RESS
RWD and Server Side Components

Sven Wolfermann | maddesigns

Sven Wolfermann (36)

Sven Wolfermann - freelancer for moder web development

Freelancer for modern web development
(HTML5, CSS3, jQuery) from Berlin
CSS3 Adventskalender 2010/2011
wrotes articles and post for T3N-, PHP- and
Webstandards-Magazin (new: Screengui.de)
mobile Geek

Twitter: @maddesigns
Web: http://maddesigns.de

desktop vs. mobile

dividing pages

large site (feature rich) vs. small size (performant)

desktop vs tablet vs mobile

dividing more pages?

large site vs. tablet vs. small size

vs. car vs. fridge vs. watch vs. …

Responsive Web Design

Flexible grids, based on percentage units
Variable image and video sizes – images fit into grid
CSS3 media queries

image source: http://macrojuice.com/

RWD

solves many things

one URL, one code base, one deployment
all contents available (if not hidden)
Future friendly

moto.oakley.com

85.4MB page weight
471 HTTP requests
2 minutes 45 seconds until loading screen replaced with content
4 minutes 10 seconds until onLoad event

85.4MB, 471 HTTP requests!

THIS IS NOT RWD!

Oakley's monster page of baubles

moto.oakley.com fail

ok, ok, Oakley does it better now:
JUST 14.2MB, 291 request (more than 70MB less)

with mobile user-agent? 6.7MB, 114 requests :/

Oakley's Moto diet

RWD

has some issues

site tend to be too large for mobile
some content is hard to adapt: images, tables, ads, ...
IE8 doesn't understand RWD (basically)

Guy Podjarny's RWD performance tests

sites have nearly same weight on mobile as on desktop

Real World RWD Performance – Take 2

Performance

Reduce image payload (the biggest effect)
Reduce JavaScript and CSS payload
Further optimize based on feature detection

Lightening Your Responsive Website Design With RESS

Testing browser features with Vanilla JS

Cutting the mustard

if('querySelector' in document
  && 'localStorage' in window
  && 'addEventListener' in window) {
    // bootstrap the javascript application
  }

if browser supports
'querySelector',
'localStorage'
and 'addEventListener'
do hot stuff

BBC Responsive News – Cutting the mustard

Modernizr

Client side feature detection

Modernizr is a JavaScript library that detects HTML5 & CSS3 features in the user's browser.

http://modernizr.com/

Modernizr

throw in <head>

<head>
  <script src="modernizr.js"></script>
</head>

Modernizr features test: geolocation

Modernizr.geolocation // true or false

if (Modernizr.geolocation) {
  navigator.geolocation.getCurrentPosition(show_map);
} else {
  // no native support; maybe try a fallback?
}

Modernizr

Modernizr can load different files based on tests

Modernizr.load({
  test: Modernizr.geolocation,
  yep : 'geo.js',
  nope: 'geo-polyfill.js'
});

Modernizr.load is not part of the "development" version

Modernizr adds classes to <html>

<html class="js flexbox canvas canvastext webgl no-touch geolocation 
postmessage hashchange history boxshadow cssanimations csscolumns 
cssgradients csstransforms csstransforms3d csstransitions fontface 
video audio localstorage svg inlinesvg">

Modernizr

Another Sample: datepicker

<script src="modernizr.js"></script>

<script>
Modernizr.load({
  test: Modernizr.inputtypes.date,
  nope: ['jquery.datepicker.js', 'jquery.datepicker.css'],
  complete: function () {
    $('input[type=date]').datepicker({
      dateFormat: 'yy-mm-dd'
    }); 
  }
});
</script>

load jQuery datepicker library for browsers that don't have native datepickers

Conditional loading – window.matchMedia

Returns a new MediaQueryList object representing the parsed results of the specified media query string.

if (window.matchMedia("(min-width: 40em)").matches) {
  /* load secondary stuff */
}

matchMedia Polyfill

Modernizr.load and Picturefill uses matchMedia for example

MDN Window.matchMedia

Conditional loading – Modernizr.load

Modernizr loads scripts and CSS based on media queries

Modernizr.load([ 
  {
    test: Modernizr.mq("only screen and (min-width: 1051px)"),
    yep: '/js/large.js'
  },
  {
    test: Modernizr.mq("only screen and (min-width: 600px) and (max-width: 1050px)"),
    yep: '/js/medium.js'
  },
  {
    test: Modernizr.mq("only screen and (min-width: 320px) and (max-width: 599px)"),
    yep: '/js/small.js'
  }
]);

you can use EM in media queries too ;)

Conditional loading – pairing CSS & JS

holding CSS and JavaScript Breakpoints in sync

body:after {
  content: 'small';
  display: none;
}
@media (min-width: 650px) {
  body:after {
    content: 'middle';
  }
}
@media (min-width: 1200px) {
  body:after {
    content: 'large';
  }
}

Conditional loading – pairing CSS & JS

holding CSS and JavaScript Breakpoints in sync

var size = window.getComputedStyle(document.body,':after')
                 .getPropertyValue('content');

if (size == 'large') {
    // Load some more content.
}

Conditional CSS

Conditional loading – Ajax-include pattern

Replace:

<a href="..." data-replace="latest/fragment">Latest Articles</a>

Before:

<a href="..." data-before="latest/fragment">Latest Articles</a>

After:

<a href="..." data-after="latest/fragment">Latest Articles</a>

init with jQuery:

$("[data-replace],[data-before],[data-after]").ajaxInclude();

An Ajax-Include Pattern for Modular Content

Browser-Sniffing

remember the old days? Not? You lucky guy!
UA-string history

Browser-Sniffing

is hard and unreliable

For example, Safari user agent string on an iOS7 iPhone:

Mozilla/5.0 (iPhone; CPU iPhone OS 7_0 like Mac OS X) 
AppleWebKit/546.10 (KHTML, like Gecko) Version/6.0 Mobile/7E18WD 
Safari/8536.25

often browsers aims other browsers

detecting the "right" user agent is complicated

Parsing UA string is not a regex job

UA-Detection libraries

What?! UA-Sniffing is wild guessing

This is NOT a "mobile" detection!

if((navigator.userAgent.match(/iPhone/i)) || 
   (navigator.userAgent.match(/iPod/i))) {
   if (document.cookie.indexOf("mobile_redirect=false") == -1) {
     window.location = "http://m.yoursite.com/";
  }
}

Device Detection Libraries

WURFL (Java/.NET/PHP) free ^*
Scientiamobile (Java/.NET/PHP) commercial ^*
Device Atlas (Java/.NET/PHP) commercial
Netbiscuits' Device Library commercial
51degrees (.NET, C, Java, PHP) free limited / commercial
Open DDR (Java/.net) Open Source
Mobile Detect (PHP) Open Source

^* free with restricted license

Device Detection Libraries

Problems

updates are slow
not reliable

Client meets Server

set browser width cookie with JS

RESS = {};
 
RESS.writeCookie = function (name, value) { //cookie code }
 
//Store width in a cookie
RESS.storeSizes = function () {
    //Get screen width
    var width = window.innerWidth;
 
    // Set a cookie with the client side capabilities.
    RESS.writeCookie("RESS", "width." + width);
}
 
RESS.storeSizes();

Client meets Server

use cookie info in code

Setting a file path based on window.innerWidth

<?php 
  // grab the cookie value 
  $screenWidth = $_COOKIE['RESS']; 
  // set the img path var 
  if ($screenWidth <= 320) { 
    $imgPath = "320"; 
  } else if ($screenWidth < 960) { 
    $imgPath = "640"; 
  } else { 
    $imgPath = "960"; 
  } 
  // print out our image link 
  print "<img src='/rwd/images/".$imgPath."/car.jpg' alt='Car' />";
?>

http://www.netmagazine.com/tutorials/getting-started-ress

Client meets Server

use cookie info in code

<?php
  if ($RESS["width"] >= 320 && $RESS["width"] <= 640) {
?>
  <div class="mobile-ad max-320">
    <?php include "/ads/320.php"?>
  </div>
<?php } ?>

Modernizr Server

Client features for the server

<?php
    include('modernizr-server.php');
    print 'The server knows:';
    foreach($modernizr as $feature=>$value) {
        print "
 $feature: "; print_r($value);
    }
?>

The server knows:
canvas: 1
geolocation: 1
crosswindowmessaging: 1
indexeddb: 0
hashchange: 1
...

https://github.com/jamesgpearce/modernizr-server

RESS
Responsive Web Design + Server Side Components

In a nutshell, RESS combines adaptive layouts with server side component (not full page) optimization. So a single set of page templates deﬁne an entire Web site for all devices but key components within that site have device-class speciﬁc implementations that are rendered server side.

Luke Wroblewski @lukew

http://www.lukew.com/ff/entry.asp?1392

Advantages of RESS

Easier to navigate: The navigation structure can be customized for the different tasks.
Less page bloat: Instead of relying on display: none; or visibility: hidden; to hide page elements for mobile devices, removed from the HTML or CSS.
Faster load time: Unnecessary CSS/JavaScript can be removed from the HTML

Disadvantages of RESS

More server resources: Dynamically building the HTML will increase the load on the server.
Caching: A need for a better caching mechanism
Requires device detection: Mobile users will need to be detected. Device detection is unreliable.

RESS in the wild? -> Adaptive Images

http://adaptive-images.com/

Adaptive Images

Add .htaccess and adaptive-images.php to your document-root folder.
Add one line of JavaScript into the <head> of your site.
Add your CSS Media Query values into $resolutions in the PHP file.

Adaptive Images

The HTML starts to load in the browser and a snippet of JS in the <head> writes a session cookie, storing the visitor's screen size in pixels.
The browser then encounters an <img> tag and sends a request to the server for that image. It also sends the cookie, because that’s how browsers work.
Apache receives the request for the image and immediately has a look in the website's .htaccess file, to see if there are any special instructions for serving files.
There are! The .htaccess says "Dear server, any request you get for a JPG, GIF, or PNG file please send to the adaptive-images.php file instead."

