Function getCachedPublicKey

getCachedPublicKey(
    serviceId: string,
    version: number,
    builders: RascalConfigBuilder[],
    keyServiceBaseUrl: string,
    getTokenCallback: GetEventSigningTokenFunc,
    logger?: Logger,
): Promise<string>
Retrieves a public key for specific service ID and version. If not available in the cache - cache is updated using cachePublicSigningKeys and cache is checked again. If even still there is no matching key - error is thrown, because at this point, if there is a need to validate the received event - it is expected for the service that produced said event to register its own public key with the Key Service.
Parameters
- serviceId: string
  ID of the service that signed event originated from
- version: number
  Version of the public key of the service that signed event originated from
- builders: RascalConfigBuilder[]
  Used to determine which events the service is expecting to receive. Passing a list of all builders used by setupMessagingBroker is recommended.
- keyServiceBaseUrl: string
  Base URL of Mosaic Key Service
- getTokenCallback: GetEventSigningTokenFunc
  Function to retrieve authorization token result to make a request to the Key Service
- Optionallogger: Logger
  Optional instance of the Mosaic Logger. If not provided - new instance will be created and used by the function itself.
Returns Promise<string>