You are viewing the documentation for Blueriq 16. Documentation for other versions is available in our documentation directory.

Introduction

The Key-Value store API provides a minimum set of operations that are needed by the Blueriq Runtime in order to interact with a generic key-value store. It also enhances the Blueriq Runtime to be able to run in a clustered configuration.

A default implementation of the Key-Value Store API based on Redis is provided by Blueriq, named Redis Key-Value Store Component.

This chapter describes how to enable the default component and how to add a custom implementation for a key value store.

Redis Key-Value Store Component

Prerequisites

An instance of Redis server needs to run on a node and needs to be accessible from the Blueriq Runtime.

Depending on the linux distribution, a Redis package may be available from the repository in any case consult their official documentation here.

Redis does not officially support Windows. However, the Microsoft Open Tech group develops and maintains this Windows port targeting Win64. More information here.


Enable/Disable

In order to enable the component, the profile "keyvalue-redis-store" profile must be added in the bootstrap.properties

spring.profiles.active=native,keyvalue-redis-store

Properties

The Redis Key-Value Store Component defines the following properties used for 9. Concurrency Control on Multiple Nodes:

PropertyDescriptionRequiredDefault Value
blueriq.keyvalue-redis-store.subscription-pool.typeThe thread pool type to use for the keyspace notifications subscription thread pool.FALSECACHED
blueriq.keyvalue-redis-store.subscription-pool.thread-name-prefixThe thread name prefix used for threads in the keyspace notifications subscription thread pool.FALSEkeyspace-subscription-
blueriq.keyvalue-redis-store.subscription-pool.thread-countIndicates how many threads should be created when using FIXED thread pools.FALSE0

blueriq.keyvalue-redis-store.task-pool.type

The thread pool type to use for the keyspace notifications task thread pool. FALSEFIXED
blueriq.keyvalue-redis-store.task-pool.thread-name-prefixThe thread name prefix used for threads in the keyspace notifications subscription thread pool. FALSEkeyspace-task-
blueriq.keyvalue-redis-store.task-pool.thread-countIndicates how many threads should be created when using FIXED thread pools.FALSE4


The Redis Key-Value Store Component uses the following default Spring Boot properties in order to connect to Redis:

PropertyDescriptionRequiredDefault Value
spring.data.redis.hostThe DNS name or IP address of the Redis serverTRUE
spring.data.redis.portThe port on which to connect to RedisFALSE6379
spring.data.redis.passwordThe password used to connect to Redis. Can be left empty if no password is required.FALSE


The following example configuration connects the Runtime to a Redis instance running on localhost on the default port and using a password:

spring.data.redis.host=localhost
spring.data.redis.password=example


Using the key-value store in custom plug-ins

Blueriq provides an IKeyValueStore interface which can be used to interact with a generic key-value store. In order to use this interface, add blueriq-component-api to your project's dependencies:

<dependency>
  <groupId>com.blueriq</groupId>
  <artifactId>blueriq-component-api</artifactId>
  <version>${blueriq.version}</version>
</dependency>


Then, inject the IKeyValueStore in your components:

@Component
public class ExampleComponent {
 
  private final IKeyValueStore keyValueStore;
 
  public ExampleComponent(IKeyValueStore keyValueStore) {
    this.keyValueStore = keyValueStore;
  }
 
  public void operation() {
    keyValueStore.set(namespacedKey("key"), "value");
  }
 
  private String namespacedKey(String key) {
    return "example" + keyValueStore.getNamespaceSeparator() + key;
  }
}

Note that we recommend using namespaces for your keys, in order to keep them separate from keys used by Blueriq or Spring Session. The root namespace used by Blueriq is "blueriq". The root namespace used by Spring Session is "spring". 

If you would like to hide the namespace logic, the NamespacedKeyValueStore implementation may be used, available in the blueriq-runtime artifact. The code example below writes the same "example:key" key in the key-value store, but without having to explicitly prefix the key with a namespace every time:

@Component
public class ExampleComponent {
 
  private final IKeyValueStore keyValueStore;
 
  public ExampleComponent(IKeyValueStore keyValueStore) {
    this.keyValueStore = new NamespacedKeyValueStore(keyValueStore, "example");
  }
 
  public void operation() {
    keyValueStore.set("key", "value");
  }
}


Using other key-value store implementations

It is possible to replace the default Redis-based key-value store implementation with an implementation that uses another type of key-value store.

How to create your own implementation is documented here.