Seed Dump

Seed Dump is a Rails 4 and 5 plugin that adds a rake task named db:seed:dump.

It allows you to create seed data files from the existing data in your database.

You can also use Seed Dump from the Rails console. See below for usage examples.

Installation

Add it to your Gemfile with:

gem 'seed_dump', git: 'git://github.com/renuo/seed_dump', branch: 'master'

Documentation

This documentation is point to the develop branch of the repository. For the documentation of the current release head to: https://github.com/renuo/seed_dump/blob/master/README.md.

Examples

Rake task

Dump all data directly to db/seeds.rb:

  $ rake db:seed:dump

Result:

Product.create!([
  { category_id: 1, description: "Long Sleeve Shirt", name: "Long Sleeve Shirt" },
  { category_id: 3, description: "Plain White Tee Shirt", name: "Plain T-Shirt" }
])
User.create!([
  { password: "123456", username: "test_1" },
  { password: "234567", username: "test_2" }
])

Dump only data from the users table and dump a maximum of 1 record:

$ rake db:seed:dump MODELS=User LIMIT=1

Result:

User.create!([
  { password: "123456", username: "test_1" }
])

Append to db/seeds.rb instead of overwriting it:

rake db:seed:dump APPEND=true

Use another output file instead of db/seeds.rb:

rake db:seed:dump FILE=db/seeds/users.rb

Exclude name and age from the dump:

rake db:seed:dump EXCLUDE=name,age

There are more options that can be set— see below for all of them.

Console

Output a dump of all User records:

irb(main):001:0> puts SeedDump.dump(User)
User.create!([
  { password: "123456", username: "test_1" },
  { password: "234567", username: "test_2" }
])

Write the dump to a file:

irb(main):002:0> SeedDump.dump(User, file: 'db/seeds.rb')

Append the dump to a file:

irb(main):003:0> SeedDump.dump(User, file: 'db/seeds.rb', append: true)

Exclude name and age from the dump:

irb(main):004:0> SeedDump.dump(User, exclude: [:name, :age])

Options are specified as a Hash for the second argument.

In the console, any relation of ActiveRecord rows can be dumped (not individual objects though)

irb(main):001:0> puts SeedDump.dump(User.where(is_admin: false))
User.create!([
  { password: "123456", username: "test_1", is_admin: false },
  { password: "234567", username: "test_2", is_admin: false }
])

Options

Option	Values	Usage	Default
append	[true, false]	Set if the data should be appended to the file or overwritten	false
batch_size	[Integer]	Number of records written to the file at once. Decrease if you are running out of memory, Increase if too slow	1000
limit	[Integer]	Limits the number of entries dumped into the seeds file	no
file	[Path]	Sets the file path for the output seeds file	'db/seeds.rb'
exclude	[Columns]	Exclude multiple attributes from the dump	[:id, :created_at, :updated_at]
import	[true, false]	Use the format for the activerecord-import gem	false
conditions	[]	Dump only specific records to the seeds. Can be set in the console with (e.g. `SeedDump.dump(User.where(state: :active))`)	None
models	[Models]	List of models that should be dumped to the seeds	All Models
models_excluded	[Models]	List of modles that should be excluded from the seeds dump	No Models excluded
insert_all	[true, false]	Set if the data should use insert_all instead of create! in the dump	false