RethinkDB binding spec

Detailed documentation on the RethinkDB binding component


The RethinkDB state store supports transactions which means it can be used to support Dapr actors. Dapr persists only the actor’s current state which doesn’t allow the users to track how actor’s state may have changed over time.

To enable users to track change of the state of actors, this binding leverages RethinkDB’s built-in capability to monitor RethinkDB table and event on change with both the old and new state. This binding creates a subscription on the Dapr state table and streams these changes using the Dapr input binding interface.

Setup Dapr component

Create the following YAML file and save this to the components directory in your application directory. (Use the --components-path flag with dapr run to point to your custom components dir)

kind: Component
  name: changes
  type: bindings.rethinkdb.statechange
  version: v1
  - name: address
    value: <REPLACE-RETHINKDB-ADDRESS> # Required, e.g. or rethinkdb.default.svc.cluster.local:28015).
  - name: database
    value: <REPLACE-RETHINKDB-DB-NAME> # Required, e.g. dapr (alpha-numerics only)

For example on how to combine this binding with Dapr Pub/Sub to stream state changes to a topic see here.

Last modified January 30, 2021: Update (#1118) (10c2d21)