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Code Snippets English

Retina

Been wondering how to simply retina-ize your website? Put this at the end of your site:

$(function() {
  try {
  if (window.matchMedia('(-webkit-min-device-pixel-ratio: 2), (min-device-pixel-ratio: 2)').matches) {
    $('.autoRetina').each(function(i, e) {
      var orig_src = $(e).attr('src');
      var new_src = orig_src.replace(/^(.*?).(png|jpe?g|gif)$/i, '$1@2x.$2');
      $(e).attr('src', new_src);
    });
  }
  } catch (e) {}
});

If you’re on a Retina-equipped device, your images with the autoRetina class will automatically be replaced with their Retina counterparts. If you’re familiar with iOS development, you’ll feel right at home. If you have no clue what I’m talking about, just append @2x at the end of the filename (before the extension).

If you want to apply it to all your images (do this only if you have Retina images for all of them!), replace $('.autoRetina').each( with $('img').each(

Caveat emptor: uses jQuery. Don’t judge.

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English Uncategorized

Varnish on a Dynamic Site

TL;DR: Scroll to the bottom for the attached VCL.

No, I’m not talking about the stuff you put on paint to make it last longer.

I’m talking about this amazing piece of software: https://www.varnish-cache.org/

Put simply, Varnish is a “reverse proxy” – a piece of software that goes between the main server and the client. Basically what it does is caches content, so PHP (or whatever backend you’re using) doesn’t need to run for every single request – this makes perfect sense with static content. For sites like WordPress, filled with mostly static content, Varnish will work out of the box (minor configuration changes are required for small things).

Using Varnish with mixed-static and dynamic content is a little harder, though. Recently, we were hired to optimize a client’s website. This particular website was written on a particularly horribly-written framework (it looked like some proprietary framework – not something I want to dissect and analyze for performance). For an example of how awful this framework was, it took about 10 seconds (yes, seconds) for the server to render the index page. After doing as much optimization as possible without dissecting, I was able to cut the time down to about 2 seconds.

2 seconds is still an eternity.

So, I decided to use Varnish. With a big caveat: it only caches content if you aren’t logged in. Since the framework I was working with was intent on setting the PHPSESSID cookie on every page load, I couldn’t just tell Varnish to cache when that cookie was present. Instead, when the user logs in, a LOGIN cookie is set, and Varnish uses this cookie to determine whether to cache the content or not. Logged-in users still have the awful user experience of having to wait 2 seconds for each page to load, but at least people who are just coming to look around have a decent experience.

Here are the relevant sections of the VCL file that enables this logic:

sub vcl_fetch {
  if (!(beresp.http.Set-Cookie ~ "LOGIN") && !(req.http.cookie ~ "LOGIN")) {
    unset beresp.http.Pragma;
    unset beresp.http.Set-Cookie;
    set beresp.http.Cache-Control = "public; max-age=1800";
    unset beresp.http.Expires;
    set beresp.ttl = 30m;
    return (deliver);
  }
}

sub vcl_recv {
  if (req.http.Cookie ~ "LOGIN") {
    set req.http.Cookie = ";" req.http.Cookie;
    set req.http.Cookie = regsuball(req.http.Cookie, "; +", ";");
    set req.http.Cookie = regsuball(req.http.Cookie, ";(PHPSESSID|LOGIN)=", "; 1=");
    set req.http.Cookie = regsuball(req.http.Cookie, ";[^ ][^;]*", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "^[; ]+|[; ]+$", "");
    if (req.http.Cookie == "") {
      remove req.http.Cookie;
    }
  } else {
    remove req.http.Cookie;
  }
}
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English Uncategorized

Flagship LLC

As many of you are aware, I have been working for about 6 months now, with 2 other people.

On July 4th, we are pleased to announce that we have officially become a company, Flagship LLC. We have some pretty cool projects lined up in the near future, I’ll be posting updates on our released projects (and maybe if you’re lucky, bits and pieces of unreleased projects) here!

Our goal as a company is multi-fold, but I feel that the most important facet of Flagship is to bring modern web development and standards to Japan. In a country where Japanese translations of English reference material is prominent, especially in technology, we strive to be the flagship of truly born-in-Japan material.

I’m looking forward to the great things we’ll be accomplishing together, and I’m even more excited to share our products with all of you!