platform/packages/model/src/utils.ts

import { Class, Data, Doc, DocumentUpdate, Ref, Space, TxOperations } from '@anticrm/core'
import { deepEqual } from 'fast-equals'

function toUndef (value: any): any {
  return value === null ? undefined : value
}

function diffAttributes (doc: Data<Doc>, newDoc: Data<Doc>): DocumentUpdate<Doc> {
  const result: DocumentUpdate<any> = {}
  const allDocuments = new Map(Object.entries(doc))
  const newDocuments = new Map(Object.entries(newDoc))

  for (const [key, value] of allDocuments) {
    const newValue = toUndef(newDocuments.get(key))
    if (!deepEqual(newValue, toUndef(value))) {
      // update is required, since values are different
      result[key] = newValue
    }
  }
  for (const [key, value] of newDocuments) {
    const oldValue = toUndef(allDocuments.get(key))
    if (oldValue === undefined && value !== undefined) {
      // Update with new value.
      result[key] = value
    }
  }
  return result
}

/**
 * @public
 */
export async function createOrUpdate<T extends Doc> (client: TxOperations, _class: Ref<Class<T>>, space: Ref<Space>, data: Data<T>, _id: Ref<T>): Promise<void> {
  const existingDoc = await client.findOne<Doc>(_class, { _id })
  if (existingDoc !== undefined) {
    const { _class: _oldClass, _id, space: _oldSpace, modifiedBy, modifiedOn, ...oldData } = existingDoc
    const updateOp = diffAttributes(oldData, data)
    if (Object.keys(updateOp).length > 0) {
      await client.update(existingDoc, updateOp)
    }
  } else {
    await client.createDoc<T>(_class, space, data, _id)
  }
}