Playback model APIs | WorkSpec documentation

The playback helpers resolve authored tasks and interactions without a renderer.

Create a reusable model

createPlaybackModel(documentValue) normalizes the input for repeated playback queries.

JavaScript

const {
  createPlaybackModel,
  getObjectStateAtTime
} = require("workspec");

const model = createPlaybackModel(startingState);
const state = getObjectStateAtTime(model, "worker_1", 550);

Query helpers

Function	Return value
`resolveWorldStateAtTime(documentOrModel, time)`	Resolved objects grouped by ID and type
`getObjectAtTime(documentOrModel, objectId, time)`	Resolved object or `null`
`getObjectStateAtTime(documentOrModel, objectId, time)`	`properties.state` or `undefined`
`getObjectLocationAtTime(documentOrModel, objectId, time)`	Location ID or `null`

The helper converts time with Number(time). Pass a numeric minute value for predictable playback queries.

Playback boundary

These pure helpers resolve authored playback data. They do not accept an authoritative WorkSpecRun.

Use runtime.snapshotRunAt() when Changes or Generator execution produced the state.

resolveObjectStateAtTime() is a compatibility helper. Do not use it in new integrations.