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bf4 / db-switch.rb
Created Aug 30, 2021 — forked from matthewd/db-switch.rb
View db-switch.rb
#!/usr/bin/env ruby
require(Dir.pwd + "/config/environment")
ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
context = ActiveRecord::Base.connection.migration_context
missing_migrations = []
bf4 /
Last active Jul 17, 2021
Some Ruby Learning Resources
bf4 / bin-squash_migrations
Created Nov 12, 2015
Squash Rails migrations in this one easy step
View bin-squash_migrations
#!/usr/bin/env bash
git ls-files db/migrate/*.rb | sort | tail -1 | \
ruby -e "[/\d+/]; init_schema=%(db/migrate/#{schema_version}_init_schema.rb);
%x(git rm -f db/migrate/*.rb;
mkdir db/migrate;
git mv db/schema.rb #{init_schema};
rake db:migrate;
git add db/schema.rb; git commit -m 'Squashed migrations')"
bf4 / db.rake
Created Nov 2, 2020
Rails 6.0 multi-db extensions for migration tasks
View db.rake
require "active_record"
databases = ActiveRecord::Tasks::DatabaseTasks.setup_initial_database_yaml
db_namespace = namespace :db do
if Rails.version.start_with?("6.0")
namespace :rollback do
ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |name|
bf4 /
Last active Oct 22, 2020
a polymorphic many-to-many association in Rails

This was my solution for a polymorphic many-to-many association

class ItemCountry < ActiveRecord::Base
  belongs_to :locatable, :polymorphic => true
  belongs_to :country
  # fields are :locatable_id, :locatable_type, :country_id

class Title < ActiveRecord::Base
  has_many :countries, :through => :item_countries, :as => :locatable
View logfmt.rb
# Based on logfmt:
# For more complete implementation see:
# see
# For usage see:
# For Ruby parser see:
bf4 / Gemfile
Created Jul 2, 2013
Rails lograge and logstash request logging
View Gemfile
gem 'lograge' # more readable logs
gem 'logstash-event' # for logstash json format
gem 'mono_logger' # threadsafe logging
bf4 / dump_memcache.rb
Created Aug 2, 2019 — forked from BalmanRawat/dump_memcache.rb
Dumping and restoring the memcache key values using telnet & dalli gem
View dump_memcache.rb
#!/usr/bin/env ruby
# List all keys stored in memcache.
# Credit to Graham King at for the original article on how to get the data from memcache in the first place.
require 'net/telnet'
require 'csv'
headings = %w(id expires bytes key)
rows = []
bf4 / live_database_dump.rb
Last active Jun 19, 2019 — forked from njakobsen/live_database_dump.rb
Live stream a database dump (or any other STDOUT) using Rails 4. Why would you want this? If you have a large database dump and want to avoid storing it in memory as Rails streams it. This allows pipe the dump directly into the http response instead of storing it as a file, sending it, and then deleting it. Let me know what you think! I've teste…
View live_database_dump.rb
class DatabaseController < ApplicationController
def database_dump
database = Rails.configuration.database_configuration[Rails.env]["database"]
send_file_headers!(:type => 'application/octet-stream', :filename => "#{database}_#{}.backup")
pipe = IO.popen("pg_dump '#{database}' -F c")
stream =
while (line = # per
stream.write line
Thread.pass # per