Redis学习指南

一、数据结构

• string(字符串)
• list(列表)
• set(集合)
• hash(散列)
• zset(有序集合)

二、命令列表

2.1 Redis Strings

> set mykey somevalueOK> get mykey"somevalue"

> set counter 100OK> incr counter(integer) 101> incr counter(integer) 102> incrby counter 50(integer) 152

> mset a 10 b 20 c 30OK> mget a b c1) "10"2) "20"3) "30"

> set mykey helloOK> exists mykey(integer) 1> del mykey(integer) 1> exists mykey(integer) 0

> set mykey xOK> type mykeystring> del mykey(integer) 1> type mykeynone

> set key some-valueOK> expire key 5(integer) 1> get key (immediately)"some-value"> get key (after some time)(nil)

> set key 100 ex 10OK> ttl key(integer) 9

2.2 Redis Lists

> rpush mylist A(integer) 1> rpush mylist B(integer) 2> lpush mylist first(integer) 3> lrange mylist 0 -11) "first"2) "A"3) "B"

> rpush mylist 1 2 3 4 5 "foo bar"(integer) 9> lrange mylist 0 -11) "first"2) "A"3) "B"4) "1"5) "2"6) "3"7) "4"8) "5"9) "foo bar"

> rpush mylist a b c(integer) 3> rpop mylist"c"> rpop mylist"b"> rpop mylist"a"

> rpush mylist 1 2 3 4 5(integer) 5> ltrim mylist 0 2OK> lrange mylist 0 -11) "1"2) "2"3) "3"

> brpop tasks 51) "tasks"2) "do_something"

2.3 Redis Hashes

> hmset user:1000 username antirez birthyear 1977 verified 1OK> hget user:1000 username"antirez"> hget user:1000 birthyear"1977"> hgetall user:10001) "username"2) "antirez"3) "birthyear"4) "1977"5) "verified"6) "1"

> hmget user:1000 username birthyear no-such-field1) "antirez"2) "1977"3) (nil)

> hincrby user:1000 birthyear 10(integer) 1987> hincrby user:1000 birthyear 10(integer) 1997

2.4 Redis Sets

> sadd myset 1 2 3(integer) 3> smembers myset1. 32. 13. 2

2.5 Redis Sorted Sets

> zadd hackers 1940 "Alan Kay"(integer) 1> zadd hackers 1957 "Sophie Wilson"(integer) 1> zadd hackers 1953 "Richard Stallman"(integer) 1> zadd hackers 1949 "Anita Borg"(integer) 1> zadd hackers 1965 "Yukihiro Matsumoto"(integer) 1> zadd hackers 1914 "Hedy Lamarr"(integer) 1> zadd hackers 1916 "Claude Shannon"(integer) 1> zadd hackers 1969 "Linus Torvalds"(integer) 1> zadd hackers 1912 "Alan Turing"(integer) 1?> zrange hackers 0 -11) "Alan Turing"2) "Hedy Lamarr"3) "Claude Shannon"4) "Alan Kay"5) "Anita Borg"6) "Richard Stallman"7) "Sophie Wilson"8) "Yukihiro Matsumoto"9) "Linus Torvalds"

三、应用示例

3.1 分布式锁

需要安装nuget包：StackExchange.Redis。

using StackExchange.Redis;using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;?namespace Redlock.CSharp{    public class Lock    {?        public Lock(RedisKey resource, RedisValue val, TimeSpan validity)        {            this.resource = resource;            this.val = val ;            this.validity_time = validity;        }?        private RedisKey resource;?        private RedisValue val;?        private TimeSpan validity_time;?        public RedisKey Resource { get { return resource; } }?        public RedisValue Value { get { return val; } }?        public TimeSpan Validity { get { return validity_time; } }    }}?

