Make a factory

A factory builds complete rows for tests, so a test sets only the fields it is about. It writes through the model, so callbacks, constraints and meta run in a fixture as they do in production. sdxc make factory writes one in database/factories/ for the model of the same name:

sdxc make factory post

Wrote database/factories/post.ts

sdxc make model already writes a model's factory, with a sample value per field. Reach for sdxc make factory for a model made with --skip factory, or one written by hand.

Flags

A factory is test code itself, so it never gets a test beside it.

What it writes

import { defineFactory } from "@sdxc/data-model/testing";

import { Post } from "~/app/models/post";

/** A complete Post row; a test overrides only the fields it is about. */
export const PostFactory = defineFactory(Post, {});

The factory imports the model's PascalCase export from the file of the same name in app/models/, so sdxc make factory billing/invoice writes database/factories/billing/invoice.ts reading Invoice from ~/app/models/billing/invoice, the name sdxc make model exports. With no fields to read, the attributes start empty for you to fill.

Fill it in

Give every column the model requires a value, drawn from the sample streams so each row differs and a seed reproduces a run:

export const PostFactory = defineFactory(Post, {
	title: ({ sample }) => sample.lorem.sentence(),
	body: ({ sample }) => sample.lorem.paragraph(),
	published_at: () => Date.now(),
	author_id: async ({ create }) => (await create(AuthorFactory)).id,
}).trait("draft", { published_at: null });

Then create rows in a test:

let factories = createFactories(models, { seed: 42 });
let post = await factories.create(PostFactory, { title: "Hello" });
await factories.createMany(PostFactory, 3);

Data models covers traits, sequences and the in-memory database a test binds the models to, and Test data seeding beyond one model.

Where to go next

• Make a model — the model a factory writes through.

• Make a migration — the table the rows land in.

• Generate files — the flags, configuration and stubs every kind shares.