Typed function to use with knex tables, to remove some columns from provided object.

knex-typed-clip-columns.ts

import 'types/schemas/knex-tables'
import { Tables } from 'knex/types/tables'

type TableColumns<TTableName extends keyof Tables = keyof Tables> = {
  [T in TTableName]: (keyof Tables[T]['base'])[]
}

const deleteColumns: Partial<TableColumns> = {
  users: ['name'],
}

export function clipColumns<
  TTableName extends keyof Tables,
  TRecord extends Tables[TTableName]['insert'] | Tables[TTableName]['update'],
>(tableName: TTableName, record: TRecord | TRecord[]): TRecord | TRecord[] {
  const columnsToRemove = deleteColumns[tableName] || []

  const clipSingleRecord = (rec: TRecord): TRecord => {
    const result = { ...rec }
    for (const column of columnsToRemove) {
      delete result[column]
    }
    return result
  }

  if (Array.isArray(record)) {
    return record.map(clipSingleRecord)
  } else {
    return clipSingleRecord(record)
  }
}