Tair (Redis® OSS-Compatible):Use a client to connect to an instance

The following sample project is created by using Maven. You can also manually download the Jedis client.

1. Open the compiler and create a project.

2. Add the following code to the pom.xml file.

   In this example, Jedis 4.3.0 is used.

   <dependency>
       <groupId>redis.clients</groupId>
       <artifactId>jedis</artifactId>
       <version>4.3.0</version>
   </dependency>

3. Enter the following code in the editor and modify the code based on the comments:

   import redis.clients.jedis.Jedis;
   import redis.clients.jedis.JedisPool;
   import redis.clients.jedis.JedisPoolConfig;
   
   public class JedisExample {
       public static void main(String[] args) {
           JedisPoolConfig config = new JedisPoolConfig();
           // Specify the maximum number of idle connections based on your business requirements. This value cannot exceed the maximum number of connections supported by the instance. 
           config.setMaxIdle(200);
           // Specify the maximum number of connections based on your business requirements. This value cannot exceed the maximum number of connections supported by the instance. 
           config.setMaxTotal(300);
           config.setTestOnBorrow(false);
           config.setTestOnReturn(false);
           // Replace the values of the host and password parameters with the endpoint of the instance and the password of the instance account. 
           String host = "r-bp1s1bt2tlq3p1****pd.redis.rds.aliyuncs.com";
           // If you use the default account, directly enter the password. If you use a custom account, enter the password in the <Username>:<Password> format. For example, if the username of the custom account is testaccount and the password is Rp829dlwa, enter testaccount:Rp829dlwa as the password. 
           String password = "r-bp1s1bt2tlq3p1****:Database123";
           JedisPool pool = new JedisPool(config, host, 6379, 3000, password);
           Jedis jedis = null;
           try {
               jedis = pool.getResource();
               // Refer to the following example to perform related operations: 
               jedis.set("foo10", "bar");
               System.out.println(jedis.get("foo10"));
               jedis.zadd("sose", 0, "car");
               jedis.zadd("sose", 0, "bike");
               System.out.println(jedis.zrange("sose", 0, -1));
           }
           catch (Exception e) {
               // Handle timeout errors or other exceptions. 
               e.printStackTrace();
           }
           finally {
               if (jedis != null) {
                   jedis.close();
               }
           }
           pool.destroy();    // If your application exits and you want to destroy the resources, call this method. This way, the connection is closed, and the resources are released. 
       }
   }

4. Run the preceding code. The following output is expected on successful completion:

   bar
   [bike, car]

   Important

   If specific parameters are improperly configured or some features are improperly used, errors may occur. For more information about how to troubleshoot the errors, see Common errors and troubleshooting.

1. Download and install the PhpRedis client.

2. Enter the following code in the PHP editor and modify the code based on the comments.

   In this example, PHP 8.2.1 and PhpRedis 5.3.7 are used.

   <?php
    /* Replace the values of the host and port parameters with the endpoint and port number of the instance.   */
    $host = "r-bp10noxlhcoim2****.redis.rds.aliyuncs.com";
    $port = 6379;
    /* Replace the values of the user and pwd parameters with the username and password of the instance account. */
    $user = "testaccount";
    $pwd = "Rp829dlwa";
    $redis = new Redis();
    if ($redis->connect($host, $port) == false) {
            die($redis->getLastError());
      }
    if ($redis->auth([$user, $pwd]) == false) {
            die($redis->getLastError());
     }
     /* You can perform operations on the instance after the connection is established. The following code provides an example on how to call the set and get methods:   */
    if ($redis->set("foo", "bar") == false) {
            die($redis->getLastError());
    }
    $value = $redis->get("foo");
    echo $value;
    ?>

3. Run the preceding code to connect to the instance.

   Note

   Common errors and solutions:

   • Cannot assign requested address: For information about the cause of and solution to the error, see What do I do if the "Cannot assign requested address" error is returned when I access ApsaraDB for Redis over short-lived connections?

   • redis protocol error, got ' ' as reply type byte: Update the version of your PhpRedis client. For more information, visit GitHub.

1. Download and install the redis-py client.

2. Enter the following code in the Python editor and modify the code based on the comments.

   In this example, Python 3.9 and redis-py 4.4.1 are used.

