[Ruby on Rails] ArgumentError (invalid byte sequence in US-ASCII)

Fixing `ArgumentError (invalid byte sequence in US-ASCII)` in Rails by adding `# encoding: utf-8` to the file header.

[MySQL] Getting stuck with reserved words - ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'xxx' at line 1

MySQL threw ERROR 1064 on a query because the column name primary is a reserved word.

[Node.js] Sanitize and validate with node-validator

A quick pointer to node-validator, a handy Node.js package for sanitizing and validating input.

[Ruby] Introduction to state_machine

Reference links for getting started with state_machine, a Ruby gem for managing object state transitions.

[Sublime Text 2] Customizing tab switching command with Ctrl+Tab

A small Sublime Text 2 keybinding tweak that switches `Ctrl+Tab` to walk tabs in order instead of by MRU.

[JavaScript][jQuery] Checking for the existence of DOM elements

Six ways to check DOM element existence in JavaScript and jQuery, ranked by execution speed.

[Facebook] Handling Revoked Permissions - 失効権限の取り扱い

A quick reference from Facebook's Handling Revoked Permissions doc on dealing with declined or revoked scopes.

[Ruby on Rails] How to change title for each page

Per-page title and meta tags in Rails using content_for and yield, with ERB and Haml examples.

[MongoDB] Display all records with find().forEach(printjson) or .toArray()

Two ways around mongo shell's 'has more' cutoff: .forEach(printjson) and .toArray().

[Chrome] Chrome extension 'jsoff' that can turn off JavaScript with one click

A quick pointer to 'jsoff', a Chrome extension for toggling JavaScript on and off with one click.

[Ruby] Use 'sunspot' for full-text search engine Solr

Reference links for the sunspot gem, which connects Rails apps to the Solr full-text search engine, including RSpec testing tips.

[Linux] About Memory Management

A quick reference note on Linux memory management and memory leak detection.

Image compression sites and tools summary

A short roundup of JPEGmini for JPEG, TinyPNG for PNG, and ImageOptim for the Mac.

JsDoc Toolkit Introduction

Intro notes on JsDoc Toolkit — reference sites, Homebrew install, and templates.

[WordPress] Steps to add a 'Send with LINE' button to WPTouch

Adding a 'Send with LINE' share button to WPTouch, and making it open in a new tab.

[Ruby] For file uploads, use 'CarrierWave'

Notes on the CarrierWave gem for file uploads in Rails, plus how to test uploads with RSpec.

[Ruby on Rails] How to limit default actions with 'only' while adding custom actions

Restrict Rails `resources` with `only:` and still add a custom collection action like `search`.

[Ruby on Rails] How to use acts_as_list

Reference links for using acts_as_list with jQuery UI Sortable in Rails.

[Ruby] Development HTTP Server 'Pow' by 37signals

Using 37signals' Pow — a zero-config Rack dev server for macOS — with Rails and Sinatra apps.

[Ruby on Rails] Converting line breaks to br tags

A custom Rails helper for converting line breaks to br tags, without the p tags that simple_format inserts.

Summary of Google Chrome Developer Tools Introduction Articles

A short link roundup of introductory articles for Google Chrome Developer Tools.

[Ruby on Rails] How to get the current URL (including parameters)

Getting the current URL with url_for(params) in Rails 3, plus adding and removing query parameters.

Haml Tips

Handy Haml tips: conditional class names and repeating ul/li output with in_groups_of.

[Capistrano] Recipe for executing rake tasks

A Capistrano recipe for invoking rake tasks on a remote server, with a namespace-collision workaround.

[Node.js] How to resolve Error: Cannot find module 'express'

Fixing Node.js Cannot find module 'express' by reinstalling dependencies with npm install -d.

[RSpec] Various ways to use Devise in test code

Rails + RSpec notes on testing Devise-protected controllers by stubbing current_user in a before block.

[Node.js] gyp ERR! configure error Error: EACCES, mkdir '/Users/name/.node-gyp'

Working around node-gyp's EACCES mkdir '/Users/name/.node-gyp' error with mkdir and chmod.

[Mac] Steps to install GMP with Homebrew

Install GMP, the arbitrary precision arithmetic library, on macOS with a single `brew install gmp`.

[Mac] Steps to install ImageMagick with Homebrew

A quick note on installing ImageMagick on macOS with a single Homebrew command.

[Mac] Installing MongoDB with Homebrew

Installing MongoDB with Homebrew on macOS and setting it up as a launchd auto-start service.

[Ruby on Rails] How to use helper methods in controllers and models

How to call Rails helper methods from controllers and models by including ActionView::Helpers.

[Ruby on Rails] How to use arel_table

Reference links for learning how to use Rails' arel_table.

[Ruby on Rails] Use blank? or present? instead of nil? to check model attributes

Use blank? or present? instead of nil? when checking Rails model attributes.

[Ruby] Differences between count, size, and length

A link roundup on the differences between count, size, and length in Ruby.

[Ruby] RSpec Beginner Articles Summary

A curated list of beginner references for RSpec, grouped by topic (views, requests, syntax, config).

[cURL] GET/POST/PUT/DELETE

A short memo on using cURL's -X option to send GET / POST / PUT / DELETE requests.

[PHP] How to Use Excel_Reviser

Reference links for working with the Excel_Reviser PHP library, which even supports PHP 4.

[SEO] Website Performance Measurement Service "WebPageTest"

A quick introduction to the WebPageTest website performance measurement service.

[PHP][APC] Warning: require_once(): Unable to allocate memory for pool.

Silencing the APC Unable to allocate memory for pool warning by setting apc.mmap_file_mask=/dev/zero.

[Windows] How to use 'Junction' - a symbolic link-like feature

A quick reference memo on using Junction on Windows 7 as a Linux-style symbolic link.

[JavaScript] How to Fix Sidebar Parts with jQuery When Scrolling

Link collection of reference articles for fixing a sidebar in place while scrolling with JavaScript or jQuery.

[RSpec] Differences between stub and mock

A link roundup of references that helped me get stubs vs. mocks straight in RSpec.

[Ruby on Rails] Overriding Devise's current_user method

Overriding Devise's current_user with alias_method to always include the user's Role.

[Ruby][FactoryGirl] Could not find a valid mapping for #<User

A record of running into the "Could not find a valid mapping for User" error with FactoryGirl and Devise.

[Ruby][RVM] mysql2.bundle: [BUG] Segmentation fault

Fixing a mysql2.bundle segmentation fault after recreating an RVM gemset by updating RVM to head.

[Rails][FactoryGirl] Error: Factory already registered: xxx

A short note on the "Factory already registered: xxx" error raised by FactoryGirl.

[Ruby] Convenient gem 'faker' for creating sample data

A short memo of reference links for 'faker', a Ruby gem that makes test and sample data generation easy.

[Ruby on Rails] How to create many-to-many relationship tables

Reference links for setting up many-to-many relationship tables in Ruby on Rails.

[Ruby on Rails] How to use seed-fu for easy seed data addition and management

Using the seed-fu gem to manage Rails seed data under `db/fixtures/`, with a CSV import example.

[Ruby] 'will_paginate' for adding pagination functionality

will_paginate helper options and localizing its labels through a locale YAML file.