Tuesday, September 22, 2009

If only

"If only I had ____ I would succeed."

These simple words will kill your dreams faster than anything else you could say or think. There are so many self-defeating thoughts that an entrepreneur can have, and they often take this very simple form.

While Garry takes it in the direction of getting your hands dirty and building, and the recent HN discussion talking about whether one should sell or not, reading these compels me to take it in a different direction this morning before work--I'd like to speak a little about mental blocks.

There were many reasons why you'd want to sell your company.  Your business deals with fads and the market will go away.  You're done with this thing and want to move on.  But there is a bad reason I want to focus on:  "it'll give me freedom to do what I want".  I think when people say this, they mean two different things: 1) if I have lots of money to take care of life's annoyances like bills and college tuition, then my mind will be free to work on anything 2) if I have lots of money, I can fund whatever I want to work on.  The latter, I find to be an unconvincing reason.

My dad is retired. He talks about starting a foundation to help education in Taiwan, and seems rather passionate about it.  He spends a lot of time watching and reading Taiwanese news.  Given a chance, he'll talk your ear off about it.  However, he says, "if only I had a million dollars", he could start his foundation.  And the way he usually thinks of getting the million dollars is through the lotto.  Now, my dad is no fool.  He knows the odds.  And I don't know if it's a generation gap in the way jokes are told, but if he's serious, it's a mental block that I see in some friends also.  It's an excuse to do nothing because of the preceived notion that the external world hasn't given you permission.

By contrast, a couple years back Oprah had some special on TV about a new school she was building in South Africa.  Though she put in a hefty sum, I was surprised to find out that she didn't put in all the money herself.  She had other people help her with donations.  That's why she had Nelson Mendela, Maria Carey, and others visit the school--to help donate.  Even when she could pay for it all herself, she enlisted other people to help. In a more recent example, Breadpig and xkcd joined forces to put a school in Laos.  They're putting in the work, yes, but as far as I can tell, it's none of their personal money. 

Just because something takes a million dollars to do, doesn't mean it has to be your million. 

Perhaps this is obvious to some of you, but I was a little bit surprised when I realized this.  Growing up, I never thought about it too much, because in movies like Batman, Bruce Wayne funded his own crazy toys.  So I naturally assumed that if you want to do huge things, you do it all with your own money. As a kid, I thought:  If I wanted to build a Mechwarrior, I'd have to do it with my own money.  If I wanted to build a loop-de-loop highway, I'd have to do it with my own money.  If I wanted to build a giant chicken slingshot, I'd have to do with with my own money.

Of course, this comes with some amount of responsibility and constraint.  Pissing away other peoples' millions is a sure way to get your legs broken, especially with money from a loan shark (or its million dollar equivalent).  But I believe constraint in business and philantropy, as constraint in design, is a good thing to focus your efforts.  Sometimes, personal money projects fail because they're not as readily subjected to market forces.  A bad idea is kept afloat because there's a huge chunk of personal money that keeps getting dumped into it.

In the end, I just want to say, you have a choice.  Don't let a little thing like not having a couple million stop you from doing what you want to do, as there's always more than one way to skin a cat.  But if you want to build a pyramid for your burial site, then yes, please do that with your own money.

Posted via web from The Web and all that Jazz

Sunday, September 13, 2009

rake task with arguments - Ruby Forum

Of course csh is evil! That's nothing new. http://ooblick.com/text/CshProgrammingConsideredHarmful.html This works just fine with bash:

rab://tmp $ cat Rakefile
namespace :foo do
desc 'lol'
task :bar, :num do |t, args|
puts "num = #{args.num}"

rab://tmp $ rake foo:bar[123]
(in /private/tmp)
num = 123

Hey look. Arguments in Rake. I've been looking for this for a while now. No more using env variables.

