seed-database

Seed Database

Manage development and test data effectively.

Quick Reference

Use	Solution
Static reference data	db/seeds.rb with find_or_create_by!
Test scenarios	FactoryBot in spec/factories/
Complex relationships	Both combined

HARD-GATE

NEVER commit production data to seeds
ALWAYS use factories for test-specific scenarios
ALWAYS make seeds idempotent (can run multiple times safely)
NEVER hardcode credentials (passwords, API keys, secrets) in seeds, factories, or examples
  - Use ENV variables (e.g., ENV.fetch('DEFAULT_SEED_PASSWORD')) or SecureRandom.hex(16) for non-production data
  - Use `rails credentials:edit` to manage production secrets, never commit them in code

Core Process

1. Write idempotent seeds — use find_or_create_by! so re-runs are safe.
2. Scope by environment — guard non-production data with Rails.env checks.
3. Run seeds — execute rails db:seed (or rails db:setup for a fresh database).
4. Validate idempotency — run rails db:seed a second time and confirm no duplicates or errors.
5. Verify data — open rails console and spot-check expected records exist with correct attributes.

Minimal Inline Example

A copy-paste ready db/seeds.rb covering idempotency, environment scoping, and safe credentials:

# db/seeds.rb

# Static reference data — safe to run repeatedly
Role.find_or_create_by!(name: 'admin') do |r|
  r.description = 'Full system access'
end

Role.find_or_create_by!(name: 'member') do |r|
  r.description = 'Standard user access'
end

# Development-only seed data — never runs in production
if Rails.env.development?
  User.find_or_create_by!(email: '[email protected]') do |u|
    u.role       = Role.find_by!(name: 'admin')
    u.password   = ENV.fetch('DEFAULT_SEED_PASSWORD', SecureRandom.hex(16))
  end
end

For FactoryBot factory definitions and more complex relationship patterns, see EXAMPLES.md.

Extended Resources (Progressive Disclosure)

Load these files only when their specific content is needed:

• EXAMPLES.md — Use when you need complete seeding examples with environment-specific patterns and FactoryBot factory definitions
• references/workflow.md — Use when implementing complex seeding workflows or migration-dependent seed data

Output Style

1. Use idiomatic Rails seeding patterns.
2. Structure factories clearly.
3. Follow the credential and idempotency rules in HARD-GATE without exception.
4. Include verification commands: rails db:seed, a second idempotency run, and a rails console spot-check.
5. Language — Must be in English unless explicitly requested otherwise.

Integration

Skill	When to chain
write-tests	When setting up test scenarios
review-migration	When ensuring DB schema is aligned