Reactors

The reactors plugin runs live mutations. A live mutation is a stored mutation definition with live true and an optional integer priority. Enable it at open with plugins {reactors {}}. It has no settings. See plugin selection for the open options.

Store live mutations with patch_definition under the mutations kind. After each commit, every live mutation evaluates its query as of that transaction. Their patches commit together as one output transaction, completing a round. When patches write different values to one path, the higher priority wins. Equal priorities fail with Reactor_Conflict. The combined patch must satisfy the scoped schemas of every contributing live mutation. A schema rejection records Schema_Validation and commits no output. A failure keeps the cursor before its source transaction until a live mutation definition changes.

Runtime status

Call status to inspect these fields:

Field	Contents
`enabled`	Whether the plugin is enabled
`cursor`	Last processed source transaction
`head`	Current database head
`pending`	Whether processing remains
`reactors`	Live mutations, each with `id`, `name`, `priority` and `sinceTx`
`failure`	Current failure, with `sourceTx`, `code`, `reactors` and `path`; absent when no failure stands

When to call sync

Live mutations run automatically after commits. Your write can finish before a live mutation has produced its output. Call sync before a read that depends on that output. For example, a live mutation can add greeted after a person is created. A read immediately after creation can miss greeted. Synchronize the reactors before asserting that result in a test. Applications that can observe the output later can let the runtime continue in the background.

Its options accept only the common maxWait option. Success covers source transactions committed before the call. Later transactions can still have pending rounds. A failed round reports failed and appears in status.

Operations

Operation	Returns	Summary
status	Unavailable	reactors.status() returns the reactor runtime's owned status document.
sync	Unavailable	reactors.sync(options) waits until live mutations processed the commits made before the call.