Book Review: RESS Essentials

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I have decided to start reviewing books as part of my blog activity with mixed emotions. Our industry is so fast moving, so ephemeral that books seem to fight a losing battle on being relevant the day they are published, never mind 6 months or a year down the road. Books on actual concrete products are very often little more than the missing manuals (so much so that O’Reilly actually has a ‘Missing Manuals‘ series, with a ‘The book that should have been in the box’ tagline – burn!). Just check the new titles – ‘Windows 8.1’, ‘HTML5’, ‘iPad’!!

Somewhat better fate is reserved for books that attempt to describe an approach or technique rather than any particular platform, language or library. Sound principles tend to outlive the actual building blocks used to implement them. The book I am covering in this review falls into that category, since it attempts to address a fairly new approach to wrestling with the explosion of Web clients.

The book’s title is ‘RESS Essentials’ by Joanna Krenz-Kurowska and Jerzy Kurowski and is brought to us by Packt Publishing. I already wrote about RESS in RESS to the Rescue. In a nutshell, responsive Web design (or RWD) is used to make a Web application adapt to the various aspects of the client, and reformat the experience to best fit each client in question (be it desktop, tablet or phone). RESS (or REsponsive design Server Side) goes further by involving the server. The rationale is that CSS can hide or reformat content depending on the client, but everything is still sent by the server, whether it will be needed or not. RESS attempts to address the performance side of the responsive design by choosing what to send before any formatting decisions are made on the client.

Even in Internet years, RESS is a young technique, and a very good illustration of that is that the authors felt the need to devote most of chapter 1 to controversies surrounding RESS. To put it simply, not everybody is convinced that RESS is a good idea. Nevertheless, enough people are (including the godfather of RESS Luke Wroblewski, incidentally another Pole – in a bit of Polish trivia, my photographer told me that his last name means ‘sparrow-like’). As such, the rest of the book assumes you have been sufficiently convinced RESS is a good and useful thing and you want to get on with it.

Chapter 1 also brought one of the unexpected insights into RESS and responsive design, where it can actually go to the other side of the client spectrum. When it comes to RWD, most of the focus is on how your site reacts to non-desktop clients. However, for eons the desktop design assumed certain maximum width and happily ignored the side bands, making browser window maximization futile. On high quality, large monitors these side bands seems like a waste of real estate (compared to how desktop applications or games use it). RESS and responsive Web design can unlock full potential of your high end monitor – no reason why we cannot add rules to keep adding more content if you maximize your browser on a 27” or 30” monitor.

In chapter 2, authors pay homage to the client side, by diving into the real world example using Gridpak for the responsive grid and Twitter’s Bootstrap for everything else.

Real action starts in chapter 3, where focus is moved to the server – the key value add of the RESS technique. In order to determine what to send to the client, server-side device detection is used. Two most popular solutions discussed in the chapter are WURFL and DeviceAtlas. There is a problem – these services are not available for free, or if they are, the free (or even cheap Cloud-based) version is not a viable option for anything but a test site. For completeness, authors cover some Open Source alternatives such as YABFDL (also known as Dave Olsen’s Detector) – more modest in its database but still usable and free with permissive license (with coverage that keeps up with new devices through the use of the modernizr.js library).

Chapter 4 puts server side detection into action. Different markups for different clients (to optimize for ability, support for modern features and JavaScript), different media sizes based on screen width, and manual selection of page versions. This chapter mostly deals with the first of the three goals, with plenty of code snippets using both WURFL and Dave Olsen’s Detector.

Chapter 5 moves on to dealing with image resolution on the server. Images comprise a large portion of the overall site payload and sending images that are too large or of unnecessarily high resolution is costly both performance-wise, but also by eating into the monthly bandwidth allowance for mobile users. The RESS solution for handling image sizes and resolution is in line with the overall approach and has some interesting properties compared to the known alternatives.

