Authoring Transforms

Write per-step transforms in tables/NNN/transform.ts using defineTransformMap<PrevCM, NextCM>. Omitted entities use the default chain: prev.removeKeys → next.addKeys.

Example

import { defineTransformMap } from '@karmaniverous/entity-client-dynamodb/get-dotenv';
import type { ConfigMap as PrevCM } from '../001/entityManager';
import type { ConfigMap as NextCM } from './entityManager';

export default defineTransformMap<PrevCM, NextCM>({
  user: async (record, { prev, next }) => {
    const item = prev.removeKeys('user', record); // storage -> domain
    // Optional domain changes here...
    return next.addKeys('user', item); // domain -> storage
  },
});

Semantics

undefined → drop the record
single item/record → migrate one
array of items/records → fan-out (same entity token)
Cross-entity fan-out is not supported in v1.

Performance knobs

--transform-concurrency controls transform parallelism within a page (default 1).
Unprocessed items on writes are retried by EntityClient batch utilities.

Authoring Transforms

Settings

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