A set of tools to tidy up rails seeds.rb files.
Dibber has two compoments:
Seeder is designed to simplify the process of pulling attributes from YAML files, and populating ActiveRecord objects with those attributes.
ProcessLog provides Seeder with a simple before and after reporting tool.
Add this to your Gemfile:
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 = :: 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'
Pass the name of the class to seed
All of these are equivalent commands
::. Thing ::. :thing ::. 'Thing'
Seed content can also have dynamic content added via ERB. For example, if you want the colour of the `foo` thing to be either 'red' or 'yellow', change `db/seeds/things.yml` to
foo: colour: <%= ['red', 'yellow'].sample %> size: large
Then when we run `Dibber::Seeder.seed :thing` a new `Thing` will be created with the colour set to either 'red' or 'yellow'.
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) 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:
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 a folder other than 'db/seeds'
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:
There is also an example of process log usage: