Dibber

A set of tools to tidy up rails seeds.rb files.

Dibber has two compoments:

Seeder

Seeder is designed to simplify the process of pulling attributes from YAML files, and populating ActiveRecord objects with those attributes.

ProcessLog

ProcessLog provides Seeder with a simple before and after reporting tool.

Installation

Add this to your Gemfile:

gem 'dibber'

Rails Examples

You have a rails app with a Thing model, and you want to seed it with some things. Thing instances have the attributes ‘name’, ‘colour’, ‘size’. You have a YAML file ‘db/seeds/things.yml’ that looks like this:

foo:
  colour: red
  size: large

bar:
  colour: blue
  size: small

Add this to your ‘db/seeds.rb’

Seeder = Dibber::Seeder
Seeder.seed :thing
puts Seeder.report

Then run ‘rake db:seed’

Seeder will create two new things.

You’ll then be able to do this:

thing = Thing.find_by_name(:foo)
thing.colour    ---> 'red'

Outside Rails

Dibber can be used outside of Rails, but in this case you will need to specify the location of the seed files.

Seeder.seeds_path = "some/path/to/seeds"

You can also use this technique in Rails if you want to put your seed files in an alternative folder to ‘db/seeds’

Report

Seeder.report outputs a report detailing start and end time, and a log of how the number of things has changed

Overwriting existing entries

Seeder#build will not overwrite existing data unless directed to do so.

thing.update_attribute(:colour, 'black')
Seeder.seed :thing
thing.reload.colour  ----> 'black'

Seeder.seed(:thing, :overwrite => true).build
thing.reload.colour  ----> 'red'

Using alternative class and field name mappings

Seeder.seed calls Seeder#build to build the objects defined in the seed files. You can call the build method directly if your seed file names do not match the class name:

Seeder.new(Thing, 'other_things.yml').build

More examples

Take a look at test/examples/seeds.rb for some more usage examples.

If you clone this app, you can run this example at the project root:

ruby test/examples/seeds.rb

There is also an example of process log usage:

ruby test/examples/process_logs.rb