Using Serializers with ruby on rails

If you've ever wanted to want to have your data return specific kinds of data from different paths using Active Record with out having to write a lot of extra code serializers are the solution. They provide a way of reacting a custom json object.

This is what our data looks like now:

{
  "id": 1,
  "title": "Top Gun",
  "year": 1986,
  "length": 154,
  "summary": "As students at the United States Navy's elite fighter weapons school compete to be best in the class, one daring young pilot learns a few things from a civilian instructor that are not taught in the classroom.",
  "poster_url": "https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.imdb.com%2Ftitle%2Ftt0092099%2F&psig=AOvVaw0uR8BYBdnNmkTirteXeQzJ&ust=1674849371237000&source=images&cd=vfe&ved=0CA8QjRxqFwoTCIj9-Z6C5vwCFQAAAAAdAAAAABAE",  
  "created_at": "2022-05-21T13:12:35.682Z",
  "updated_at": "2022-05-21T19:11:11.682Z"
}

use the command below to have it installed in the gem file

gem 'active_model_serializers'

Once you run a bundle install then run:

rails g serializer model_name

it gets created in #app/serializers/model_name_serializer.rb

class ModelNameSerializer < ActiveModel::Serializer
  attributes :id, :title, :year, :length, :director, :description, :poster_url, :summary

end

after the serializer is created, it should now look like this:

{
  "id": 1,
  "title": "Top Gun",
  "year": 1986,
  "length": 154,
  "summary": "As students at the United States Navy's elite fighter weapons school compete to be best in the class, one daring young pilot learns a few things from a civilian instructor that are not taught in the classroom.",
  "poster_url": "https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.imdb.com%2Ftitle%2Ftt0092099%2F&psig=AOvVaw0uR8BYBdnNmkTirteXeQzJ&ust=1674849371237000&source=images&cd=vfe&ved=0CA8QjRxqFwoTCIj9-Z6C5vwCFQAAAAAdAAAAABAE"  
}

If you wanted to u wanted to create a custom method to return specific data based on what you have now, you could say:

def MovieCaption
  "#{self.object.title} - #{self.object.description}..."
end

and add that method to the attributes to return.

If you had an array of objects you have specify which serializer to use:

render json: movies, each_serializer: ModelNameSerializer, status: :ok

Something to be mindful is that serializers override when you want to specify what you return in the controller.

Here is a link to the Docs to read more on it.

api.rubyonrails.org

Thank you.