GroupsBy
Installation
Add this line to your application's Gemfile:
gem 'groups_by'And then execute:
$ bundle
Or install it yourself as:
$ gem install groups_by
Usage
There are several ways of using groups_by.
Base
The first way is to go through the GroupsBy class itself.
require 'groups_by'
# @param source [Array<Hash>]
# @option [Array<String,Symbol,Proc>] :group_by_rules
# @option [Proc] :summarizer
GroupsBy.new.groups_by(
source,
group_by_rules: grouping_rules,
summarizer: summarizer)CoreExt
The second way is to modify the Array class by including core extension.
require 'groups_by/core_ext/array' # extends only Array
data = [
{ value1: 10, value2: 100, name: 'Stanton', company: 'Smith Inc', id: '-one-' },
{ value1: 20, value2: 200, name: 'Stanton', company: 'Fisher LLC', id: '-three-' },
{ value1: 50, value2: 500, name: 'Darrel', company: 'Smith Inc', id: '-three-' }
]
result = data.groups_by(:name, :company, ->(el) { el[:id][/\w+/]})
# => {"Stanton"=>{"Smith Inc"=>{"one"=>[{:value1=>10, :value2=>100, :name=>"Stanton", :company=>"Smith Inc", :id=>"-one-"}]}, "Fisher LLC"=>{"three"=>[{:value1=>20, :value2=>200, :name=>"Stanton", :company=>"Fisher LLC", :id=>"-three-"}]}}, "Darrel"=>{"Smith Inc"=>{"three"=>[{:value1=>50, :value2=>500, :name=>"Darrel", :company=>"Smith Inc", :id=>"-three-"}]}}}
GroupsBy.pritify result
# =>
# Stanton
# Smith Inc
# one
# value1 value2 name company id
# 10 100 Stanton Smith Inc -one-
# Fisher LLC
# three
# value1 value2 name company id
# 20 200 Stanton Fisher LLC -three-
# Darrel
# Smith Inc
# three
# value1 value2 name company id
# 50 500 Darrel Smith Inc -three- Summarizer
You can pass summarize logic into grouper to summarize desirable values
data = [
{ value1: 10, value2: 100, name: 'Stanton', company: 'Smith Inc', id: '-one-' },
{ value1: 20, value2: 200, name: 'Stanton', company: 'Fisher LLC', id: '-three-' },
{ value1: 50, value2: 500, name: 'Darrel', company: 'Smith Inc', id: '-three-' }
]
grouping_rules = [:name, :company, ->(el) { el[:id][/\w+/]}]
summarizer = lambda do |elements|
{
value1_sum: elements.map { |m| m[:value1].to_f }.reduce(&:+),
value2_sum: elements.map { |m| m[:value2].to_f }.reduce(&:+)
}
end
result = GroupsBy.new.groups_by(
data,
group_by_rules: grouping_rules,
summarizer: summarizer)
# => {"Stanton"=>{"Smith Inc"=>{"one"=>{:values=>[{:value1=>10, :value2=>100, :name=>"Stanton", :company=>"Smith Inc", :id=>"-one-"}]}, :totals=>{:value1_sum=>10.0, :value2_sum=>100.0}}, "Fisher LLC"=>{"three"=>{:values=>[{:value1=>20, :value2=>200, :name=>"Stanton", :company=>"Fisher LLC", :id=>"-three-"}]}, :totals=>{:value1_sum=>20.0, :value2_sum=>200.0}}, :totals=>{:value1_sum=>30.0, :value2_sum=>300.0}}, "Darrel"=>{"Smith Inc"=>{"three"=>{:values=>[{:value1=>50, :value2=>500, :name=>"Darrel", :company=>"Smith Inc", :id=>"-three-"}]}, :totals=>{:value1_sum=>50.0, :value2_sum=>500.0}}, :totals=>{:value1_sum=>50.0, :value2_sum=>500.0}}, :totals=>{:value1_sum=>80.0, :value2_sum=>800.0}}
GroupsBy.pritify result
# =>
# Stanton
# Smith Inc
# one
# value1 value2 name company id
# 10 100 Stanton Smith Inc -one-
# value1_sum value2_sum
# 10.0 100.0
# Fisher LLC
# three
# value1 value2 name company id
# 20 200 Stanton Fisher LLC -three-
# value1_sum value2_sum
# 20.0 200.0
# value1_sum value2_sum
# 30.0 300.0
# Darrel
# Smith Inc
# three
# value1 value2 name company id
# 50 500 Darrel Smith Inc -three-
# value1_sum value2_sum
# 50.0 500.0
# value1_sum value2_sum
# 50.0 500.0
# value1_sum value2_sum
# 80.0 800.0 Pritify
Display grouped array in prettified way
Development
After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/karol-blaszczyk/groups_by. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
License
The gem is available as open source under the terms of the MIT License.
Code of Conduct
Everyone interacting in the GroupsBy project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.