ippeiukai’s gists

ippeiukai / sequel_each_in_batches.rb

Last active March 4, 2025 19:11

ActiveRecord's find_each and find_in_batches ported to Sequel. Sequel's paged_each is not practical when converting large data due to its use of transaction and offset. (Special thanks to @nomuson for working out the primary_keys_expr logic together.)

	# ActiveRecord's find_each and find_in_batches ported to Sequel.
	# Sequel's paged_each is not practical when converting large data due to its use of transaction and offset.
	#
	# Usage:
	#
	# SequelEachInBatches.find_each(dataset, keys) { \|record\| ... }
	#
	# It can also monkey patch Sequel::Dataset:
	#
	# Sequel::Dataset.send(:include, SequelEachInBatches)

ippeiukai / sequel_bulk_update.rb

Last active August 29, 2015 14:24

Bulk update some rows with different values. (for Sequel)

	module SequelBulkUpdate

	class << self

	# NOTE assumes the relation is simple
	#
	# @param relation [Sequel::Dataset] scope of update
	# @param values [Array<Hash{Symbol=>_},#to_h>] values of each row required for updating
	# @param where_columns [Array<Symbol>] columns used to identify the target row
	# @param set_columns [Array<Symbol>] columns to update

ippeiukai / active_record_relation_exitsts.rb

Last active August 29, 2015 14:27

A hack to make `where(relation.exists)` work in 4.2. See https://github.com/rails/rails/issues/16959 for details of the problem and proposed proper solution.

	module ActiveRecordRelationExists

	# DANGER this switches ActiveRecord::Relation#exists from delegation to arel to our implementation that returns a String with a twist.
	# This achieves the most common usage of #exists before 4.2. Proper fix will be: https://github.com/rails/rails/issues/16959
	def exists
	SqlStringWithNot.new("EXISTS (#{self.to_sql})")
	end

	class SqlStringWithNot < String

ippeiukai / enumerator_with_position_and_size.rb

Created August 27, 2015 02:14

Add `with_position_and_size` method to Enumerator. Those are quite handy inside a loop.

	module EnumeratorWithPositionAndSize

	# @yields [original_params, position_and_size]
	# @yieldparam position_and_size [(Integer, Integer)] 2-element array of position (first being 1) and size; size may be nil (see Enumerator#size)
	# @example
	# %w[a b c d e].each.with_position_and_size { \|char, (position, size)\| puts "#{char} (#{position}/#{size})" }
	def with_position_and_size
	return to_enum(__method__) unless block_given?
	my_size = self.size
	self.with_index(1) do \|original_params, position\|

ippeiukai / io_streaming_response_body.rb

Last active November 25, 2015 09:22

Stream data as a file in Rails as they are written to IO.

	class IOStreamingResponseBody

	def self.render(options = {}, &block)
	instance = new(options)
	instance.define_singleton_method :render do \|dummy_io\|
	block.call(dummy_io)
	end
	instance
	end

ippeiukai / delegated_module_function.rb

Created November 24, 2015 07:51

Module functions on steroid. This allows you to define a set of methods as public module methods and private instance methods while keeping private dependencies private.

	# module FooBar
	# extend DelegatedModuleFunction
	#
	# define_delegated_module_functions do
	#
	# def foo_bar
	# 'Foo' + bar
	# end
	#
	# private

ippeiukai / string_to_json_escape_outside_bmp.rb

Created December 8, 2015 06:14

monkey patch to ruby's JSON that escapes chars bigger than 3 bytes in UTF-8

	require 'active_support'
	require 'active_support/concern'
	require 'active_support/core_ext'
	require 'active_support/json'

	# String#to_json to escape any string outside BMP
	module StringToJsonWithEscape4byteUtf8
	extend ActiveSupport::Concern

	included do

ippeiukai / association_exists.rb

Created February 14, 2016 13:30

association_exists model plugin for Sequel. Like association_join, allows you to filter dataset with association.

	module Sequel
	module Plugins
	module AssociationExists

	module DatasetMethods

	def association_exists(association, &block)
	_association_exists(association, &block)
	end

ippeiukai / enumerable_product.rb

Created February 23, 2016 02:11

Monkey patch to provide Cartesian product of enumerables in ruby.

	module Enumerable

	def self.product(first, *rest)
	return enum_for(__method__, first, *rest) unless block_given?
	if rest.empty?
	first.each do \|v0\|
	yield [v0]
	end
	else
	enum_for_rest = product(*rest)

ippeiukai / config.rb

Created May 26, 2016 09:48

	module Rubinius
	config = {}
	config[:config_file] = "/Users/ippei/src/rubinius-3.33/config.rb"
	config[:command_line] = ["--prefix=/Users/ippei/.rvm/rubies/rbx-3.33", "--with-opt-dir=/usr/local/opt/openssl:/usr/local/opt/readline:/usr/local/opt/libyaml:/usr/local/opt/gdbm", "--llvm-path=/usr/local/Cellar/llvm/3.6.2"]
	config[:build_make] = "make"
	config[:build_rake] = "rake"
	config[:build_perl] = "perl"
	config[:llvm_path] = "/usr/local/Cellar/llvm/3.6.2"
	config[:llvm_system_name] = nil
	config[:llvm_configure] = "/usr/local/opt/llvm/bin/llvm-config"

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