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  • node js 操作redis promise

    连接

    redis = require('redis')
    var client = redis.createClient('6379', '127.0.0.1');
    
    client.on('connect', function() {
        console.log('connected');
    });
    

    基础操作

    /**
     * 1、字符串数据类型
     */
    	
    var res = client.set('name', 'abczhijia', (err, data) => {
        console.log('err: ', err, ' data: ', data);
    }); // err:  null  data:  OK,res的值是true
    	
    client.get('name',  (err, data) => {
        console.log('err: ', err, ' data: ', data);
    }); // err:  null  data:  abczhijia
    	
    const cb = (err, data) => {
        console.log('err: ', err, ' data: ', data, ' data type: ', typeof data);
    }
    	
    	
    client.set('age', 20, cb); //err:  null  data:  OK  data type:  string
    client.get('age', cb); //err:  null  data:  20  data type:  string
    	
    	
    /**
     * 2、列表数据类型
     */
    	
    //从右侧推入
    client.rpush('friends', 'mike', 'jhon', cb); //err:  null  data:  2  data type:  number
    client.lrange('friends', 0, -1, cb); //err:  null  data:  [ 'mike', 'jhon' ]  data type:  object
    	
    //从左侧推入
    client.lpush('friends', 'sam', 'bob', cb); //err:  null  data:  4  data type:  number
    client.lrange('friends', 0, -1, cb); // err:  null  data:  [ 'bob', 'sam', 'mike', 'jhon' ]  data type:  object
    	
    //从右侧弹出
    client.rpop('friends', cb); //err:  null  data:  jhon  data type:  string
    //从左侧弹出
    client.lpop('friends', cb); //err:  null  data:  bob  data type:  string
    //打印看看发生了啥
    client.lrange('friends', 0, -1, cb); // err:  null  data:  [ 'sam', 'mike' ]  data type:  object
    	
    //查看索引位置的值
    client.lindex('friends', 0, cb); //err:  null  data:  sam  data type:  string
    	
    //对列表进行裁剪
    client.rpush('friends', 'tom', 'bryant', cb)// err:  null  data:  4  data type:  number
    client.ltrim('friends', 1, 2, cb); //err:  null  data:  OK  data type:  string
    client.lrange('friends', 0, -1, cb); //err:  null  data:  [ 'mike', 'tom' ]  data type:  object
    	
    /**
     * 3、集合数据类型
     */
    	
    //往集合ids中加几个元素
    client.sadd('ids', 1, 2, cb);  //err:  null  data:  2  data type:  number
    //查看集合元素
    client.smembers('ids', cb); //err:  null  data:  [ '1', '2' ]  data type:  object
    //从集合中删除元素
    client.srem('ids', 2, cb); // err:  null  data:  1  data type:  number
    //看看发生了啥
    client.smembers('ids', cb); //err:  null  data:  [ '1' ]  data type:  object
    //看看集合有多少个元素
    client.scard('ids', cb); //err:  null  data:  1  data type:  number
    //再加几个元素进去
    client.sadd('ids', 3, 5, 8, 9); //
    //判断元素是否在集合内
    client.sismember('ids', 8, cb); // err:  null  data:  1  data type:  number
    client.sismember('ids', 80, cb); //err:  null  data:  0  data type:  number
    	
    	
    /**
     *4、散列数据类型 
     */
    	
    //往散列上添加多组键值对
    client.hmset('phone', 'price', 5888, 'name', 'iphonex', cb); //err:  null  data:  OK  data type:  string
    //查看多个键的值
    client.hmget('phone', 'price', 'name', cb); //err:  null  data:  [ '5888', 'iphonex' ]  data type:  object
    //查看键值对的数量
    client.hlen('phone', cb); //err:  null  data:  2  data type:  number
    //删掉其中一个键值对
    client.hdel('phone', 'price', cb); //err:  null  data:  1  data type:  number
    //看看price是否还在?
    client.hmget('phone', 'price', cb); //err:  null  data:  [ null ]  data type:  object,原来只留下了null
    //再加几个属性
    client.hmset('phone', 'vendor', 'apple', 'madein', 'china', cb);
    //取出所有的键值对
    client.hgetall('phone', cb); //err:  null  data:  { name: 'iphonex', vendor: 'apple', madein: 'china' }  data type:  object
    //取出所有的键
    client.hkeys('phone', cb); //err:  null  data:  [ 'name', 'vendor', 'madein' ]  data type:  object
    //取出所有的值
    client.hvals('phone', cb); //err:  null  data:  [ 'iphonex', 'apple', 'china' ]  data type:  object
    //判断键是否存在
    client.hexists('phone', 'name', cb); //err:  null  data:  1  data type:  number
    client.hexists('phone', 'price', cb); //err:  null  data:  0  data type:  number
    

    Native Promises

    If you are using node v8 or higher, you can promisify node_redis with util.promisify as in:

    const {promisify} = require('util');
    const getAsync = promisify(client.get).bind(client);
    

    now getAsync is a promisified version of client.get:

    // We expect a value 'foo': 'bar' to be present
    // So instead of writing client.get('foo', cb); you have to write:
    return getAsync('foo').then(function(res) {
        console.log(res); // => 'bar'
    });
    

    or using async await:

    async myFunc() {
        const res = await getAsync('foo');
        console.log(res);
    }
    

    reference :

    https://github.com/NodeRedis/node_redis

    https://segmentfault.com/a/1190000014681783?utm_source=tag-newest

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  • 原文地址:https://www.cnblogs.com/wangjiale1024/p/11359844.html
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