net-snmp Installation and Configuration Method

Installing net-snmp with yum and configuring snmpd.conf, service startup, and iptables port rules for Nagios monitoring.

[Apache] [warn] _default_ VirtualHost overlap on port 443, the first has precedence

The Apache 'VirtualHost overlap on port 443' warning was caused by duplicate entries across ssl.conf and proxy.conf.

[Apache] Invalid command 'SSLCertificateFile', perhaps misspelled or defined by a module not included in the server configuration

Resolving the SSLCertificateFile error on Apache by adding the mod_ssl module.

[Python] UnicodeDecodeError: 'ascii' codec can't decode byte 0xe3

Resolving a UnicodeDecodeError in a GAE Python handler by encoding the POSTed value to UTF-8.

How to Install Python 2.7.1 on CORESERVER

Installing Python 2.7.1 on CORESERVER and fixing python -V still showing 2.4.3.

[Sublime Text2] Installation Steps for Ubuntu

Installing Sublime Text 2 on Ubuntu — /usr/lib placement, sublime symlink, and a launcher .desktop entry.

[Ruby on Rails] Determine production/development Environment with Rails.env

Sample code notes for checking production/development environments with Rails.env in Ruby on Rails.

[Heroku][Rails] How to Install New Relic Add-on [Cedar Stack]

Installing the New Relic add-on into a Rails 3.2.5 app on Heroku's Cedar stack.

[Heroku] Solution for rake assets:precompile Error in Rails 3.2 Apps

Fixing the rake assets:precompile error on Heroku by tweaking application.rb in a Rails 3.2 app.

[Ruby on Rails] How to Configure Amazon SES (Simple Email Service)

Setting up Amazon SES over SMTP in Rails 3.2.5 with the aws-ses gem.

[SSH] Configuration to Backup Private Keys to Dropbox and Create Symbolic Links for Use

Backing up SSH private keys to Dropbox and using a symbolic link at ~/.ssh.

[Ruby on Rails] How to Apply Row Locking with ActiveRecord (Optimistic Lock, Pessimistic Lock)

Reference links for learning ActiveRecord's optimistic and pessimistic row locking.

[Heroku] How to Configure heroku-postgresql:dev

How to install the heroku-postgresql:dev add-on and promote it as the primary DATABASE_URL.

[Ruby on Rails] How to Display Error Messages for Devise Login Process

Adding alert output to Devise's sessions/new view to show login error messages.

[Facebook] Page Tab App (iframe) Redirect Problem and Solution

Why redirects from a Facebook Page Tab iframe blank the screen, and how `target="_top"` fixes it.

[Ruby on Rails] Created update_without_password! Method in Devise that Raises Exception on Save Failure

A record of adding an exception-raising update_without_password! method that Devise itself does not provide, defined on the User model.

[Heroku] How to Change WebServer from WEBrick to thin - [Rails 3.x on Heroku/Cedar]

Move a Rails 3.x app on Heroku Cedar off WEBrick and onto the more production-friendly thin server.

[Ruby][RVM] Installing Heroku in gemset global

Installing the heroku gem into the RVM gemset global so it's available from every gemset.

[RVM] How to Manage Ruby on Rails Versions

Managing Ruby on Rails versions with RVM by creating a dedicated gemset per Rails application.

[Excel] How to Paste Text Data (CSV Format)

A quick memo on how to paste CSV-formatted text data into Excel.

[Sublime Text 2] How to Configure Indent Settings

A memo on setting Sublime Text 2's Tab key to insert two spaces via tab_size and translate_tabs_to_spaces in Settings - User.

[Ruby on Rails] How to Specify Paths for Loading Images in JavaScript and CSS Files

How to reference images from JS/CSS under Rails' Asset Pipeline, using ThickBox as an example.

[jQuery] Usage and Reference Articles for "ThickBox" - Easy Dialog Display

Reference links for learning how to display dialogs easily with jQuery ThickBox.

[Sublime Text 2] How to Use Command Palette

How to open the Sublime Text 2 Command Palette with `Command + Shift + p` and filter to any command.

