RedisCache

Distributed cache that stores values in Redis in-memory database.

Implements: ICache, IReferenceable, IConfigurable, IOpenable

Description

The RedisCache class allows you to create distributed caches that store values in Redis in-memory database.

Configuration parameters

  • connection(s):
    • discovery_key: (optional) key to retrieve the connection from IDiscovery
    • host: host name or IP address
    • port: port number
    • uri: resource URI or connection string with all parameters in it
  • credential(s):
    • store_key: key to retrieve parameters from ICredentialStore
    • username: username (currently is not used)
    • password: user’s password
  • options:
    • retries: number of retries (default: 3)
    • timeout: default caching timeout in milliseconds (default: 1 minute)
    • max_size: maximum number of values stored in this cache (default: 1000)

References

  • *:discovery:*:*:1.0 - (optional) IDiscovery services
  • *:credential-store:*:*:1.0 - (optional) ICredentialStore stores to resolve credentials

Constructors

Creates a new instance of this cache.

public constructor()

Instance methods

close

Closes a component and frees used resources.

public close(context: IContext): Promise<void>

  • context: IContext - (optional) a context to trace execution through a call chain.

configure

Configures a component by passing its configuration parameters.

public configure(config: ConfigParams): void

  • config: ConfigParams - configuration parameters to be set.

isOpen

Checks if the component is open.

public isOpen(): boolean

  • returns: boolean - true if the component is open and false otherwise.

open

Opens the component.

public open(context: IContext): Promise<void>

  • context: IContext - (optional) a context to trace execution through a call chain.

remove

Removes a value from the cache by its key.

public remove(context: IContext, key: string): Promise<any>

  • context: IContext - (optional) a context to trace execution through a call chain.
  • key: string - unique value key.
  • returns: Promise<any> - removed value.

retrieve

Retrieves a cached value from the cache using its key. If the value is missing in the cache or expired, it returns null.

public retrieve(context: IContext, key: string): Promise<any>

  • context: IContext - (optional) a context to trace execution through a call chain.
  • key: string - unique value key.
  • returns: Promise<any> - retrieved cached value or null if nothing was found.

setReferences

Sets references to dependent components.

public setReferences(references: IReferences): void

  • references: IReferences - references to locate the component dependencies.

store

Stores a value in the cache with an expiration time.

public store(context: IContext, key: string, value: any, timeout: number): Promise<any>

  • context: IContext - (optional) a context to trace execution through a call chain.
  • key: string - unique value key.
  • value: any - value to store.
  • timeout: number - expiration timeout in milliseconds.
  • returns: Promise<any> - stored value.

Examples

let cache = new RedisCache();
cache.configure(ConfigParams.fromTuples(
  "host", "localhost",
  "port", 6379
));

await cache.open("123");
await cache.store("123", "key1", "ABC");
let value = await cache.store("123", "key1"); // Result: "ABC"