Skip to main content
A seed is a class implementing ISeed, registered with @decorator.seed(). The decorator adds the class to the container and to the seeds registry, so the runner can resolve, filter, and order it. run() populates the database, and the other members decide whether — and when — it runs.

​
Scaffold a seed

Generate a seed with the CLI. talos seed:create writes a seed class under modules/<module>/src/seeds/, an accompanying .yml data file, and a matching test under modules/<module>/tests/seeds/, then regenerates the seeds.ts barrel export and creates the module’s bin/seed/run.ts runner if it is missing. 
# Generate a seed in the shared module (prompts for the name)
talos seed:create

# Name the seed and target a module
talos seed:create --name=DemoUser --module=blog
OptionDescriptionDefault
--nameName of the seed. Normalized to PascalCase with a Seed suffix.Prompted if omitted
--moduleModule the seed is created in.shared
The generated class loads its data from the sibling .yml file and is ready to fill in: 
import { decorator, type Environment, type ISeed, type SeedClassType } from "@talosjs/seeds";
import data from "./demo-user-seed.yml";

@decorator.seed()
export class DemoUserSeed implements ISeed {
  public async run<T>(): Promise<T> {
    // Your seed logic here
    console.log(data);

    return data as T;
  }

  public isActive(): boolean {
    return true;
  }

  public async getDependencies(): Promise<SeedClassType[]> {
    return [];
  }

  public getEnv(): Environment[] {
    return [];
  }
}
See the seed:create command for the full reference.

​
Implement run()

Fill in run() with the inserts that populate the database. Keep the records in the sibling .yml file and import them, so data stays separate from logic. Whatever run() returns is passed to any seed that depends on this one, so return the records a dependent seed needs to reference.

​
Gate the seed

Three members decide whether the seed runs:
  • isActive() — return false to skip the seed entirely. Use it to disable a seed without deleting it.
  • getEnv() — return the environments the seed targets (for example [Environment.Development, Environment.Test]). An empty list runs in every environment; a non-empty list runs only when the current APP_ENV is included.
  • getDependencies() — return the seed classes that must run first. Each dependency is resolved from the container and run before this seed, and its return value is passed into this seed’s run(data).
public getDependencies(): SeedClassType[] {
  return [UserSeed];
}

public getEnv(): Environment[] {
  return [Environment.Development, Environment.Test];
}

​
Next steps

  • Running seeds: populate the database with talos seed:run.
  • Caching: how a seed’s run is cached and invalidated.