bf4

# A script to migrate Sidekiq's redis to a new server.
# This obviously can work for any redis, but I only handled
# data types that Sidekiq uses.

require 'redis'

old_redis = Redis.new url: 'redis://old-redis:6379'
new_redis = Redis.new url: 'redis://new-redis:6379'

unknowns = []

bf4

on CI and local

export RUBYOPT="-W:deprecated" # show warnings, deprecations only

bf4

module AMS
  module V09
    class Serializer < ActiveModel::Serializer

       def serializable_hash(adapter_options = nil,
                             options = {},
                             adapter_instance = self.class.serialization_adapter_instance)
         object.nil? ? nil : super
       end
    end

bf4

#!/usr/bin/env ruby

require(Dir.pwd + "/config/environment")

ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
  ActiveRecord::Base.establish_connection(db_config.config)

  context = ActiveRecord::Base.connection.migration_context

  missing_migrations = []

bf4

List moved

Please use https://github.com/bf4/learning to fork and pull changes.

bf4

#!/usr/bin/env bash

git ls-files db/migrate/*.rb | sort | tail -1 | \
  ruby -e "schema_version=STDIN.read[/\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

require "active_record"

databases = ActiveRecord::Tasks::DatabaseTasks.setup_initial_database_yaml

db_namespace = namespace :db do
  if Rails.version.start_with?("6.0")

    # https://github.com/rails/rails/pull/38770/files
    namespace :rollback do
      ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |name|

bf4

  # Based on logfmt:
  # https://www.brandur.org/logfmt
  # For more complete implementation see:
  # see https://github.com/arachnid-cb/logfmtr/blob/master/lib/logfmtr/base.rb
  # For usage see:
  # https://blog.codeship.com/logfmt-a-log-format-thats-easy-to-read-and-write/
  # https://engineering.heroku.com/blogs/2014-09-05-hutils-explore-your-structured-data-logs/
  # For Ruby parser see:
  # https://github.com/cyberdelia/logfmt-ruby

bf4

Table of contents

• Concepts
• Reads
  • Basic Setup
  • Filtering
  • Custom Filtering
  • Sorting
• Custom Sorting

bf4

#!/usr/bin/env ruby

# List all keys stored in memcache. 
# Credit to Graham King at http://www.darkcoding.net/software/memcached-list-all-keys/ 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 = []