class Planter::Seeder

Class that seeders should inherit from. Seeders should be in db/seeds, and named TABLE_seeder.rb, where TABLE is the name of the table being seeded (I.E. users_seeder.rb). If your seeder is named differently than the table, you'll need to specify the table with the model option. The seeder's class name should be the same as the file name, but camelized. So, UsersSeeder. The directory where the seeder files are located can be changed via an initializer.

The most basic way to seed is to have a CSV file with the same name as the table in db/seed_files/. So, users.csv. This CSV should have the table's column names as header. To seed using this method, your class should look like the following. Note that :csv_name and :model are only required if your seeder or csv are named differently than the table being seeded. The directory where the seed files are kept can be changed via an initializer.

# db/seeds/users_seeder.rb
require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :csv, csv_name: :users, model: 'User'
end

Another way to seed is to create records from a data array. To do this, your class must implement a data attribute or method, which is an array of hashes. Note that this class already provides the attr_reader for this attribute, so the most you have to do is create instance variables in your constructor. If if you want your data to be different for each new record (via Faker, +Array#sample+, etc.), you'll probably want to supply a method called data that returns an array of new data each time.

require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :data_array
  def data
    [{foo: 'bar', baz: 'bar'}]
  end
end

In both of the above methods, you can specify a parent association, which is the belongs_to association name in your model, which, when specified, records will be created for each record in the parent table. For example, if we're seeding the users table, and the model is User, which belongs to Person, then doing the following will create a user record for each record in the Person table. Note that nothing is automatically done to prevent any validation errors; you must do this on your own, mostly likely using Faker or a similar library.

require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :data_array, parent: :person
  def data
    [{foo: 'bar', baz: 'bar'}]
  end
end

You can also set number_of_records to determine how many times each record in the data array will get created. The default is 1. Note that if this attribute is set alongside parent, number_of_records will be how many records will be created for each record in the parent table.

require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :data_array, number_of_records: 5
  def data
    [{foo: 'bar', baz: 'bar'}]
  end
end

By default, all fields are used to look up the record. If it already exists, it is not re-created. If you have specific fields that a record should be looked-up by, you can pass the unique_columns option. This will attempt to look up the record by those fields only, and if one doesn't exist, one will be created with the rest of the attributes. An example of when this would be useful is with Devise; you can't pass password in the create method, so specifying unique_columns on everything except password allows it to be passed as an attribute to the first_or_create call.

require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :data_array, unique_columns: %i[username email]
  def data
    [{username: 'foo', email: 'bar', password: 'Example'}]
  end
end

If you need to seed a different way, put your own custom seed method in your seeder class and do whatever needs to be done.

Constants

SEEDING_METHODS

The allowed seeding methods.

@return [Array]

Attributes

data[R]

Array of hashes used to create records. Your class must set this attribute when using data_array seeding method, although it's probably more likely that you'll want to define a method that returns a new set of data each time (via Faker, +Array#sample+, etc.). When using csv, data will be set to the data within the csv. You can override this.

@return [Array]

transformations[R]

A hash of user-defined column names and procs to be run on values. This is most useful for when seeding from csv, and you need to transform, say, 'true' (String) into true (Boolean). The user may define this as an instance variable, or define a method that returns the hash.

When defining a Proc/Lambda, you can make it accept 0, 1, or 2 arguments.

  • When 0, the value is replaced by the result of the Lambda.

  • When 1, the value is passed to the Lambda, and is subsequently replaced by the result of the Lambda.

  • When 2, the value is the first argument, and the entire row, as a Hash, is the second argument. This allows for more complicated transformations that can be dependent on other fields and values in the record.

@return [Hash, nil]

@example

class UsersSeeder < Planter::Seeder
  seeding_method :csv
  def transformations
    {
      admin: ->(v) { v == 'true' },
      last_name: ->(value, row) { "#{value} #{row[:suffix]}".squish }
    }
  end
end

Public Class Methods

seeding_method( seed_method, number_of_records: 1, model: nil, parent: nil, csv_name: nil, unique_columns: nil, erb_trim_mode: nil ) click to toggle source

If your class is going to use the inherited seed method, you must tell it which seeding_method to use. The argument to this method must be included in the SEEDING_METHODS array.

@param [Symbol] seed_method

@kwarg [Integer] number_of_records

@kwarg [String] model

@kwarg [Symbol, String] parent

@kwarg [Symbol, String] csv_name

@kwarg [Symbol, String] unique_columns

@kwarg [String] erb_trim_mode

@example

require 'planter'
class UsersSeeder < Planter::Seeder
  seeding_method :csv,
    number_of_records: 2,
    model: 'User'
    parent: :person,
    csv_name: :awesome_users,
    unique_columns %i[username email],
    erb_trim_mode: '<>'
end
# File lib/planter/seeder.rb, line 212
def self.seeding_method(
  seed_method,
  number_of_records: 1,
  model: nil,
  parent: nil,
  csv_name: nil,
  unique_columns: nil,
  erb_trim_mode: nil
)
  unless SEEDING_METHODS.include?(seed_method.intern)
    raise ArgumentError, "Method must be: #{SEEDING_METHODS.join(', ')}"
  end

  self.seed_method = seed_method
  self.number_of_records = number_of_records
  self.model = model || to_s.delete_suffix('Seeder').singularize
  self.parent = parent
  self.csv_name = csv_name || to_s.delete_suffix('Seeder').underscore
  self.erb_trim_mode = erb_trim_mode || Planter.config.erb_trim_mode
  self.unique_columns =
    case unique_columns
    when String, Symbol then [unique_columns.intern]
    when Array then unique_columns.map(&:intern)
    end
end

Public Instance Methods

csv_name() click to toggle source

The csv file corresponding to the model.

@return [String]

# File lib/planter/seeder.rb, line 174
class_attribute :csv_name
erb_trim_mode() click to toggle source

What trim mode should ERB use?

@return [String]

# File lib/planter/seeder.rb, line 138
class_attribute :erb_trim_mode
model() click to toggle source

The model for the table being seeded. If the model name you need is different, change via seeding_method.

@return [String]

# File lib/planter/seeder.rb, line 152
class_attribute :model
number_of_records() click to toggle source

The number of records to create from each record in the data array. If nil, defaults to 1, but you can override this in your class via seeding_method.

@return [Integer]

# File lib/planter/seeder.rb, line 168
class_attribute :number_of_records
parent() click to toggle source

The model of the parent. When provided with association, records in the data array, will be created for each record in the parent table. Your class must set this attribute via seeding_method.

@return [String]

# File lib/planter/seeder.rb, line 160
class_attribute :parent
seed() click to toggle source

The default seed method. To use this method, your class must provide a valid seeding_method, and not implement its own seed method.

# File lib/planter/seeder.rb, line 241
def seed
  validate_attributes
  extract_data_from_csv if seed_method == :csv

  parent ? create_records_from_parent : create_records
end
seed_method() click to toggle source

The seeding method specified.

@return [Symbol]

# File lib/planter/seeder.rb, line 180
class_attribute :seed_method
unique_columns() click to toggle source

When creating a record, the fields that will be used to look up the record. If it already exists, a new one will not be created.

@return [Array]

# File lib/planter/seeder.rb, line 145
class_attribute :unique_columns