As said, all this effort around sending the right-sized images to the client is at least partially driven by performance considerations. In chapter 6, authors note that client screen size is not the only parameter to take into account – connection bandwidth is as important. Unfortunately, as of today there are no media queries for connection quality and bandwidth that could be used to tailor image size and compression to use. In their absence, authors offer a number of techniques to optimize images or reduce the need to use them in the first place.

One thing I really liked in this chapter was a graph showing that with the reduction of screen size (and with RESS solution for images enabled), the size of CSS and JavaScript files started to overtake images, to the point where images were only 1/3 of the CSS/JavaScript files for iPhone portrait resolutions (320px). This was a good reminder that RESS needs to be combined with other good practices if performance was a concern. I particularly liked a tidbit that the average webpage reached 1585 KB on September 15, 2013. That’s a lot of KBs to send to any client, particularly mobile phones, and underlines the need for techniques such as RESS to improve Web performance.

Changing gears, chapter 7 switched back to the client and focused on using and extending jQuery and Bootstrap to make your site responsive when dealing with elements such as tables and carousels. jQuery has essentially become the equivalent of gravity for JavaScript libraries (i.e. you cannot avoid it and must play nice with it), and Bootstrap is insanely popular in its third incarnation. While not necessarily limited to RESS (the code in this chapter could be easily used in a client-only RWD solution), we should not forget that RESS is a combination of server and client side techniques for responsive design, and the examples in this chapter are definitely useful for Web developers that seek responsive design solutions.

I am a bit puzzled with chapter 8, which introduces REST and combines it with RWD. It is not strictly RESS in that it simply uses Ajax to call REST services. There is nothing wrong with what is proposed in this chapter, but REST is another kind of ‘gravity’ for many teams including mine, and tossing it here on the pile with RESS and RWD seems odd, particularly because it involves PHP in code examples. Since this was the last chapter in the book, I was left wanting for a chapter that is more fit for wrapping it all up and reinforcing the key messages of the book (an epilogue, as it were).

In the end, where does it left me, the reader and the reviewer? I would say that RESS Essentials is part of the new breed of ‘mini-books’, considering its size (120 pages including index). It is definitely not the first of its kind – Responsive Web Design by Ethan Marcotte is 143 pages, and Mobile First by Luke Wroblewski is 123 pages. This class of books covers areas and topics that are too complex to be covered in one blog post or article but perhaps not as complex to require a book that can double as a weapon and will consume years of author’s life. The format definitely allows hot topics to be covered in a time frame that at least gives them a fighting chance of having some decent use before the inevitable progress renders them obsolete.

I think that the authors did a good job covering the ground on the topic of RESS and I definitely learned a lot by reading it. The book is part of the ‘Community Experience Distilled’ series, and it definitely fits the description, since the authors provided a number of examples and code snippets that look like something they arrived at through personal experience while working on real world projects. Whether RESS itself has a staying power is left to be seen. I am concerned about the limited choices when it comes to server side agent detection (at least in the Open Source world), so Dave Olsen’s Detector effort should be commended.

When it comes to code snippets, I was more interested in general concepts than the server side code examples because they were universally in PHP. There is nothing wrong with PHP but I would prefer examples in Java, or even better, in JavaScript using Node.js. Using Java or Node.js would work better with the final chapter about combining REST with RESS.

As far as the format and language is concerned, I have two minor nits to pick. While the book is generally well written, Joanna’s and Jerzy’s Polish background occasionally creeps into their sentence structure. Not being a native speaker myself, I cannot quite put my finger on why I was able to notice, I just felt that way as I was reading. Another mild nit is that the PDF version of the eBook results in too small a font, and when I tap to zoom in, the text is single-spaced, making it less than perfect for reading on iPads. On the flip side, single spacing made for faster vertical scrolling. YMMV if you use a different reader or format.

That’s it for my first review – next on the docket is Smashing Magazine Book #4 – now that’s a book you can use for self defense if need be!

© Dejan Glozic, 2014

RESS to the Rescue

It seems that every couple of years we feel a collective urge to give a technique a catchy acronym in order to speed up conversation about UI design. Last couple of years, we grew accustomed to throwing around the term Responsive Design casually, probably because it rolls off the tongue easier then “we need to make the UI, like, re-jiggle itself on each thingy”. Although I like saying ‘re-jiggle’. Re-swizzle is my close second.

