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gem install pg -v '0.18.1' -- --with-cflags="-Wno-error=implicit-function-declaration"

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#routes.rb
Rails.application.routes.draw do
  get 'fresh_updates', to: 'home#fresh_updates', constraints: { format: :xml }
end

#home_controller.rb
class HomeController < ApplicationController
  def fresh_updates
    updater = Updater.new
    updater.call # updates fresh_updates file

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# https://www.codewars.com/kata/52b7ed099cdc285c300001cd/train/ruby

require 'pry'

def sum_of_intervals(intervals)
  res = intervals
  del = []
  new_res = []
  stop = false

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require 'open-uri'

@files =
[
  'file_example_JPG_1MB.jpg',
  'file_example_GIF_1MB.gif',
  'file_example_PNG_1MB.png'
]

def sync

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Finding a Ruby memory leak using a time analysis

When developing a program in Ruby, you may sometimes encounter a memory leak. For a while now, Ruby has a facility to gather information about what objects are laying around: ObjectSpace.

There are several approaches one can take to debug a leak. This discusses a time-based approach, where a full memory dump is generated every, say, 5 minutes, during a time that the memory leak is showing up. Afterwards, one can look at all the objects, and find out which ones are staying around, causing the

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MacBook-Pro-Eugene:parimatch_rus-back j3ck$ ruby -v
ruby 2.3.5p376 (2017-09-14 revision 59905) [x86_64-darwin18]
MacBook-Pro-Eugene:back j3ck$ irb
2.3.5 :001 > order = []
 => []
2.3.5 :002 > columns = [
2.3.5 :003 >       {:name=>:id},
2.3.5 :004 >       {:name=>:em},
2.3.5 :005 >       {:name=>:na},
2.3.5 :006 >       {:name=>:si},

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При возникновении проблем с отображением кириллических символов можно попробовать 
отключить передачу переменных окружения LC* и LANG через ssh сессию. 
Для этого необходимо закомментировать SendEnv LANG LC_* в файле/etc/ssh/ssh_config.

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    def export
      favorites = Favorite.all
      @products = Product.where(id: favorites.map(&:product_id).uniq)

      count = favorites.group_by(&:product_id).map do |product_id, favorites|
        [@products.find { |product| product.id == product_id }, favorites.length]
      end

      @favorite_count = count.sort_by { |arr| arr.last }.reverse.to_h
    end

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host.docker.internal:port

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echo "%CPU   %MEM    MEM     PROCESS"
ps aux | awk '{mem[$11]+=int($6/1024)}; {cpuper[$11]+=$3};{memper[$11]+=$4}; END {for (i in mem) {print cpuper[i]"% ",memper[i]"% ",mem[i]" MB ",i}}' | sort -k3nr | head -n 5