Redis is used in NodeJS programs

As a result of National Day period wife adult suddenly sees in the car front license plate soul to ask to say xiang F is where 😱 I which know where, I can only answer a sentence: I also don’t know 😂. In order to avoid the occurrence of similar soul to ask, I wrote a micro channel small program to facilitate query, wit 😜 data are on the Internet to climb, if interested in understanding how to climb can view the previous article [NodeJS climb news]; After the data is removed, it is found that you can add the function of querying basic information of the location, well, thanks to Baidu Baike. Considering that the data is crawled in real time, I thought that the location information may be constant for thousands of years, so I introduced Redis cache to process.

The local installation

Windows 10 is used locally.

• Download the corresponding program, decompress to the local
• Go to the directory and run the command./redis-server.exe redis.windows.conf

The specific Redis installation can be viewedNovice tutorial

Program dependency package

Download the Redis installation package

yarn add redis
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const redis = require('redis');
const redisClient = redis.createClient({
	host: '127.0.0.1'./ / the default host
  port: '6379' // Default port
});
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Data manipulation

You can use promisify to wrap operations into asynchronous functions

const redis = require('redis');
const { promisify } = require("util");
const config = require('.. /config');

const redisClient = redis.createClient(config.REDIS_PORT);

redisClient.on("error".function (err) {
  console.log("Error " + err);
});

function Client() {
  this.set = promisify(redisClient.set).bind(redisClient);
  this.get = promisify(redisClient.get).bind(redisClient);
  return this;
}

const client = new Client();

module.exports = client
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Refer to operations when you need to manipulate data

const redisStore = require('.. /utils/redis');

const getBaike = async (site) => {
  console.log(`site: ${site}`);
  if(! site) {return null; }...const data = {
    introduce,
    basicInfo
  };
  await redisStore.set(site, JSON.stringify(data));
  return data;
};

module.exports = async (ctx, next) => {
  await next();
  const { site } = ctx.query;
  const cacheData = await redisStore.get(site);
  const baike = cacheData ? JSON.parse(cacheData) : await getBaike(site);
  ctx.type = 'json';
  ctx.body = {
    baike
  }
}
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A simple Redis service operation is done.

cd /opt/redis
./bin/redis-server ./redis.conf
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/opt/redis/bin/redis-cli
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The last

Use their knowledge to solve some problems in life, feel good, we can experience or have good ideas, we communicate together.

Reference:

• Redis installation and deployment under Linux
• Redis tutorial