Using Redis and JavaScript to build a real-time stock quotation system: how to quickly update data

Using Redis and JavaScript to build a real-time stock quotation system: how to quickly update data

With the continuous development of the capital market, investors' demand for real-time stock quotations is also increasing. Building a real-time stock quotation system that quickly updates data is undoubtedly the pursuit of investors. This article will introduce how to use Redis and JavaScript to build such a system, and provide corresponding code examples.

1. Introduction to Redis

Redis is a high-performance key-value pair storage database that uses memory as the storage medium and can be read and written quickly. It supports a variety of data structures, including strings, hash tables, lists, sets, ordered sets, etc. In the real-time stock quotation system, we can use Redis to save stock data to meet the need for rapid data update.

2. System Design

When building a real-time stock quotation system, we need to consider the following design aspects:

1. Data source: We need to start from the data Source to obtain stock market data. For example, a third-party API can be used to obtain stock prices in real time.
2. Data storage: We use Redis to store stock market data. For each stock, we can use a hash table to save the corresponding data, such as stock code, current price, increase and decrease, etc.
3. Data update: We need to update stock market data regularly. You can use JavaScript timers to regularly obtain stock market data from the data source and store the updated data in Redis.
4. Data subscription: In order to update stock quotes in real time, in the front-end page, we can use WebSocket to establish a long connection with the server and subscribe to the specified stock code. When the stock market data is updated, the server will push the data to the front-end page in real time.

3. Code Example

The following is a code example that uses Node.js and Redis modules to build a real-time stock quotation system:

// 引入所需模块
var redis = require("redis");
var WebSocket = require("websocket").server;

// 创建Redis客户端
var redisClient = redis.createClient();

// 创建WebSocket服务器
var webSocketServer = new WebSocket({
  httpServer: httpServer
});

// 监听WebSocket连接事件
webSocketServer.on("request", function(request) {
  // 接受连接请求
  var connection = request.accept(null, request.origin);

  // 监听客户端发送的订阅股票请求
  connection.on("message", function(message) {
    var stockCode = message.utf8Data;

    // 订阅指定股票数据
    redisClient.subscribe(stockCode);
  });

  // 监听Redis发布的股票数据更新
  redisClient.on("message", function(channel, message) {
    // 发送实时股票行情数据给客户端
    connection.sendUTF(message);
  });

  // 监听连接关闭事件
  connection.on("close", function(reasonCode, description) {
    // 取消订阅已关闭连接的股票
    redisClient.unsubscribe();
  });
});

// 定时获取股票行情数据并更新到Redis中
setInterval(function() {
  // 使用第三方API获取股票行情数据
  var stockData = getStockData();

  // 将数据存储到Redis中
  redisClient.hmset(stockData.stockCode, stockData);
}, 5000);

In the above code, we The Redis module is used to create the Redis client, and the WebSocket module is used to create the WebSocket server. When the WebSocket connection is established, we listen to the request to subscribe to the stock, and after receiving the subscription request, use the stock code as the channel name to subscribe to the corresponding stock data in Redis. When Redis receives stock data updates, we push the data to the client in real time via WebSocket. The timer fetches stock quotation data from the third-party API every 5 seconds and stores the data into Redis.

Through the above code examples, we can build a real-time stock quotation system and achieve the need to quickly update data. Investors can obtain information such as stock prices and price increases and decreases in real time, allowing them to make more accurate investment decisions.

Conclusion

Use Redis and JavaScript to build a real-time stock quotation system, which can quickly update data and push stock quotation data to investors in real time. At the same time, this also provides investors with a more accurate basis for decision-making. I hope this article will be helpful to you in building a real-time stock quotation system.

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