Posted via web from The Web and all that Jazz

Saturday, September 12, 2009

Another bad data visualization

(click image to enlarge)


This is one of the worst data visualizations I've seen.  Problem is it looks pretty, so people send it around, but it's not very informational.  Nor does it allow easy comparison of the data.  First, it's not apparent that the light green and the dark green sections are the same thing until you realize it's an "O" from "Google", and actually adds no information.  Second, what do the size of the circles represent?  Is it combined daily spending or average daily spending per advertiser?  It takes a while to find the circumferencial text, which you'd guess that it represents the amount of revenue from top N advertisers.  Then the chart also mixes terminology.  While spending by advertiser and revenue by google are the same thing, you need to do extra work to figure that out.  Then, what the heck, the list of logos on the side is distracting.  It's suppose to be the advertisers in the blue circle--the top 10 advertisers--but it sits firmly in the red section, which is the long tail of advertisers.  Even more confusing, the $59,184,783 is red, but points to the blue list of logos.  Lastly, the average daily spending is colored with the same position and weight as the combined daily spending, but it doesn't represent the size of the circles, which adds even more confusion.

The only thing they did right was to match the size of the circles with the amount of combined daily spending.  Often times, people will draw these sorts of graphs using the diameter as the basis for comparison, which is misleading.


Posted via web from The Web and all that Jazz

Tuesday, September 08, 2009

Using HTML attributes as a mini-DSL for AJAX

At first, I thought being able to return json as responses from the server was pretty neat, with rjs (now js.erb) files using render :update call in Rails.  However, this often lead to some messy code by me and my colleagues.  I would see lots of client side code in the application controller like:

Sometimes, this is ok, but when html elements change, the controller methods break, and the effect cascades from the views through the controllers.  That's a code smell that our code is tightly coupled.  Of course, we can refactor it to a separate .rjs template file, and justify it to ourselves that it's the same as having an .html.erb file.  However, because .rjs files are often so short, the cognitive shift to find that other file is often distracting, and it still doesn't solve the problem of code coupling.

Consider the following:  You want to have a link that makes an AJAX GET request to get a list of comments for the post when clicked.  It gets the response as HTML and then dumps it in the target DOM.  You also want to fade in an indicator feedback when the ajax is loading and fade it out when it's finished loading.  Lastly, there's to be a slidedown effect on the target comments DOM element.  

For the situation above, if we were to do it with render :update or with rjs files, you'd have code that is coupled with DOM elements as I said earlier.  What if we can contain it all on the client side, and leave the server side for business logic?

One way is to use all the options that link_to_remote provides.  This way, all the UI effects are contained on the client side when you have an AJAX GET request.  We can now keep all our UI effects code in the views.  

However, what if we can declare this effect in HTML?  Would that work?  What are the advantages and disadvantages?

I went to the local Ruby meetup, and remembered that Ben Johnson of Authlogic was mentioning something about "data-" attributes in HTML5 and its relation to the problem I described above.  I wasn't entirely sure what he was talking about, until I looked around for the "data- attribute" and found good ole Resig blogging about it (last year, no less).  

What this allows us to do is basically insert data into our HTML elements.  And because jQuery events let us separate the "how" in javascript from the "what" in html, we can declaratively use it as a mini-DSL of sorts.  

The basics are pretty easy to implement.  I didn't do the data-indicator and the data-effect because I'm lazy and it's left to the reader "as an exercise".

Note that I'm proposing it to be a mini-DSL, so that very common AJAX idioms are covered, and you can simply declare things in HTML and not have to go into the javascript often, if at all.  That way, you keep working in the same file, working on the same level of abstraction.

There are some advantages to doing it this way.  
  1. Server response can be faster, since we wouldn't have to rely on the server to generate the proper html link.  The UI effects and behavior can be all done on the client side, where it should be.
  2. I think it's a bit cleaner to be able to say things declaratively, more aligned with how html is declarative.
  3. The DOM elements wouldn't couple the controller and the view.  Everything that refers to DOM elements would be in the view and be easier to change without cascading effects.
  4. You can work in the same level of abstraction while in the HTML views and won't have to jump between layers of abstraction.
There are few disadvantages I can see right now, other than not having the correct DSL, or having a method call that uses too many attributes, making the HTML hard to read.  (If you have others, comment below)

Pretty neat.  So why use the class attribute as the method "call"?  Perhaps it's better to find some other attribute.  I've seen facebox use the rel attribute instead.  That lead me wonder if other people have thought to do this before.  And of course, there's something similar called AHAH microformat, based on JAH from 2005, which is demoed here.  

