ippeiukai’s gists

ippeiukai / sequelize-find-each.js

Last active May 2, 2024 01:27

Sequelize port of find_each in ActiveRecord. (https://github.com/sequelize/sequelize/issues/686 )

	"use strict";

	const Sequelize = require('sequelize');
	const Promise = Sequelize.Promise;

	const DEFAULT_BATCH_SIZE = 3000;


	/**
	* Port of ActiveRecord::Base.find_each of Rails.

ippeiukai / singleton_with_class_delegator.rb

Created June 17, 2016 07:53

Singleton but as convenient as class methods; it's both.

	module SingletonWithClassDelegator
	extend ActiveSupport::Concern

	included do
	include Singleton
	original_delegate_method = method(:delegate).unbind if self.respond_to?(:delegate)
	extend SingleForwardable
	if original_delegate_method.present?
	# restore the delegate of ActiveSupport that has been overshadowed by SingleForwardable
	define_singleton_method :delegate, original_delegate_method

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 / 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 / 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 / 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 / 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 / use_single_forwardable_with_active_support.rb

Created May 14, 2015 02:29

Have you ever wanted to use def_single_delegator from SingleForwardable but still continue to use `delegate` of ActiveSupport?


	module UseSingleForwardableWithActiveSupport
	extend ActiveSupport::Concern

	included do
	original_delegate_method = method(:delegate).unbind if self.respond_to?(:delegate)
	extend SingleForwardable
	if original_delegate_method.present?
	# restore the delegate of ActiveSupport that has been overshadowed by SingleForwardable
	define_singleton_method :delegate, original_delegate_method

ippeiukai / mongoid_custom_array.rb

Last active November 25, 2015 09:27

A rough solution to https://jira.mongodb.org/browse/MONGOID-3042

	module MongoidEmbeddedObjectModification

	# Custom field behaves more like an immutable value.
	# Your changes to the object obtained with getter method will not take an effect unless you assign it back.
	# https://github.com/mongoid/mongoid/issues/3341
	def modify(mongoid_doc, field_name)
	obj = mongoid_doc.public_send(field_name)
	yield obj
	mongoid_doc.public_send("#{field_name}=", obj)
	end

ippeiukai / mongoid_embedded_object.rb

Last active August 29, 2015 14:08

A rough solution to https://github.com/mongoid/mongoid/issues/3794

	module MongoidEmbeddedObjectModification

	# Custom field behaves more like an immutable value.
	# Your changes to the object obtained with getter method will not take an effect unless you assign it back.
	# https://github.com/mongoid/mongoid/issues/3341
	def modify(mongoid_doc, field_name)
	obj = mongoid_doc.public_send(field_name)
	yield obj
	mongoid_doc.public_send("#{field_name}=", obj)
	end

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