redis on mac

on mac

1. install

        $ brew install redis
   

2. start redis-server

        $ redis-server
   

3. start redis-cli

        $ redis-cli
   

4. demo

   1. simple

       > set gree2 hqlgree2
       OK
       > get gree2
       "hqlgree2"
       > keys g*
       1) "gree2"
      

   2. mset

       > mset first "value 1" second "value 2"
       OK
       > mget first second
       1) "value 1"
       2) "value 2"
      

   3. ttl

       # >0 seconds
       # -2 key is expired or does not exist
       # -1 exist but no expiration time set
      
       > set gree2 hqlgree2
       > set gree2 hqlgree2
       OK
       > expire gree2 10
       (integer) 1
       > ttl gree2
       (integer) 4
       > ttl gree2
       (integer) 0
       > ttl gree2
       (integer) -1
       > ttl gree2
       (integer) -1
       > get gree2
       (nil)
      

   4. incr

       > set counter 100
       OK
       > incr counter
       (integer) 101
       > incrby counter 5
       (integer) 106
       > incr counter
       (integer) 107
       > decr counter
       (integer) 106
       > decrby counter 100
       (integer) 6
       > get counter
       "6"
       > incrbyfloat counter 2.4
       "8.4"
      

node.js demo

1. install redis for node.js

        $ npm install redis
        redis@1.0.0 node_modules/redis
   

2. demo 1

   1. touch hello.js

       $ pico hello.js
       var redis = require("redis");
       var client = redis.createClient();
       client.set("gree2", "hqlgree2 from node.js");
       client.get("gree2", redis.print);
       client.quit();
      

   2. run hello.js

       $ node hello.js
       "hqlgree2 from node.js"
      

3. demo 2

   1. touch vote.js

       $ pico vote.js
       var redis = require("redis");
       var client = redis.createClient();
       client.set("article:100:headline", "hqlgree2's book one");
       client.set("article:135:headline", "hqlgree2's book two");
      
       function upVote(id){
           var key = "article:" + id + ":votes";
           client.incr(key);
       }
      
       function downVote(id){
           var key = "article:" + id + ":votes";
           client.decr(key);
       }
      
       function showResults(id){
           var headlineKey = "article:" + id + ":headline";
           var voteKey = "article:" + id + ":votes";
           client.mget([headlineKey, voteKey], function(err, replies){
               console.log('the article "' + replies[0] + '" has', replies[1], 'votes');
           });
       }
      
       upVote(100);
       upVote(100);
       upVote(100);
       upVote(135);
       upVote(135);
       downVote(135);
      
       showResults(100);
       showResults(135);
      
       client.quit();
      

   2. run

       $ node vote.js
       the article "hqlgree2's book one" has 9 votes
       the article "hqlgree2's book two" has 3 votes