   #!/usr/bin/env python
   #-*- coding: utf-8 -*-
   import redis
   # Replace the values of the host and port parameters with the endpoint and port number of the instance. 
   host = 'r-bp10noxlhcoim2****.redis.rds.aliyuncs.com'
   port = 6379
   # Replace the value of the pwd parameter with the password of the instance account. 
   # If you use the default account, directly enter the password. If you use a custom account, enter the password in the <Username>:<Password> format. For example, if the username of the custom account is testaccount and the password is Rp829dlwa, enter testaccount:Rp829dlwa as the password. 
   pwd = 'testaccount:Rp829dlwa'
   r = redis.Redis(host=host, port=port, password=pwd)
   # You can perform operations on the instance after the connection is established. The following code provides an example on how to call the set and get methods: 
   r.set('foo', 'bar')
   print(r.get('foo'))

3. Run the preceding code to connect to the instance.

The following sample project is created by using Maven. You can also manually download the Lettuce or Jedis client.

1. Open the compiler and create a project.

2. Add the following dependencies to the pom.xml file and download the Lettuce or Jedis client.

   Important

   If you use Lettuce, we recommend that you use 6.3.0.RELEASE or later and configure the TCP_USER_TIMEOUT parameter. This prevents blackhole filtering on the Lettuce client.

   <?xml version="1.0" encoding="UTF-8"?>
   <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
       <modelVersion>4.0.0</modelVersion>
       <parent>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-parent</artifactId>
           <version>2.4.2</version>
           <relativePath/> <!-- lookup parent from repository -->
       </parent>
       <groupId>com.aliyun.tair</groupId>
       <artifactId>spring-boot-example</artifactId>
       <version>0.0.1-SNAPSHOT</version>
       <name>spring-boot-example</name>
       <description>Demo project for Spring Boot</description>
       <properties>
           <java.version>1.8</java.version>
       </properties>
       <dependencies>
           <dependency>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-starter-web</artifactId>
           </dependency>
           <dependency>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-starter-test</artifactId>
               <scope>test</scope>
           </dependency>
           <dependency>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-starter-data-redis</artifactId>
           </dependency>
           <dependency>
               <groupId>redis.clients</groupId>
               <artifactId>jedis</artifactId>
           </dependency>
           <dependency>
               <groupId>io.lettuce</groupId>
               <artifactId>lettuce-core</artifactId>
               <version>6.3.0.RELEASE</version>
           </dependency>
           <dependency>
               <groupId>io.netty</groupId>
               <artifactId>netty-transport-native-epoll</artifactId>
               <version>4.1.100.Final</version>
               <classifier>linux-x86_64</classifier>
           </dependency>
       </dependencies>
       <build>
           <plugins>
               <plugin>
                   <groupId>org.springframework.boot</groupId>
                   <artifactId>spring-boot-maven-plugin</artifactId>
               </plugin>
           </plugins>
       </build>
   </project>

3. Enter the following code in the Spring Data Redis editor and modify the code based on the comments.

   In this example, Spring Data Redis 2.4.2 is used.

   • Spring Data Redis With Jedis

     @Bean
          JedisConnectionFactory redisConnectionFactory() {
              RedisStandaloneConfiguration config = new RedisStandaloneConfiguration("host", port);
      
              JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
              // Specify the maximum number of connections based on your business requirements. This value cannot exceed the maximum number of connections supported by the instance. 
              jedisPoolConfig.setMaxTotal(30);
              // Specify the maximum number of idle connections based on your business requirements. This value cannot exceed the maximum number of connections supported by the instance. 
              jedisPoolConfig.setMaxIdle(20);
              // Disable testOn[Borrow|Return] to prevent additional PING commands from being generated. 
              jedisPoolConfig.setTestOnBorrow(false);
              jedisPoolConfig.setTestOnReturn(false);
      
              JedisClientConfiguration jedisClientConfiguration = JedisClientConfiguration.builder().usePooling().poolConfig(
                  jedisPoolConfig).build();
      
              return new JedisConnectionFactory(config, jedisClientConfiguration);
          }

   • Spring Data Redis with Lettuce (including configuration of the TCP_USER_TIMEOUT parameter)

