defineSeederConfig

defineSeederConfig is a tiny identity helper for your seeder.config.ts. It returns its argument unchanged, but typed as SeederConfig — so you get autocomplete, inline docs, and compile-time errors while you write the file.

import { defineSeederConfig } from '@ackplus/nest-seeder';

export default defineSeederConfig({
  imports: [/* ...Nest modules */],
  providers: [/* ...optional providers */],
  seeders: [/* ...seeder classes */],
});

It's optional

The CLI happily loads a plain default-exported object too. defineSeederConfig exists purely for the editor experience — wrapping your config gives you type-checking and IntelliSense with zero runtime cost.

Signature

function defineSeederConfig(config: SeederConfig): SeederConfig;

It simply returns config as-is. There is no magic — the value you pass is the value you get back.

The `SeederConfig` shape

A config object describes the NestJS context your seeders run in, plus optional default run options.

interface SeederConfig {
  // Nest modules to bootstrap (DB connection, ConfigModule, forFeature, etc.)
  imports?: any[];

  // Extra providers to register in the seeding context
  providers?: any[];

  // Seeder classes to run, in order (top-to-bottom on seed, reverse on refresh)
  seeders?: any[];

  // Default run options (each can be overridden by a CLI flag)
  refresh?: boolean;
  dryRun?: boolean;
  continueOnError?: boolean;
  name?: string | string[];
  context?: Record<string, any>;
}

SeederConfig vs SeederModuleOptions

These describe the same shape. SeederConfig is what you author in seeder.config.ts; the same options flow into SeederModule.register() when you wire seeding up inside an app. The run options (refresh, dryRun, continueOnError, name, context) mirror SeederServiceOptions and let you set defaults that CLI flags can override.

Fields

Field	Type	Description
`imports`	`any[]`	Nest modules to bootstrap — your DB connection, `ConfigModule`, `TypeOrmModule.forFeature`, etc.
`providers`	`any[]`	Optional extra providers available for injection inside seeders.
`seeders`	`any[]`	Seeder classes to run. They execute top-to-bottom; on `--refresh` they drop in reverse.
`refresh`	`boolean`	Default for "drop then reseed". Overridden by `--refresh`.
`dryRun`	`boolean`	Default for dry-run mode. Overridden by `--dry-run`.
`continueOnError`	`boolean`	Keep going if a seeder throws. Overridden by `--continue-on-error`.
`name`	`string \| string[]`	Restrict to specific seeders by class name or `@SeederName`. Overridden by `--name`.
`context`	`Record<string, any>`	Arbitrary data forwarded to every seeder as `options.context`. Overridden by `--context`.

Order matters for foreign keys

List parents first. Seeders run in array order, and --refresh drops them in reverse — so children are removed before their parents, keeping foreign keys happy.

Before / after

The only difference is the type information your editor sees. Both files behave identically at runtime.

Plain objectdefineSeederConfig

import { TypeOrmModule } from '@nestjs/typeorm';
import { User } from './src/database/entities/user.entity';
import { UserSeeder } from './src/database/seeders/user.seeder';

// No type safety — typos and wrong shapes slip through silently.
export default {
  imports: [TypeOrmModule.forFeature([User])],
  seeders: [UserSeeder],
};

import { TypeOrmModule } from '@nestjs/typeorm';
import { defineSeederConfig } from '@ackplus/nest-seeder';
import { User } from './src/database/entities/user.entity';
import { UserSeeder } from './src/database/seeders/user.seeder';

// Fully typed — autocomplete on every field, errors on typos.
export default defineSeederConfig({
  imports: [TypeOrmModule.forFeature([User])],
  seeders: [UserSeeder],
});

With the wrapped version, misspelling a key (e.g. seeder instead of seeders) or passing the wrong type is caught by TypeScript right in your editor.

Full example

A complete TypeORM config at the project root:

import { TypeOrmModule } from '@nestjs/typeorm';
import { defineSeederConfig } from '@ackplus/nest-seeder';
import { User } from './src/database/entities/user.entity';
import { UserSeeder } from './src/database/seeders/user.seeder';

export default defineSeederConfig({
  imports: [
    TypeOrmModule.forRoot({
      type: 'postgres',
      host: process.env.DB_HOST ?? 'localhost',
      port: Number(process.env.DB_PORT ?? 5432),
      username: process.env.DB_USERNAME ?? 'postgres',
      password: process.env.DB_PASSWORD ?? 'postgres',
      database: process.env.DB_DATABASE ?? 'app',
      entities: [User],
      synchronize: true,
    }),
    TypeOrmModule.forFeature([User]),
  ],
  seeders: [UserSeeder],
});

Setting default run options

You can bake in defaults that the CLI flags still override:

import { defineSeederConfig } from '@ackplus/nest-seeder';

export default defineSeederConfig({
  imports: [/* ... */],
  seeders: [/* ... */],

  // Defaults — overridable from the CLI
  continueOnError: true,
  context: { environment: 'development' },
});

Running nest-seed --context '{"environment":"staging"}' would override the context above for that run.

defineSeederConfig ​

Signature ​

The SeederConfig shape ​

Fields ​

Before / after ​

Full example ​

Setting default run options ​

See also ​