As we were working on the tech preview of the Jazz Platform Home app, we naturally wanted it to behave on phones and tablets. And it did. The header in particular is a breathing, living thing, going through a number of metamorphoses until a desktop caterpillar turns into a mobile butterfly:


It all works very well, but a (butter)fly in the ointment is that we need to send the markup for both the caterpillar and the butterfly on each request. We do CSS media query transformations to make them do what we want, but we are clearly suboptimal here. I am sure that with some CSS shenanigans we could pull it off with one set of HTML tags, but at some point it just becomes too hard and error-prone. Clearly it is one thing to make the desktop/tablet header drop elements and adjust with screen size, and another to switch to a completely new element (off-screen navigation) while keeping the former rotting in the display:none hell.

This is not the only example where we had to use this technique. The next example has the section switcher in the Project Details page go from vertical set of tabs to a horizontal icon bar:


Again, both markups are sent to the client, and switched in and out by CSS as needed. This may seem minor but in a more complex page you may end up sending too much stuff on all clients. We need to involve the server into this using some kind of a hybrid technique.

As JJG before, Luke Wroblewski has not actually invented this technique but simply put a name on it. RESS stands for REsponsive design + Server Side and first appeared in Luke’s article in 2011. The technique calls for involving the server in responsive design so that only what is needed is sent to the client. It also goes by the name ‘adaptive design’. The server is not meant to replace but rather complement responsive design. You can view the server as a more coarse-grained player in this duo, sending ‘mobile’ or ‘desktop’ stuff to the client, while the responsive design takes care of adapting to the device in more steps or decision points. It needs to because what does it mean ‘mobile’ today anyway? There is a continuum of screen sizes now, from phones to phablets to mini-tablets to regular tables to small laptop screens to desktops – what is ‘mobile’ in that context?

It seems like RESS would help us in our two examples above by allowing us to not send the desktop header to the phone and off-screen navigation to the desktop. However, the server has limited means to perform device detection. At the very bottom, there is HTTP header ‘user-agent’. Agent sniffing is a never-ending task because of new devices that keep coming online. There is a lot of virtual ink spilled on the algorithms that will correctly detect what you are running. This is error-prone activity relying on pattern matching against lists that normally go stale if not updated constantly. There were attempts to subcontract this job, but many are either stack-specific or fee-based (such as WURFL or, or a combination of all these approaches. I don’t see how any of these solutions make sense to most of the web sites that want to go the RESS route. Simply judging by the number of available solutions, you can see that this is not a solved problem, analogous to the number of hair loss treatments.

Another approach we can use (or combine with user agent detection) is to send the viewport size to the server in a cookie. This arms the server with the additional means to make correct decision because while, say, iPad is reported as ‘mobile’, it has enough resolution to be sent a full desktop version of the page, and viewport size would reveal that. The problem with this technique is that your site needs to be visited at least once to give JavaScript a chance to set the cookie, which means that the optimization only kicks in on repeat visits.

Considering the imprecise nature of device detection, you should consider RESS a one-two approach – server tries its best to detect the device and send the appropriate content, then responsive design on the client kicks in. A prudent approach would be to err on the safe side on the server and give up on device detection at the first sign of trouble, letting the client do its thing (when, say, user-agent has never been seen before or cookies are disabled preventing viewport size transmission). With this approach, we should ensure that client-side responsive design works well on its own, and consider server-side an optimization, a bonus feature that kicks in for the most straightforward cases (i.e. most well known phones, tablets) and/or on repeat visits.

By using the vision analogy, the most you would expect your server to do in a RESS-enabled site is to tell you that the vehicle on the road is a car and not a truck, and that it is black(ish). As long as you don’t expect it to tell you that it is a 2012 BMW i3 with leather seats and technology package, you will be OK.

© Dejan Glozic, 2013