Sublime Text 2 Introduction, Settings, Customization Summary

A curated set of links for getting started with Sublime Text 2 — installation, Package Control, shortcuts, and useful packages.

[Ruby on Rails] How to Format Time and Set Initial Values in Input Forms

Notes on prefilling a form field with a strftime-formatted DateTime via text_field's value option.

Reference Articles for Haml Coding

A link roundup of Haml tutorials and cheat sheets I return to when I'm unsure about syntax.

[Ruby on Rails] How to Add Foreign Key Columns to Other Tables (add_column, references)

Adding foreign key columns in Rails migrations, for both new tables and existing ones.

[Ruby on Rails] Error: Range unspecified. Specify the :in, :within, :maximum, :minimum, or :is option.

The Range unspecified error from validates length was caused by a typo in minimum / maximum.

[Ruby on Rails] How to Implement Setters and Getters in ActiveRecord

Two ways to implement custom setters and getters on ActiveRecord models with define_method.

[Ruby on Rails] Permission Management and Authorization with "cancan" is Convenient

Reference links for introducing the cancan authorization gem into a Rails app.

[Lokka] How to Deploy and Run on Heroku

Steps to deploy the Ruby CMS Lokka on Heroku and use it as an English learning blog.

[Ruby on Rails] How to Set Basic Authentication for Non-Development Environments

Configuring Rails to apply Basic auth in production and staging while skipping it in development.

Collection of articles useful for learning Node.js

A list of Japanese-language articles that looked useful when I was learning Node.js.

[iPhone/iPad] "UDIDit" App to Check UDID → "UDID Sender" is Free

Since UDIDit went paid, use the free UDID Sender app to share your iPhone/iPad UDID.

Language Code Specification Memo

Reference links for the ISO 639 language code spec, handy when naming a DB column.

[Ruby on Rails] How to Change Default Values of Database Columns

Change a column's default value in Rails with change_column_default in a migration.

How to Add a Facebook App as a Tab on a Facebook Page

How to install a Facebook app as a Page tab using the /dialog/pagetab endpoint and its parameters.

[Eclipse] How to Display Dot Files "." Files (.htaccess etc.)

A short memo on making Eclipse Indigo show dot files like .htaccess in the Explorer view.

[Python] The Zen of Python

The original PEP 20 The Zen of Python side by side with a Japanese translation.

[Ruby][Rails] Curated Libraries and Tools Summary by WEB+DB PRESS Vol.67

A memo of curated Ruby/Rails libraries and tools by purpose from WEB+DB PRESS Vol.67.

[Ruby on Rails][SQLite3] SQLException: Cannot add a NOT NULL column with default value NULL

The cause of the SQLite3 NOT NULL column error in Rails migrations, and two ways to fix it.

[Coda] How to Set HAML/SASS Coloring (Syntax Highlighting)

Enable HAML and SASS syntax highlighting in the Coda editor by dropping mode files into the Coda Modes folder.

[Facebook] How to Configure The New Auth Dialog

Notes on configuring The New Auth Dialog for a Facebook App, with settings and dialog screenshots.

[Facebook] Received Warning Email "Notice of Violation: Privacy Policy"

The Facebook privacy policy violation warning email and how to fix it in the Auth Dialog settings.

[Ruby] How to Get Currently Logged-in User ID with User Authentication Engine "Devise"

Getting the currently logged-in user's ID from Devise via current_user.id.

[Haml] Solution for "syntax error, unexpected keyword_ensure, expecting keyword_end" Error

Fixing a Haml keyword_ensure syntax error caused by missing indentation inside an if branch.

[Git] Solution for "error: There was a problem with the editor 'vi'" Error

Fixing the git commit vi editor error by setting core.editor to your Vim path.

[Git] How to Set Files to Ignore in All Git Repositories Using Global .gitignore

How to configure `core.excludesfile` so a single `.gitignore` applies to every Git repository.

[Ruby on Rails] Reference Articles for User Authentication Engine "Devise"

Reference articles for introducing Devise into a Ruby on Rails application.