The settings service provides functionality for other services to register new settings as well as storing and retrieving the respective settings' values.

The settings service is currently used for managing the:

users' profile settings like the language and the email notification settings,
possible user roles and their respective permissions,
assignment of roles to users.

As an example, user profile settings that can be changed in the Web UI must be persistent.

The settings service supports two different backends for persisting the data. The backend can be set via the SETTINGS_STORE_TYPE environment variable. Supported values are:

metadata: The default. This backend persists the settings data via the storage-system service.
filesystem: This backend persists the settings data in a directory on the local filesystem. The directory can be configured with SETTINGS_DATA_PATH. This backend is not suitable for running multiple intances of the settings service in a scale-out deployment and should be therefore considered deprecated.

Caching

When using SETTINGS_STORE_TYPE=metadata, the settings service caches the results of queries against the storage backend to provide faster responses. The content of this cache is independent of the cache used in the storage-system service as it caches directory listing and settings content stored in files.

The store used for the cache can be configured using the SETTINGS_CACHE_STORE environment variable. Possible stores are:

memory: Basic in-memory store and the default.
redis: Stores metadata in a configured Redis cluster.
redis-sentinel: Stores metadata in a configured Redis Sentinel cluster.
etcd: Stores metadata in a configured etcd cluster.
nats-js: Stores metadata using the key-value-store feature of nats jetstream
noop: Stores nothing. Useful for testing. Not recommended in production environments.

Note that in-memory stores are by nature not reboot-persistent.
Though usually not necessary, a database name can be configured for event stores if the event store supports this. Generally not applicable for stores of type in-memory, redis and redis-sentinel. These settings are blank by default which means that the standard settings of the configured store apply.
The settings service can be scaled if not using in-memory stores and the stores are configured identically over all instances.
When using redis-sentinel, the Redis master to use is configured via SETTINGS_CACHE_STORE_NODES in the form of <sentinel-host>:<sentinel-port>/<redis-master> like 10.10.0.200:26379/mymaster.

Settings Management

Infinite Scale services can register settings bundles with the settings service.

Settings Usage

Services can set or query ocis setting values of a user from settings bundles.