benoittgt

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

benoittgt

Specify a version before running commands

rvm use ruby-2.6
export RAILS_VERSION='~>6.0'
rm -f Gemfile.lock && bundle install --standalone binstubs
bundle exec rake smoke

To execute one cucumber test

benoittgt

# the script from the book was not working

import pcbnew

pcb = pcbnew.GetBoard()

for module in pcb.GetModules():
    print "ref: %s, pos: %s" %(module.GetReference(), module.GetPosition(),)

benoittgt

# From Juani Villarejo on Rails Speed Slack

class QueryReport
  PRETTY_PRINT = <<-PRETTY_PRINT_TEMPLATE.freeze
Total queries executed: %s 
Total execution time: %s

Queries executed
-----------------------
%s

benoittgt

# frozen_string_literal: true

RSpec::Matchers.define :have_data_count_of do |expected|
  match do |actual|
    if actual.is_a?(Hash)
      @json_api_payload = actual
    elsif actual.is_a?(String)
      @json_api_payload = JSON.parse(actual)
    else
      @invalid_payload_type_error = 'Please provide a Hash or JSON string'

benoittgt

require 'rspec/core/formatters/console_codes'
require 'rspec/core/formatters/documentation_formatter'

# Display "it" in RSpec doc format output
# $ rspec spec/foo/bar_spec.rb --format DocIt

class DocIt < RSpec::Core::Formatters::DocumentationFormatter
  RSpec::Core::Formatters.register self,
                                   :example_passed,
                                   :example_pending,

benoittgt

I have a custom https://github.com/rails/rails/blob/v5.2.1/activerecord/lib/active_record/associations/collection_association.rb#L278-L283 like this

      def add_to_target(record, skip_callbacks = false, &block)
        puts "#" * 60
        puts
        p association_scope
        p association_scope.class
        puts
        TracePoint.new(:call, :c_call){ |tp|

benoittgt

Big memory consumption when processing 4000 lines of CSV

Status

When processing thousands of CSV lines of user that need to be or not added to a group (and produce a very detailed report). We are seiing we huge increase in memory. Often the 2X Heroku dyno cannot manage it.

memory profiler

We use stackprof, memory_profiler. We look at tool like speedscope for stackprof results and always it point at heavy use of ActiveRecord. Also we notice in strings retained in memory_profiler report on string very present.

benoittgt

child_pid = spawn "psrecord #{Process.pid} --plot plot_#{Time.now.strftime('%H_%M_%S')}.png"

a = []
10_000_000.times { |i| a << i.to_s }

puts Process.kill('SIGINT', child_pid)
puts "continue scripting"

benoittgt

# frozen_string_literal: true
Rails.application.configure do
  config.lograge.enabled = true
  config.lograge.formatter = Lograge::Formatters::Logstash.new

  config.lograge.custom_options = lambda do |event|
    exceptions = %w[controller action format password]
    {
      uuid: event.payload[:uuid],
      host: event.payload[:host],