Factories and seeders

@veap/database includes defineFactory, the Factory base class, Seeder, and runSeeders. Use them for repeatable local data and test fixtures—not as a substitute for production data migrations.

Define a factory#

import { defineFactory } from "@veap/database";
import { Article } from "../models/Article.js";

export const ArticleFactory = defineFactory(Article, () => ({
  title: "Example article",
  slug: `example-${crypto.randomUUID()}`,
  body: "Fixture content",
  published: false,
}));

The factory helper returns a callable factory constructor with methods such as count, state, sequence, make, makeOne, create, and createOne.

• make / makeOne instantiate model objects without saving.
• create / createOne persist model objects.
• state applies an object override or a transformation callback.
• sequence rotates through a list of attribute objects.
• count(n) requests multiple model instances.

const draft = await ArticleFactory.makeOne({ published: false });
const published = await ArticleFactory.count(3).create({ published: true });

Use unique slugs and other unique fields when creating multiple records.

Create a seeder#

import { Seeder } from "@veap/database";

export class ArticleSeeder extends Seeder {
  async run(): Promise<void> {
    await ArticleFactory.count(5).create();
  }
}

Then run the seeder after the database has been initialized:

import { runSeeders } from "@veap/database";
import { ArticleSeeder } from "./ArticleSeeder.js";

await runSeeders(ArticleSeeder, { inTransaction: true });

runSeeders accepts a seeder class or an array of classes. Seeders run sequentially. The optional inTransaction setting wraps the run in a single database transaction.

Safety#

• Do not run destructive seeders automatically in production.
• Keep reference-data seeding separate from schema migrations.
• Make fixtures deterministic when tests depend on exact values.
• Ensure the schema is migrated before factories execute.