Archive for the 'Design' Category

Should web developers also design?

Thursday, March 5th, 2009

A couple of months ago, The Pragmatic Programmers announced a new book. Web Design for Developers is described as,

how to make your web-based application look professionally designed. We’ll help you learn how to pick the right colors and fonts, avoid costly interface and accessibility mistakes—your application will really come alive. We’ll also walk you through some common Photoshop and CSS techniques and work through a web site redesign, taking a new design from concept all the way to implementation.

My question is this. Should a developer be trusted with design? It is definitely a profitable skill to have. I believe that developers should at least have a basic idea of what goes into design. I also believe that designers should have a basic understanding of web development. However, if someone is at one end of the spectrum or the other, how do they acquire the necessary skills?

There are several books written for each audience, but very few that are targeted at both. To my knowledge, this is the first book attempting to make a developer more capable as a designer. It appears to approach design in much the way a “logically driven”, coding brain works. It breaks down the fundamental components of design. Layout, color theory, spacing, mockups, etc. All are laid out with a logical process. In some ways it only scratches the surface. Entire books are written on color theory, or typography alone.
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So what’s for lunch?

Tuesday, February 26th, 2008

A couple of months ago, when ruby on rails 2.0 came out, I started a project to see if things had really changed all that much. I wanted something that was easy, but useful to me. At work, we had been discussing the pressing need for an easy to use listing of lunch places around our area. So, I decided, not only would I pick up rails 2.0, but I would see how hard it was to do a google maps mashup. Well, after a few days, I had the basics of a site up and running. Then of course, work got busy busy. (Something about launching our new website at work.) Well, in order to start benefiting from at least some of my effort, I spent the last weekend getting everything set up to deploy to my server, so without further ado, I present Lunchspot! Now, I wouldn’t call this a completed effort. In fact, it is only a faint echo of what I had hoped to have going by this time.

So why release it now? Well, because it is still quite useful. You can already submit your favorite lunch spots, comment on them, and see where they are on the map. Soon, I’ll have directions, ratings, sample menus, and “send to a friend” links. But the biggest reason to put it up, and then post about it, is to remind me to work on it, and solicit any help on things like design/layout and graphics (two of my weak areas).

So what is for lunch anyway?

Functional Invasion

Sunday, December 2nd, 2007

If you write software, or even pretend to write software, you have probably heard of functional programming. You may even know what functional programming is. If you do, then bear with me for a moment while I summarize things for those that don’t.

Languages tend to fall into one of three different paradigms. Procedural (c, perl, php, javascript), Object Oriented (c++, java, ruby), and Functional (haskell, ml, erlang). Now, this isn’t to say that a language only follows one specific paradigm. One can take java or c++ and implement code in all three paradigms. Same with almost any other language, but there tends to be a general layout to a language that makes it more suitable to one paradigm or another. So what are these paradigms?

Procedural – This is where you are effectively writing, step by step, what you want your application to do. You rarely have any abstraction, and your code tends to be fairly straightforward. Since everything is explicit, it can be optimized, and run very tightly. However, the responsibility is on you as the developer to make it so. You could just as easily (perhaps more easily) make your code brittle, bug ridden, and slow.

Object Oriented – This is where you have your code logically broken up into areas of responsibility. An object is a component of data, accompanied by the various bits of functionality that can act upon it. This paradigm tends to result in isolated functionality that is reused as the data is reused. This will typically lead to more maintainable projects with flexible abstractions allowing for minimal code doing maximal work. On the other hand, abstraction can be computationally expensive, and result in “magical functionality” that is very difficult to trace through. Again, it requires a responsible developer.

Functional – This is where you are concentrating on functions (in a mathematical sense) or algorithms. You build your program as a series of “data pipelines” that will take a given input and provide a desired output. These functions are written such that if the inputs remain the same, any number of calls to the function will always result in the same output. This paradigm, when properly followed, can allow for a compiler to make certain assumptions about the program being compiled, and can lead to some very radical optimizations. It also tends to discourage some of the more evil behaviors of programmers (such as modifying global data, having one function do many unrelated things, etc). The cost is that it requires a very different mindset when writing your programs. It can also be very tedious to write functionally styled code in a “non-functional” language.

