Category: English

Categories
English PHP WordPress

HHVM and WordPress

Update 2014/4/17: This site now runs WordPress 3.9, which seems to be working fine with HHVM. Also, compatibility has improved, thanks to a patch in the WordPress core specifically for HHVM.

I recently posted about how I switched out PHP-FPM (PHP’s FastCGI pool) for HHVM. Today I’ll be talking more about the install process on the server, and using it to set up WordPress.

What is HHVM?

This is usually what happens in a (successful) startup[footnote]Twitter is (in)famous for its use of Ruby on Rails, which eventually had to be re-written in Scala, a language that runs on the JVM.[/footnote]:

  1. Initial codebase is written in an interpreted language, trading agility and developer productivity for slower response speeds and increased CPU usage on the servers.
  2. The service sees new users coming in and the initial codebase becomes strained.
  3. The service scales up the number of servers, but hits a wall.
  4. The codebase is re-written, either wholly or partially, in to a more performant and efficient language.

Facebook did steps 1 to 3, but refused to do step 4. Compiled languages, while having strengths in performance and efficiency, are usually harder to program in than interpreted languages. So, Facebook made something called HipHop for PHP. HipHop for PHP, or HPHPc for short, compiles PHP into C++, then compiles that into a big binary file. This allows PHP developers to do what they do best — develop in PHP, without worrying (too much) about performance.

As Facebook grew even more, HPHPc began to show its limitations[footnote]Compile time, compiled binary size, lack of MARKDOWN_HASH0f953f8e8cc058300e5041e6f079ab63MARKDOWN_HASH and MARKDOWN_HASH346e614b0b5901e8cdf0ca89b1b3950cMARKDOWN_HASH support, to name a few.[/footnote].

Out of this, came HHVM. HHVM is short for HipHop Virtual Machine, and uses a Just-in-Time (JIT) compiler to run PHP code. The main benefit developers do not need compile the whole binary every time they want deploy new code. With HHVM, Facebook has also worked towards full PHP 5.5[footnote]Wow HHVM is fast…too bad it doesn’t run my code[/footnote] support, support of create_function() and eval(), enabling the majority of PHP application frameworks to work with HHVM.

This includes…

WordPress

WordPress is written in PHP, and runs very well on HHVM. Previously, getting WordPress to work on HHVM required some patches to the core code[footnote]Getting WordPress running on HHVM « HipHop Virtual Machine[/footnote], but these issues have been resolved.

I’ve been running this blog on HHVM for about a week now, and response time is consistently 10x faster than before — 100x if using something like Batcache.

Installation

This server is running CentOS 6.3. While there are packages with HHVM pre-compiled, these packages are not officially supported by Facebook, and are usually compiled by individuals. Your mileage may vary, but package conflicts prevented me from installing any pre-compiled HHVM packages — so I had to compile it myself.

If you plan on running a server with HHVM from scratch, I highly recommend using Ubuntu, and the official precompiled packages for Ubuntu 13.10 / 12.04.

Bugs / Things to watch out for

Because HHVM is not PHP, you may occasionally run into unexpected behavior. Here are some problems I had while setting this site up:

  • No MySQLi support — this means tools like phpMyAdmin and database backup plugins that rely on MySQLi won’t work. Edit: HHVM 3.0 and above have MySQLi built in.
  • In the WordPress “General Settings” area, setting “Timezone” to something like “Asia/Tokyo” caused WordPress to crash. The “UTC +/- (hour)” settings seem to work fine.

That’s all, for now. When I run into more problems, I’ll make sure I post about them (with a workaround, if available).

Categories
English Tools

Japanese Input in Sublime Text

I really like Sublime Text. Today, I like it even more. Thanks to a blog post by Uesugi Shu, this long-open bug regarding Japanese character input has a viable workaround!

The link is in Japanese; I’ve (roughly) translated the steps required to achieve the same result below:

  1. Open the Sublime Text keymap file. This is at ~/Library/Application Support/Sublime Text 3/Packages/Default/Default (OSX).sublime-keymap — Sublime Text 3 didn’t let me edit the file in-place, so I had to use a different text editor.
  2. Find the following code blocks, and comment them out: 
    // Find panel key bindings
{ "keys": ["enter"], "command": "find_next", "context":
    [{"key": "panel", "operand": "find"}, {"key": "panel_has_focus"}]
},

    // Replace panel key bindings
{ "keys": ["enter"], "command": "find_next", "context":
    [{"key": "panel", "operand": "replace"}, {"key": "panel_has_focus"}]
},

    // Incremental find panel key bindings
{ "keys": ["enter"], "command": "hide_panel", "context":
    [{"key": "panel", "operand": "incremental_find"}, {"key": "panel_has_focus"}]
},
  3. (Optional) Comment out the following to fix kana-kanji conversion while typing regularly, as well: 
    { "keys": ["tab"], "command": "insert_best_completion", "args": {"default": "\t", "exact": true} },
{ "keys": ["tab"], "command": "insert_best_completion", "args": {"default": "\t", "exact": false},
    "context":
        [
            { "key": "setting.tab_completion", "operator": "equal", "operand": true }
        ]
},

  4. Re-open Sublime Text!

Categories
English Meta

Moved… Again!

So, I’m making some changes to this blog.

I’ll start with the first, which is most obvious. I’ve decided to change the theme I’ve been using for 2 years to Expound by Konstantin Kovshenin.

Second, which may (or may not) be so obvious. I’m running this site on NGINX (blog post), but I’ve switched out PHP-FPM for Facebook’s HHVM. Based on my preliminary benchmarks, response time is around twice as fast, and throughput has increased ten-fold. I will write a more comprehensive post about using HHVM in the near future.

The third is quite long, so bear with me:

I’ve been thinking recently, and in the first two to three years of blogging, I have started three blogs with more than three posts. This blog, which was previously hosted at http://keita.flagship.cc/, has always been my “main blog”. The idea of this blog from the start has been to make a repository of mistakes I’ve made, hopefully helping someone else who has run in to the same mistake later in time.

This core concept, will remain unchanged. I will continue to help people by writing about mistakes and problems I have made along the way. What I am changing, is the content on this blog.

Recently, I have become infatuated with the space-simulation game Kerbal Space Program. This infatuation has led to a re-kindling of my childhood desire to go to outer space — while I may never have the privilege to see our Earth from outside its atmosphere, I want to do whatever I can, to help the advancement of our civilization to a true space-faring civilization.

There are many hurdles humans face before this goal can be achieved, and we’re going to need as many people working on problems as we can manage. If just one person is motivated by reading about what I have to say on the issues that are preventing us from advancing as a civilization, I will be satisfied — the greatest obstacle we face may very well be ourselves.

Of course, I will still be writing about programming problems and solutions I encounter in my daily life and work — don’t worry!

Categories
English WordPress

wp_enqueue your scripts and styles.

The ease of making a WordPress theme is both a blessing and a curse. It allows people to get started with programming relatively easy — most hosting providers have PHP / MySQL, and the majority have a WordPress quick-install. However, this easiness comes with a dangerous pitfall — it’s easy to do the wrong thing. The classic example of this is query_posts (hint: never use it).

Today, I’ll talk about wp_enqueue_script and wp_enqueue_style. If you have ever made a plugin that requires additional stylesheets or scripts in the front-end, you know exactly what this is (and why it’s important).

The easy way out in this situation is to manually write scripts and styles in header.php like this:

...
<script src="<?php echo get_template_directory_uri(); ?>/hello.js"></script>
...
<?php wp_head(); ?>
...

Although this will work, you may start to notice funny things happening when you want to use jQuery.

...
<script src="<?php echo get_template_directory_uri(); ?>/hello.js"></script>
<script src="<?php echo get_template_directory_uri(); ?>/my_jquery.js"></script>
...
<?php wp_head(); ?>
...

The problem here is that WordPress actually uses jQuery internally for the admin bar. And, it doesn’t know that you’ve packaged your own version of jQuery — so it actually loads twice, when the admin bar is showing. This can cause problems that are time-consuming to fix, and just a waste of time.

WordPress has a mechanism to deal with this, wp_enqueue_script and wp_enqueue_style. These functions will determine the order of scripts and styles based on dependencies, and will only output the styles / scripts that are needed. This kills a few birds with one stone: loading everything in the correct order, making sure nothing is loaded twice, and not wasting bytes on scripts or styles that won’t be used by the current page.

Enough talk! Let’s get into the code.

First, you’ll need a functions.php, with the following code.

/**
 * Enqueue theme scripts and styles
 */
add_action( 'wp_enqueue_scripts', 'THEME_NAME_register_scripts' );
function THEME_NAME_register_scripts () {
  // wp_register_script( script identifier, absolute URI, array of dependencies, version )
  wp_register_script('home', get_template_directory_uri() . '/js/home.js', array('jquery'), filemtime(dirname(__FILE__) . '/js/home.js'));

  if (is_home()) {
    wp_enqueue_script('home');
  }
}

In this example, there is a JavaScript file called “home.js” in the “js” directory. This file requires jQuery, so it will be loaded after jQuery has finished loading. At the bottom of the function, the is_home() conditional is used to load the script only when the home page is showing.

Instead of using conditional tags in the wp_enqueue_scripts action, you can also register your scripts in the enqueue action, then enqueue them in the actual template file. Add the following to the template file, before get_header();:

add_action('wp_enqueue_scripts', function() { wp_enqueue_script('home'); }, 15);

This will load the ‘home’ script that we set up in the earlier snippet.

