Query nested model with multiple plucks - ruby-on-rails

Question

I was just wondering if the following is possible: I have model with nested associative models. I want to be able to render json: on current_user.reports.minned and have it eager_load the plucked values from each model. How can I accomplish this?
Here I use only 2 models as an example. In reality, the solution needs to work for n+1 nested models.
Does not work:
class Report
has_many :templates
def minned
self.pluck(:id, :title)
self.templates = templates.minned
end
end
class Template
belongs_to :report
def minned
self.pluck(:id, :name, :sections, :columns)
end
end
....
# reports.minned.limit(limit).offset(offset)
# This should return something like:
[{
'id': 0,
'title': 'Rep',
'templates': [{
'id': 0,
'name': 'Temp'
'sections': [],
'columns': []
}]
},
{
'id': 1,
'title': 'Rep 1',
'templates': [{
'id': 0,
'name': 'Temp',
'sections': [],
'columns': []
},
{
'id': 1,
'name': 'Temp 1',
'sections': [],
'columns': []
}]
}]
Thanks for any help.
Edit:
I will add that I found a way to do this by overriding as_json for each model, but this applies the plucking to all requests. I need to have control over which requests give what pieces of information.
# in Report model
def as_json(options={})
super(:id, :title).merge(templates: templates)
end
# in Template model
def as_json(options={})
super(:id, :name, :sections, :columns)
end
Thanks to eirikir, this is all I need to do:
Report model
def self.minned
includes(:templates).as_json(only: [:id, :title], include: {templates: {only: [:id, :name, :sections, :columns]}})
end
Then when using this with pagination order, limit or anything like that, just drop it at the end:
paginate pre_paginated_reports.count, max_per_page do |limit, offset|
render json: pre_paginated_reports.order(id: :desc).limit(limit).offset(offset).minned
end
Now I'm not overriding as_json and have complete control over the data I get back.

Answer 1

If I understand correctly, you should be able to achieve this specifying the output in the options given to as_json:
current_user.reports.includes(:templates).as_json(only: [:id, :title], include: {templates: {only: [:id, :name, :sections, :columns]}})