     @Configuration
     public class BeanConfig {
         /**
          * Enable TCP keepalive and configure the following three parameters:
          *  TCP_KEEPIDLE = 30
          *  TCP_KEEPINTVL = 10
          *  TCP_KEEPCNT = 3
          */
         private static final int TCP_KEEPALIVE_IDLE = 30;
     
         /**
          * The TCP_USER_TIMEOUT parameter can avoid situations where Lettuce remains stuck in a continuous timeout loop during a failure or crash event. 
          * refer: https://github.com/lettuce-io/lettuce-core/issues/2082
          */
         private static final int TCP_USER_TIMEOUT = 30;
     
         @Bean
         LettuceConnectionFactory redisConnectionFactory() {
             RedisStandaloneConfiguration config = new RedisStandaloneConfiguration();
             config.setHostName("r-bp1y4is8svonly****pd.redis.rds.aliyuncs.com");
             config.setPort(6379);
             config.setUsername("r-bp1y4is8svonly****");
             config.setPassword("Da****3");
     
             // Config TCP KeepAlive
             SocketOptions socketOptions = SocketOptions.builder()
                 .keepAlive(KeepAliveOptions.builder()
                     .enable()
                     .idle(Duration.ofSeconds(TCP_KEEPALIVE_IDLE))
                     .interval(Duration.ofSeconds(TCP_KEEPALIVE_IDLE / 3))
                     .count(3)
                     .build())
                 .tcpUserTimeout(TcpUserTimeoutOptions.builder()
                     .enable()
                     .tcpUserTimeout(Duration.ofSeconds(TCP_USER_TIMEOUT))
                     .build())
                 .build();
             LettuceClientConfiguration lettuceClientConfiguration = LettuceClientConfiguration.builder().clientOptions(
                 ClientOptions.builder().socketOptions(socketOptions).build()).build();
             return new LettuceConnectionFactory(config, lettuceClientConfiguration);
         }
     
         @Bean
         RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
             RedisTemplate<String, Object> template = new RedisTemplate<>();
             template.setConnectionFactory(connectionFactory);
             return template;
         }
     }

4. Run the preceding code to connect to the instance.

1. Download and install hiredis.

2. Enter the following code in the C or C ++ editor and modify the code based on the comments.

   In this example, hiredis 1.1.0 is used.

   #include <stdio.h>
   #include <stdlib.h>
   #include <string.h>
   #include <hiredis.h>
   int main(int argc, char **argv) {
       unsigned int j;
       redisContext *c;
       redisReply *reply;
       if (argc < 4) {
               printf("Usage: example r-bp10noxlhcoim2****.redis.rds.aliyuncs.com 6379 instance_id password\n");
               exit(0);
       }
       const char *hostname = argv[1];
       const int port = atoi(argv[2]);
       const char *instance_id = argv[3];
       const char *password = argv[4];
       struct timeval timeout = { 1, 500000 }; // 1.5 seconds
       c = redisConnectWithTimeout(hostname, port, timeout);
       if (c == NULL || c->err) {
       if (c) {
               printf("Connection error: %s\n", c->errstr);
               redisFree(c);
       } else {
           printf("Connection error: can't allocate redis context\n");
       }
       exit(1);
       }
       /* AUTH */
       reply = redisCommand(c, "AUTH %s", password);
       printf("AUTH: %s\n", reply->str);
       freeReplyObject(reply);
       /* PING server */
       reply = redisCommand(c,"PING");
       printf("PING: %s\n", reply->str);
       freeReplyObject(reply);
       /* Set a key */
       reply = redisCommand(c,"SET %s %s", "foo", "hello world");
       printf("SET: %s\n", reply->str);
       freeReplyObject(reply);
       /* Set a key using binary safe API */
       reply = redisCommand(c,"SET %b %b", "bar", (size_t) 3, "hello", (size_t) 5);
       printf("SET (binary API): %s\n", reply->str);
       freeReplyObject(reply);
       /* Try a GET and two INCR */
       reply = redisCommand(c,"GET foo");
       printf("GET foo: %s\n", reply->str);
       freeReplyObject(reply);
       reply = redisCommand(c,"INCR counter");
       printf("INCR counter: %lld\n", reply->integer);
       freeReplyObject(reply);
       /* again ... */
       reply = redisCommand(c,"INCR counter");
       printf("INCR counter: %lld\n", reply->integer);
       freeReplyObject(reply);
       /* Create a list of numbers, from 0 to 9 */
       reply = redisCommand(c,"DEL mylist");
       freeReplyObject(reply);
       for (j = 0; j < 10; j++) {
               char buf[64];
               snprintf(buf,64,"%d",j);
               reply = redisCommand(c,"LPUSH mylist element-%s", buf);
               freeReplyObject(reply);
           }
       /* Let's check what we have inside the list */
       reply = redisCommand(c,"LRANGE mylist 0 -1");
       if (reply->type == REDIS_REPLY_ARRAY) {
               for (j = 0; j < reply->elements; j++) {
               printf("%u) %s\n", j, reply->element[j]->str);
       }
       }
       freeReplyObject(reply);
       /* Disconnects and frees the context */
       redisFree(c);
       return 0;
   }