using StackExchange.Redis;using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading;using System.Threading.Tasks;?namespace Redlock.CSharp{    public class Redlock    {?        public Redlock(params ConnectionMultiplexer[] list)        {             foreach(var item in list)                this.redisMasterDictionary.Add(item.GetEndPoints().First().ToString(),item);        }?        const int DefaultRetryCount = 3;        readonly TimeSpan DefaultRetryDelay = new TimeSpan(0, 0, 0, 0, 200);        const double ClockDriveFactor = 0.01;?        protected int Quorum { get { return (redisMasterDictionary.Count / 2) + 1; } }?        /// <summary>        /// String containing the Lua unlock script.        /// </summary>        const String UnlockScript = @"            if redis.call(""get"",KEYS[1]) == ARGV[1] then                return redis.call(""del"",KEYS[1])            else                return 0            end";??        protected static byte[] CreateUniqueLockId()        {            return Guid.NewGuid().ToByteArray();        }??        protected Dictionary<String,ConnectionMultiplexer> redisMasterDictionary = new Dictionary<string,ConnectionMultiplexer>();?        //TODO: Refactor passing a ConnectionMultiplexer        protected bool LockInstance(string redisServer, string resource, byte[] val, TimeSpan ttl)        {                        bool succeeded;            try            {                var redis = this.redisMasterDictionary[redisServer];                succeeded = redis.GetDatabase().StringSet(resource, val, ttl, When.NotExists);            }            catch (Exception)            {                succeeded = false;            }            return succeeded;        }?        //TODO: Refactor passing a ConnectionMultiplexer        protected void UnlockInstance(string redisServer, string resource, byte[] val)        {            RedisKey[] key = { resource };            RedisValue[] values = { val };            var redis = redisMasterDictionary[redisServer];            redis.GetDatabase().ScriptEvaluate(                UnlockScript,                 key,                values                );        }?        public bool Lock(RedisKey resource, TimeSpan ttl, out Lock lockObject)        {            var val = CreateUniqueLockId();            Lock innerLock = null;            bool successfull = retry(DefaultRetryCount, DefaultRetryDelay, () =>            {                try                {                    int n = 0;                    var startTime = DateTime.Now;?                    // Use keys                    for_each_redis_registered(                        redis =>                        {                            if (LockInstance(redis, resource, val, ttl)) n += 1;                        }                    );?                    /*                     * Add 2 milliseconds to the drift to account for Redis expires                     * precision, which is 1 millisecond, plus 1 millisecond min drift                      * for small TTLs.                             */                    var drift = Convert.ToInt32((ttl.TotalMilliseconds * ClockDriveFactor) + 2);                    var validity_time = ttl - (DateTime.Now - startTime) - new TimeSpan(0, 0, 0, 0, drift);?                    if (n >= Quorum && validity_time.TotalMilliseconds > 0)                    {                        innerLock = new Lock(resource, val, validity_time);                        return true;                    }                    else                    {                        for_each_redis_registered(                            redis =>                            {                                UnlockInstance(redis, resource, val);                            }                        );                        return false;                    }                }                catch (Exception)                { return false; }            });?            lockObject = innerLock;            return successfull;        }?        protected void for_each_redis_registered(Action<ConnectionMultiplexer> action)        {            foreach (var item in redisMasterDictionary)            {                action(item.Value);            }        }?        protected void for_each_redis_registered(Action<String> action)        {            foreach (var item in redisMasterDictionary)            {                action(item.Key);            }        }?        protected bool retry(int retryCount, TimeSpan retryDelay, Func<bool> action)        {            int maxRetryDelay = (int)retryDelay.TotalMilliseconds;            Random rnd = new Random();            int currentRetry = 0;?            while (currentRetry++ < retryCount)            {                if (action()) return true;                Thread.Sleep(rnd.Next(maxRetryDelay));            }            return false;        }?        public void Unlock(Lock lockObject)        {            for_each_redis_registered(redis =>                {                    UnlockInstance(redis, lockObject.Resource, lockObject.Value);                });        }?        public override string ToString()        {            StringBuilder sb = new StringBuilder();            sb.AppendLine(this.GetType().FullName);?            sb.AppendLine("Registered Connections:");            foreach(var item in redisMasterDictionary)            {                sb.AppendLine(item.Value.GetEndPoints().First().ToString());            }?            return sb.ToString();        }    }}?

原文地址：https://www.cnblogs.com/xsddxz/p/11288242.html