Have fun! I would be interested to hear feedback — any cool uses of wp_enqueue, et cetera.

Documentation

The syntax of wp_enqueue_style and wp_register_style is similar to the script counterparts, and they go in the same wp_enqueue_scripts action.

Documentation for wp_enqueue_style

Documentation for wp_register_script, including the scripts that WordPress has pre-packaged for you!

Documentation for wp_enqueue_script

Categories
English Uncategorized

Ruby 2.1.0-preview2

Ruby 2.1 is coming soon!

Personally, I’ve noticed quite a few speedups, and it seems like they’ve fixed a large memory problem I was running in to on pre-release staging environments:

fix memory consuming issue on RGenGC (r43532 and r43755)

I’d be interested in your experiences!

Categories
English Uncategorized

Git and Local / Server Hooks

I have been a proponent of pre-commit hooks for a very long time. After doing some searching, I found this lovely gem. It consists of a bunch of checks before you commit your code into the repository. A couple of my favorites:

  • php – Runs a PHP syntax check on all PHP files
  • merge_conflict – Makes sure you aren’t about to commit merge conflicts (you know, >>>>>>>> HEAD, stuff like that)
  • ruby_symbol_hashrockets – Prevents you from committing old-style Ruby hashes ( :hello => 'there' )

And much more. Highly recommended!

Categories
English Uncategorized WordPress

Turbolinks and WordPress

Rails Turbolinks is pretty cool, right? I thought it would be pretty cool to use it on WordPress, too.

There are probably a lot of bugs, and it probably doesn’t work well with JavaScript-heavy sites. I’ve included the jQuery compatibility layer, but it’s still not perfect. Use at your own risk.

To install, just search the WordPress plugin repository for “turbolinks”

wp-turbolinks

Or, available for download here:

http://wordpress.org/plugins/wp-turbolinks/

Contributors welcome!!!

Categories
English WordPress

WordPress 3.7: Automatic Updates

WordPress 3.7 Update Screen

WordPress 3.7 was just released.

Although there are quite a few features in this release, I want to talk about what I feel is the most important feature: automatic updates.

It’s a fairly simple – when a new version of WordPress is released, your installation will be updated (almost) immediately. As of 3.7, these automatic updates are limited to minor maintenance releases to make sure they won’t break your theme or plugin.

As WordPress has become more and more popular, exploits against WordPress have grown not just in quantity but also in complexity. As the threats have increased, so have the defenses — automatic security updates is just another step in the right direction. The last thing I want is for your blog / site to be compromised.

So, I strongly recommend updating to 3.7 as soon as existing themes and plugins have been verified to work with it (you’re using a staging environment… right?).

Happy updating!

Categories
Automate your Workflow English Uncategorized WordPress

Vagrant, WordPress, and Theme Development

I’ve been playing around with Vagrant recently. It really is a great tool for setting up development environments quickly and cleanly – no more local MySQL databases with 100 separate databases!

There are a few ways to solve this problem that many WordPress developers have:

  1. Use WordPress Multisite mode.
  2. Regularly clean your databases up and delete old ones.
  3. Use a common WordPress install, switching themes.
  4. Use Vagrant.

I’m going to be talking about the last option, Vagrant, in this blog post. I’ll list out a few reasons why Vagrant was attractive to me in the first place:

  • Isolation – this was appealing not only to reduce my database clutter, but also to be sure that the development and production environments were as similar as possible (within reason – of course).
  • Portability – another killer feature of Vagrant. Check out the repository, vagrant up, and you’re ready to go.
  • Coolness – don’t you love the idea of having contained, automatically managed environments for your projects? No? Well, I do.

Here’s what I came up with: vagrant-wp-theme-template.

It’s a template based on Underscores (_s), a template theme for WordPress themes. I’ve made two modifications: convert the CSS to SCSS, and the JavaScript to CoffeeScript. Grunt, an excellent automation tool, is used to compile the sources into CSS and JavaScript.

I’ve made the template compatible with _s, so just follow the instructions for _s regarding naming your theme, then the directions for getting your development environment set up. If you want to use an existing theme, just drop it inside the theme folder (and don’t forget to update the name in the Vagrantfile!)

I’m always open to new ideas and pull requests – please don’t hesitate to contribute!

Finally, this wouldn’t have been possible without the help of @miya0001‘s vagrant-chef-centos-wordpress, which this template is built off of. Thanks!

Categories
English Useful Utilities

Snoopy

Snoopy

Snoopy is a bookmarklet for snooping on web pages. It’s intended for use on mobile browsers (such as Mobile Safari on the iPad) where you can’t view-source to poke around under the hood of sites to see how they’re built. You might find it useful for your desktop browser, too.

This is very cool. I’ll need to put this onto my iOS test devices – it’s a lot faster than plugging in and using the remote debugger.