Adaptive Images

The PHP file looks for a cookie and finds that the user has a maximum screen size of 480px.
It compares the cookie value with all $resolution sizes that were configured, and decides which matches best. In this case, an image maxing out at 480px wide.
It then has a look inside the /ai-cache/480/ folder to see if a rescaled image already exists.
We'll pretend it doesn’t - the PHP then goes to the actual requested URI to find the original file.
It checks the image width. If that's smaller than the user's screen width it sends the image.
If it's larger, the PHP creates a down-scaled copy and saves that into the /ai-cache/480/ folder ready for the next time it's needed, and sends it to the user.

http://adaptive-images.com/

Responsive Images
a topic for itself…

Responsive Images [german]

Detector (PHP RESS library)

combines UA-parsing and feature testing

includes User Agent parser – record any useful information (like OS or device name)
includes Modernizr Server

no need for commercial device detection libraries

add your own feature tests and store the results using Modernizr's addTest() API

Detector

HTTP request hits server
Detector compares User-Agent with database
if known, classify device and get back content
if not, Modernizr makes feature detection, stores cookie
reloads site, gives back specified content
stores UA-String/features combination for later use

How Detector works

Detector device families

The default install of Detector will categorize browsers into one of three families.

// families.json
{
    "tablet": {
         "isTablet": true
    },
    "mobile-advanced": { 
         "isMobile": true,
         "features": ["cssanimations","localstorage","deviceorientation"]
    },
    "mobile-basic": { 
         "isMobile": true
    },
    "desktop": {
         "isComputer": true
    }
}

Detector sample

switch ads, basic sample

if ($ua->family == 'mobile-basic') {
  include "/ads/simple.php";
} elseif ($ua->family == 'mobile-advanced') {
  include "/ads/responsive-ads.php";
} else {
  include "/ads/desktop.php";
}

Detector video sample

if ($ua->video->h264 || $ua->video->webm) {
      print $html5Embed; // YouTube's <iframe> code
} else {
      print $simpleLink;
}

RESS isn't the holy grail (RWD isn't either)

Client Hints

Client Hints is a new proposal by Ilja Grigorik and will allow clients to indicate a list of device and agent specific preferences. Spec Draft

(request)
GET /img.jpg HTTP/1.1
User-Agent: Awesome Browser
Accept: image/webp, image/jpg
CH: dpr=2.0

(response)
HTTP/1.1 200 OK
Server: Awesome Server
Content-Type: image/jpg
Content-Length: 124523
Vary: CH

(image data)

Automating DPR switching with Client-Hints

Client Hints

For example, given the following request header:

CH: dh=598, dw=384, dpr=2.0

The server knows that the client's screen height is 598px, width is 384px, as measured by density independent pixels on the device, and that the device pixel ratio is 2.0.

Client Hints

ReSrc.it can handle client hints now

Questions?

Thanks for your attention!

HTML5 slideshow by Google

Sven Wolfermann | maddesigns

http://maddesigns.de/RESS/

RESS RWD and Server Side Components

Sven Wolfermann (36)

www vs. m. desktop vs mobile

desktop vs. mobile

desktop vs tablet vs mobile

Responsive Web Design

A List Apart is responsive too now

Responsive Web Design

RWD

moto.oakley.com

85.4MB, 471 HTTP requests! THIS IS NOT RWD!

moto.oakley.com fail

RWD

Guy Podjarny's RWD performance tests

RWD is more

Performance

Browser Feature Detection

Testing browser features with Vanilla JS

Modernizr

Modernizr

Modernizr

Modernizr adds classes to <html>

Modernizr

Conditional loading

Conditional loading

Conditional loading

Conditional loading – window.matchMedia

Conditional loading – Modernizr.load

Conditional loading – pairing CSS & JS

Conditional loading – pairing CSS & JS

Conditional loading – Ajax-include pattern

Browser-Sniffing

Browser-Sniffing

Browser-Sniffing

What?! UA-Sniffing is wild guessing

This is NOT a "mobile" detection!

Device Detection

Device Detection Libraries

Device Detection Libraries

Client meets server

Client meets Server

Client meets Server

Client meets Server

Modernizr Server

RESS Responsive Web Design + Server Side Components

RESS

Sapient Nitro about RESS

Advantages of RESS

Disadvantages of RESS

RESS in the wild? -> Adaptive Images

Adaptive Images

Adaptive Images

Adaptive Images

Adaptive Images

Responsive Images a topic for itself…

Detector

Detector (PHP RESS library)

Detector

Detector device families

Detector sample

Detector video sample

RESS examples

RESS isn't the holy grail (RWD isn't either)

RESS – further reading

One more thing!

Client Hints

Client Hints

Client Hints

Questions?

Thanks for your attention!

RESS
RWD and Server Side Components

www vs. m.
desktop vs mobile

85.4MB, 471 HTTP requests!

THIS IS NOT RWD!

RESS
Responsive Web Design + Server Side Components

Responsive Images
a topic for itself…