RedisCache

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.

RedisCache()

Fields

Instance methods

close

Closes a component and frees used resources.

@override

Future close(String? correlationId)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.

configure

Configures a component by passing its configuration parameters.

@override

void configure(ConfigParams config)

• config: ConfigParams - configuration parameters to be set.

isOpen

Checks if the component is open.

@override

bool isOpen()

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

open

Opens the component.

@override

Future open(String? correlationId)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.

remove

Removes a value from the cache by its key.

@override

Future<dynamic> remove(String? correlationId, String key)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.
• key: String - unique value key.
• returns: Future<dynamic> - 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.

@override

Future<dynamic> retrieve(String? correlationId, String key)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.
• key: String - unique value key.
• returns: Future<dynamic> - retrieved cached value or null if nothing was found.

setReferences

Sets references to dependent components.

@override

void setReferences(IReferences references)

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

store

Stores a value in the cache with an expiration time.

Future<dynamic> store(String? correlationId, String key, value, int timeout)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.
• key: String - unique value key.
• value: dynamic - value to store.
• timeout: int - expiration timeout in milliseconds.
• returns: Future<dynamic> - stored value.

Examples

var cache = RedisCache();
cache.configure(ConfigParams.fromTuples([
   "host", "localhost",
   "port", 6379
]));

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