoin usage scenarios
Jul 15, 2025 pm 11:27 PM
DAI is suitable for users who attach importance to the concept of decentralization, actively participate in the DeFi ecosystem, need cross-chain asset liquidity, and pursue asset transparency and autonomy. 1. Supporters of the decentralization concept trust smart contracts and community governance; 2. DeFi users can be used for lending, pledge, and liquidity mining; 3. Cross-chain users can achieve flexible transfer of multi-chain assets; 4. Governance participants can influence system decisions through voting. Its main scenarios include decentralized lending, asset hedging, liquidity mining, cross-border payments and community governance. At the same time, it is necessary to pay attention to system risks, mortgage fluctuations risks and technical threshold issues.
How to identify fake altcoins? Teach you to avoid cryptocurrency fraud
Jul 15, 2025 pm 10:36 PM
To identify fake altcoins, you need to start from six aspects. 1. Check and verify the background of the materials and project, including white papers, official websites, code open source addresses and team transparency; 2. Observe the online platform and give priority to mainstream exchanges; 3. Beware of high returns and people-pulling modes to avoid fund traps; 4. Analyze the contract code and token mechanism to check whether there are malicious functions; 5. Review community and media operations to identify false popularity; 6. Follow practical anti-fraud suggestions, such as not believing in recommendations or using professional wallets. The above steps can effectively avoid scams and protect asset security.
Bitcoin, Chainlink, and RWA resonance rise: crypto market enters institutional logic?
Jul 16, 2025 am 10:03 AM
The coordinated rise of Bitcoin, Chainlink and RWA marks the shift toward institutional narrative dominance in the crypto market. Bitcoin, as a macro hedging asset allocated by institutions, provides a stable foundation for the market; Chainlink has become a key bridge connecting the reality and the digital world through oracle and cross-chain technology; RWA provides a compliance path for traditional capital entry. The three jointly built a complete logical closed loop of institutional entry: 1) allocate BTC to stabilize the balance sheet; 2) expand on-chain asset management through RWA; 3) rely on Chainlink to build underlying infrastructure, indicating that the market has entered a new stage driven by real demand.
Which is better, DAI or USDC?_Is DAI suitable for long-term holding?
Jul 15, 2025 pm 11:18 PM
Is DAI suitable for long-term holding? The answer depends on individual needs and risk preferences. 1. DAI is a decentralized stablecoin, generated by excessive collateral for crypto assets, suitable for users who pursue censorship resistance and transparency; 2. Its stability is slightly inferior to USDC, and may experience slight deansal due to collateral fluctuations; 3. Applicable to lending, pledge and governance scenarios in the DeFi ecosystem; 4. Pay attention to the upgrade and governance risks of MakerDAO system. If you pursue high stability and compliance guarantees, it is recommended to choose USDC; if you attach importance to the concept of decentralization and actively participate in DeFi applications, DAI has long-term value. The combination of the two can also improve the security and flexibility of asset allocation.
The role of Ethereum smart contracts
Jul 15, 2025 pm 09:18 PM
The role of Ethereum smart contract is to realize decentralized, automated and transparent protocol execution. Its core functions include: 1. As the core logic layer of DApp, it supports token issuance, DeFi, NFT and other functions; 2. Automatically execute contracts through code to reduce the risks of human intervention and fraud; 3. Build a DeFi ecosystem so that users can directly conduct financial operations such as lending and transactions; 4. Create and manage digital assets to ensure uniqueness and verifiability; 5. Improve the transparency and security of supply chain and identity verification; 6. Support DAO governance and realize decentralized decision-making.
Pre-sales of Filecoin, Render, and AI storage are heating up: Is the explosion point of Web3 infrastructure coming?
Jul 16, 2025 am 09:51 AM
Yes, Web3 infrastructure is exploding expectations as demand for AI heats up. Filecoin integrates computing power through the "Compute over Data" plan to support AI data processing and training; Render Network provides distributed GPU computing power to serve AIGC graph rendering; Arweave supports AI model weights and data traceability with permanent storage characteristics; the three are combining technology upgrades and ecological capital promotion, and are moving from the edge to the underlying core of AI.
How much is a stablecoin USD
Jul 15, 2025 pm 09:57 PM
The value of stablecoins is usually pegged to the US dollar 1:1, but it will fluctuate slightly due to factors such as market supply and demand, investor confidence and reserve assets. For example, USDT fell to $0.87 in 2018, and USDC fell to around $0.87 in 2023 due to the Silicon Valley banking crisis. The anchoring mechanism of stablecoins mainly includes: 1. fiat currency reserve type (such as USDT, USDC), which relies on the issuer's reserves; 2. cryptocurrency mortgage type (such as DAI), which maintains stability by over-collateralizing other cryptocurrencies; 3. Algorithmic stablecoins (such as UST), which relies on algorithms to adjust supply, but have higher risks. Common trading platforms recommendations include: 1. Binance, providing rich trading products and strong liquidity; 2. OKX,