3. Compile the code.

   gcc -o example -g example.c -I /usr/local/include/hiredis -lhiredis

4. Perform a test run and connect to the instance.

    ./example r-bp10noxlhcoim2****.redis.rds.aliyuncs.com 6379 r-bp10noxlhcoim2**** password

1. Download and install StackExchange.Redis 2.7.20 or later. For more information, see Notice on update of StackExchange.Redis.

   Important

   We recommend that you do not use the ServiceStack Redis or CSRedis client.

   • If you use ServiceStack Redis and run into issues related to the client, you must purchase technical support from ServiceStack.

   • The support for the CSRedis client has been ended.

2. Enter the following code in the StackExchange.Redis editor and modify the code based on the comments.

   In this example, StackExchange.Redis 2.7.20 is used.

   using StackExchange.Redis;
    // Specify the endpoint, port number, and password of the instance. 
    private static ConfigurationOptions configurationOptions = ConfigurationOptions.Parse("r-bp10noxlhcoim2****.redis.rds.aliyuncs.com:6379,password=testaccount:Rp829dlwa,connectTimeout=2000");
     //the lock for singleton
    private static readonly object Locker = new object();
     //singleton
    private static ConnectionMultiplexer redisConn;
    //singleton
    public static ConnectionMultiplexer getRedisConn()
    {
        if (redisConn == null)
        {
            lock (Locker)
            {
                if (redisConn == null || !redisConn.IsConnected)
                {
                    redisConn = ConnectionMultiplexer.Connect(configurationOptions);
                }
            }
        }
        return redisConn;
    }

   Note

   • ConfigurationOptions is a core object of the StackExchange.Redis client. ConfigurationOptions is shared and reused by the client. The singleton pattern is recommended. For more information about parameter settings, see Configuration Options.

   • GetDatabase() returns a lightweight object. You can obtain this object from the ConnectionMultiplexer object.

      redisConn = getRedisConn();
      var db = redisConn.GetDatabase();

3. Use the client to perform operations on common data structures. Examples:

   String

   //set get
   string strKey = "hello";
   string strValue = "world";
   bool setResult = db.StringSet(strKey, strValue);
   Console.WriteLine("set " + strKey + " " + strValue + ", result is " + setResult);
   //incr
   string counterKey = "counter";
   long counterValue = db.StringIncrement(counterKey);
   Console.WriteLine("incr " + counterKey + ", result is " + counterValue);
   //expire
   db.KeyExpire(strKey, new TimeSpan(0, 0, 5));
   Thread.Sleep(5 * 1000);
   Console.WriteLine("expire " + strKey + ", after 5 seconds, value is " + db.StringGet(strKey));
   //mset mget
   KeyValuePair<RedisKey, RedisValue> kv1 = new KeyValuePair<RedisKey, RedisValue>("key1", "value1");
   KeyValuePair<RedisKey, RedisValue> kv2 = new KeyValuePair<RedisKey, RedisValue>("key2", "value2");
   db.StringSet(new KeyValuePair<RedisKey, RedisValue>[] {kv1,kv2});            
   RedisValue[] values = db.StringGet(new RedisKey[] {kv1.Key, kv2.Key});
   Console.WriteLine("mget " + kv1.Key.ToString() + " " + kv2.Key.ToString() + ", result is " + values[0] + "&&" + values[1]);