JAH does something notable, in that it uses the form:

to order to execute the javascript, instead of binding an event to the DOM.  This removes the extraneous href="#" in the other way I showed you above (more succinct), but it breaks the declarative nature, and cannot be unbound and binded with something else easily--one would have to change all instances it's called, instead of re-adjusting the DOM selector element (as rare as that may be).  I personally don't think it's as easy to read, especially when the method call has parameters, but the implementation would be shorter.

These techniques seem to be by no means widespread at the moment, but one of the contributors is DHH of the Rails fame, so I expect to see it in Rails soon.  So be on the lookout for something similar in the future Rails.  It seems like the technique was talked about back in 2005, but never fully incorporated or used.  I have no idea why.  In the mean time, I intend to incorporate it into new code I write.

(Apologies if there are typos above.  It's late, and I haven't had my ramen)

Posted via email from The Web and all that Jazz

Monday, September 07, 2009

Getting all attributes of a DOM element in Javascript/jQuery

Sometimes, you need to iterate over a number of jQuery elements. You pull something like this:

$.each($(".hello"), function() {
In this context, the "this" variable is actually not the jQuery objects. According to the docs:
Whenever you use jQuery's each-method, the context of your callback is set to a DOM element. That is also the case for event handlers.

This is helpful when you want all the attributes of a particular DOM element. You can call attributes property on the "this" variable (this.attributes) inside of the each() method to get all attributes of each element with the class hello.

Lastly, if you have a jQuery element, you can get all attributes by:


Posted via web from The Web and all that Jazz

Thursday, September 03, 2009

Testing Named Routes in the Rails Console

I finally found out how to do this, from the Rails Routing shortcut by David Black. In the Rails console, do this:

include ActionController::UrlWriter  default_url_options[:host] = 'whatever'  

Then you can call your named route methods directly from the console.

This entry was posted on Tuesday, January 8th, 2008 at 1:58 pm and is filed under Programming, Ruby.You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

I've always just worked around this by trying it out in the templates. Should keep looking things up on google. I learn much more that way. Anyway, thought the rest of you should know also.

Posted via web from The Web and all that Jazz

A tiny empty shortcut

I think I've written about this before, by monkeypatching an empty method on the Array class that takes a block and executes it only if the array is empty.  But anyway, for some of you, you might see something like this taking place often:

To clean it up a little, you can do:

Or else if each of your items is a partial, use the :collection method.

Posted via email from The Web and all that Jazz

Wednesday, September 02, 2009

Expected delayed_job.rb to define DelayedJob

Recently, I needed to do some background processing.  I just needed something simple, and looking at all various options, I decided to go with Bj.  It was fairly simple to understand, and best of all, didn't require another daemon to be running by hand--it started one itself if you didn't configure it.  

However, it's incompatible with SQLServer.  I'm guessing no one's every used it with SQLServer before, since I didn't read anything about it in my research.  Bj uses a column called "key" which SQLServer reserves as a future keyword, and thus, automatically changes the name of the column to "[key]"  So consider yourself forewarned.

Thus, I decided to switch to something similarly simple, and I started using Delayed Jobs.  It's all fine, except in some instances, I ran into the following error:

LoadError: Expected /[RAILS_ROOT]/vendor/plugins/delayed_job/lib/delayed_job.rb to define DelayedJob

After reading around on the web for a while, it seemed like any number of things could cause this error.  I finally found way down in this rails ticket from a while back, had the lines that explained it.

The critical comment at that link is: "Prior to this revision, Rails would happily load files from Ruby’s standard lib via const_missing; you will now need to explicitly require such files."

The rest of the comments also talked about various causes.  It's the case of different problems having the same symptom, and here, the backtrace isn't pointing to where the problem is.  

In the case of Delayed Job, Rails expects delayed_job.rb to define a module or class named DelayedJob.  However, that plugin doesn't have any such class or module.  It defined Delayed::Job instead.  So when loading up dependencies, It's looking for DelayedJob module or class when there is none.  

A workaround is to simply define an empty DelayedJob module in your config/environment.rb file, or feel free to put it in a file under config/initializers if you don't want to pollute your environments file.  Hopefully, that saves you some pain.  tip.

Posted via email from The Web and all that Jazz