The interesting thing about Procedural vs. Object Oriented paradigms is that they are still related. Inside the functions of an object, procedural code is used to do work. All you are really doing is introducing some forms of organization to the code layout. When you look at Procedural vs. Functional paradigms, you will find they are fundamentally different. Procedural code will lay out, step by step, what data you are using, and what you want to do to that data. In a functional language, this is not really the case. Instead, you will lay out what you want to do, and build compositions of functions to tie into each other. Then you will add inputs to the head of the function. Another way of thinking of this would be like using the pipe (‘|’) in the *nix Bash shell. Given data from some program, you want to transform it using other programs (like grep, awk, or sed) and then capture the results. Each of those utilities are like a function. Given the same inputs, they will always generate the same output. Piping the outputs of one function to the inputs of another is more or less the premise of functional programming.

So, if functional programming is so different than what everyone is used to, why does it matter? Well, it turns out that functions written in this way are typically easier to test. Since each function has no side effects, unit testing can be used effectively. Once a set of functions are well tested, then large majority of errors will be in the composition of functions, and these are easy for a compiler to catch in any relatively type safe language. Reuse can be maximized, resulting in a smaller, better tested, more maintainable code base. If you are using a functional language, then the compiler can do some very interesting things for optimization, and parallelization. Even if you are not using a functional language, many benefits can be had. The STL uses functional programming techniques extensively to allow c++ developers to enjoy some of the benefits. Still, to maximize the enjoyment of functional programming, one must use a functional language. Only then will the compiler leverage the assumptions that can be made about your code. It can, for example see that you always call a certain function with the same parameters every time, and replace that function call with the result directly. It can use cues that you provide to detect that a certain function can be run in parallel and automatically tie a thread-pool to the function.

So if you have looked at any of the functional languages and scoffed at the learning curve. Perhaps consider taking a second look. In fact, sometimes you will find the learning curve to be pretty reasonable. I recently ran across the book Programming Erlang: Software for a Concurrent Worldamazon.com. Once again the Pragmatic Programmers have worked to produce a book that makes learning fun and interesting. The learning curve is manageable, and the examples in the book are more than just trivial exercises. Erlang is an interesting language that makes working in a concurrent environment trivially simple, and on todays multi-core processors, that is becoming important. It can also pave the way to understanding more involved languages like Haskell. It can perhaps even allow you to understand the techniques of functional programming better so you can employ them in your non-functional language more effectively. After all, isn’t being more effective what this is all about?

-Joe

Scalable architectures and Ruby on Rails

Wednesday, July 25th, 2007

Ruby on Rails has been around long enough to get past most of the hype. It is a robust web app framework with a lot to offer. One big drawback seems to be the general lack of performance that many rails apps have. Well, it turns out that there are several things that can be done for that.

First off, go read Charlie Savage’s article on tips to tune your rails app. Charlie discusses profiling your ruby app, and then tracking down the problem areas that are hurting performance. He was able to get his response times down from 7.8 seconds to 0.92 seconds! Wow.

Ok, so what about the case where you’ve tweaked your app, and wrung every last bit of performance you can out of it? But it still isn’t enough. You still cringe everytime your site makes the digg front page. Well, if you have your own servers, you can ensure that you have a scalable architecture. Theo Schlossnagle has a great book on the subject, Scalable Internet Architectures. This book discusses the various issues that a system designer faces when organizing the hardware that a web app will run on. Things like having optimized “static content servers” to stream image assets and css, along with more advanced techniques like setting up a caching proxy for each of your application servers since their CPU time is precious, and should not be wasted shoving content down a slow bandwidth pipe. He also goes into basic database design and advanced logging techniques.

Almost all of the techniques that Schlossnagle talks about are for larger installations, however he also spends time talking about scalability. Particularly the need to be able to scale down as well as up. For example, let’s say you are a fresh new startup, flush with VC cash. You go buy twenty servers, and fill ’em all up with world changing web 2.0 goodness. Six months later realize that the money will run out four weeks before the next version is ready to launch! wouldn’t it be great to be able to consolidate everything onto one or two servers, sell the others, and keep yourself in business a bit longer, until you can get version two out the door? If you designed your software and hardware with both kinds of scalability in mind, you might just stick around long enough to see version three.

So how does all this fit into Railspace? Well, first off, design your application so different bits can be spun out onto separate application servers. Perhaps even allow for logical breaks in the database. Tune your app to get as much bang for each buck as possible. Look at bottlenecks, both at a software, and hardware level. Know the difference between performance and scalability. Know that tuning your software helps with performance, but that scalability is what handles the digg effect. With this knowledge in place, you can be better equipped to handle all the traffic your heart can desire. Ruby on Rails is perfectly capable of handling anything that comes its way, but it does require planning, and work. Building a scalable architecture for Rails to sit on allows all the benefits to shine.

-Joe