   Hash

   string hashKey = "myhash";
   //hset
   db.HashSet(hashKey,"f1","v1");
   db.HashSet(hashKey,"f2", "v2");
   HashEntry[] values = db.HashGetAll(hashKey);
   //hgetall
   Console.Write("hgetall " + hashKey + ", result is");
   for (int i = 0; i < values.Length;i++) 
   {
     HashEntry hashEntry = values[i];
     Console.Write(" " + hashEntry.Name.ToString() + " " + hashEntry.Value.ToString());
   }
   Console.WriteLine();

   List

   //list key
   string listKey = "myList";
   //rpush
   db.ListRightPush(listKey, "a");
   db.ListRightPush(listKey, "b");
   db.ListRightPush(listKey, "c");
   //lrange
   RedisValue[] values = db.ListRange(listKey, 0, -1);
   Console.Write("lrange " + listKey + " 0 -1, result is ");
   for (int i = 0; i < values.Length; i++)
   {
    Console.Write(values[i] + " ");
   }
   Console.WriteLine();

   Set

   //set key
   string setKey = "mySet";
   //sadd
   db.SetAdd(setKey, "a");
   db.SetAdd(setKey, "b");
   db.SetAdd(setKey, "c");
   //sismember
   bool isContains = db.SetContains(setKey, "a");
   Console.WriteLine("set " + setKey + " contains a is " + isContains );

   Sorted Set

   string sortedSetKey = "myZset";
   //sadd
   db.SortedSetAdd(sortedSetKey, "xiaoming", 85);
   db.SortedSetAdd(sortedSetKey, "xiaohong", 100);
   db.SortedSetAdd(sortedSetKey, "xiaofei", 62);
   db.SortedSetAdd(sortedSetKey, "xiaotang", 73);
   //zrevrangebyscore
   RedisValue[] names = db.SortedSetRangeByRank(sortedSetKey, 0, 2, Order.Ascending);
   Console.Write("zrevrangebyscore " + sortedSetKey + " 0 2, result is ");
   for (int i = 0; i < names.Length; i++)
   {
     Console.Write(names[i] + " ");
   }
   Console.WriteLine();

1. Download and install the node-redis client.

2. Enter the following code in the node-redis client and modify the code based on the comments.

   In this example, Node.js 19.4.0 and node-redis 4.5.1 are used.

   import { createClient } from 'redis';
   
   // Specify the port number, endpoint, username, and password of the instance.
   const client = createClient({
     // redis[s]://[[username][:password]@][host][:port][/db-number]
     url: 'redis://testaccount:Rp829dlwa@r-bp10noxlhcoim2****.redis.rds.aliyuncs.com:6379'
   });
   
   client.on('error', (err) => console.log('Redis Client Error', err));
   
   await client.connect();
   
   await client.set('foo', 'bar');
   const value = await client.get('foo');
   console.log("get foo: %s", value);
   await client.disconnect();

   Note

   If the SyntaxError: Cannot use import statement outside a module error message is returned, change the suffix of the .js file to .mjs and add the --experimental-modules option when you use this client. Example: node --experimental-modules redis.mjs.

3. Run the preceding code to connect to the instance.

1. Download and install the go-redis client.

2. Enter the following code in the go-redis client and modify the code based on the comments.

   In this example, Go 1.18.5 and go-redis 8.11.5 are used.

   package main
   
   import (
   	"github.com/go-redis/redis"
   	"fmt"
   )
   
   func ExampleClient() {
   	client := redis.NewClient(&redis.Options{
           // Specify the endpoint and port number of the instance.
   		Addr:     "r-bp10noxlhcoim2****.redis.rds.aliyuncs.com:6379",
           // Specify the password of the instance account.
   		Password: "testaccount:Rp829dlwa",
   		DB:       0,  // use default DB
   	})
       // The following code provides an example on how to call the set and get methods: 
   	err := client.Set("foo", "bar", 0).Err()
   	if err != nil {
   		panic(err)
   	}
   
   	val, err := client.Get("foo").Result()
   	if err != nil {
   		panic(err)
   	}
   	fmt.Println("set : foo -> ", val)
   }
   
   func main() {
   	ExampleClient()
   }

3. Run the preceding code to connect to the instance.