Terms or components

The following terms and components are introduced with the Notification Service.

Kafka cluster

A set of machines which are all part of a Kafka environment. The Kafka cluster receives notifications from the Notification Service and then stores them in categories called topics. Individual notifications can be sent to specific subsets of the total cluster, depending on how the cluster is configured.

Topic

A string (249 alphanumeric, -, _, and . characters) that represents a stream of notifications. Producers always send notifications to a topic on a Kafka cluster. A topic is a first in, first out queue of notifications.

Notification

A Kafka record that represents a single write or delete event of an object. Each notification consists of a key, a payload, and a timestamp. The notification is in JSON text.

Producer

A process that writes notifications to a topic on a Kafka cluster.

Consumer

A process that reads notifications from a topic on a Kafka cluster.

Notification key

The part of the notification that is used by the Kafka producer to select which nodes in the Kafka cluster to send the notification to. The key is in JSON text.

Notification payload

The part of the notification that describes the event that occurred. The payload is in JSON text.

Intent

A small, temporary object that is stored in the Cloud Object Storage System. To improve performance, and because of their typically short storage lifespan, they are usually stored in memory on the Slicestor® devices. The intent is fully protected by the IDA of the vault to which it is written.

Retry agent

A software process that runs on the Accesser® devices to retry any notifications that failed to send.