Let's say we have the following chart:

config/reports_kit/reports/my_posts.yml

measure: post
dimensions:
- created_at

In this YAML, measure: post tells ReportsKit to count the number of Post records, and dimensions: ['created_at'] tells it to group by the week of the created_at column. Since created_at is a datetime column, ReportsKit knows that it should group the counts by week (the granularity is configurable), sort them chronologically, and add in zeros for any missing weeks.

ReportsKit infers sensible defaults from your ActiveRecord model configurations. Since the Post model also has a belongs_to :author association, if you use dimensions: ['author'], then ReportsKit would count posts grouped by the author_id column and show author names on the x-axis.

If you need more customization (e.g. custom filters, custom dimensions, custom aggregation functions, custom orders, aggregations of aggregations, etc), ReportsKit is very flexible and powerful and supports all of these with a simple syntax. It lets you use SQL, too.

---

To create the chart above, simply add the following YAML file and call render_report in any view:

YAML

config/reports_kit/reports/how_it_works.yml

measure: post
dimensions:
- created_at

View

app/views/my_controller/my_view.html.haml

= render_report 'how_it_works'

Model

app/models/post.rb

class Post < ApplicationRecord
  belongs_to :author
  has_many :post_views, dependent: :destroy
  has_many :posts_tags, dependent: :destroy
  has_many :tags, through: :posts_tags

  include ReportsKit::Model
  reports_kit do
    aggregation :average_time_to_publish, [:average, 'posts.published_at - posts.created_at']
    contextual_filter :for_author, ->(relation, context_params) { relation.where(author_id: context_params[:author_id]) }
    dimension :approximate_views_count, group: 'ROUND(posts.views_count, -1)'
    filter :is_published, :boolean, conditions: ->(relation) { relation.where(status: 'published') }
  end

  STATUSES = %w(draft private published).freeze

  def to_s
    title
  end
end

Model's Columns

id              integer
author_id       integer
title           string
status          string
published_at    datetime
is_featured     boolean
views_count     integer
created_at      datetime
updated_at      datetime