Redis

cosid-spring-redis stores segment counters and machine id leases in Redis, through the application's Spring Data Redis connection (StringRedisTemplate):

• SpringRedisIdSegmentDistributor: segment counters, one key per generator, cosid:{namespace.name}.adder.
• SpringRedisMachineLeaseStore: machine id leases in a cosid:{namespace}:lease hash, next to the keys 3.4 used. Lease times come from the Redis TIME command.

Keys carry a hash tag ({...}), so Redis Cluster works: all keys of one counter or one namespace land in one slot.

Installation

Gradle (Kotlin)

dependencies {
    implementation(platform("me.ahoo.cosid:cosid-bom:$cosidVersion"))
    implementation("me.ahoo.cosid:cosid-spring-boot-starter")
    implementation("me.ahoo.cosid:cosid-spring-redis")
    implementation("org.springframework.boot:spring-boot-starter-data-redis")
}

Maven

<dependencies>
    <dependency>
        <groupId>me.ahoo.cosid</groupId>
        <artifactId>cosid-spring-boot-starter</artifactId>
    </dependency>
    <dependency>
        <groupId>me.ahoo.cosid</groupId>
        <artifactId>cosid-spring-redis</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-redis</artifactId>
    </dependency>
</dependencies>

Configuration

spring:
  data:
    redis:
      host: localhost # the connection CosId uses
cosid:
  namespace: ${spring.application.name}
  machine:
    enabled: true # for Snowflake IDs and CosIdGenerator
    distributor:
      type: redis
  segment:
    enabled: true # for segment IDs
    distributor:
      type: redis

Property	Default	Description
cosid.segment.distributor.redis.timeout	1s	Each segment command; 0 disables it
cosid.machine.distributor.redis.timeout	1s	Lease renewal and release; must be positive
cosid.machine.distributor.redis.distribute-timeout	10s	Each command of the claim at startup, whose first command also pays for connecting; must be positive

Persistence

A counter that goes back after Redis restarts without its data hands out IDs a second time. Run Redis with AOF persistence (appendonly yes), or use another store for segments.

See CosId-Example-Redis for a runnable application.