Polymorphism

Does exactly what it says on the tin

Chris Peters — Sat, 06 Feb 2010 18:39:57 +0000

“Does exactly what it says on the tin.”

I love it. All of our method and function names should do exactly the same.

During a discussion with the ColdFusion on Wheels core team about the valid() and beforeValidation() methods, Andy Bellenie made this remark:

My point is that a callback called beforeValidation should run, well, before validation – not during it. This seems self-evident to me and I’d have a hard time explaining to anyone why it should work differently.

Then he pointed to “the Ronseal test, the holy grail of method naming.”

Thanks Andy for the inspiration.

Technorati Tags: best practices, cfwheels, chris peters, clear crystal media, ColdFusion, coldfusion on wheels, development, polymorphism, Programming, web development

First step in throwing your XHTML document into Quirks Mode

Chris Peters — Thu, 31 Dec 2009 15:24:38 +0000

A lot of websites pursue XHTML as their document type, which is really cool. But a lot of them end up not validating with one little mistake. Even worse, with this mistake, documents that are made to run in “standards mode” are immediately thrown into quirks mode by browsers because web developers don’t know how to do their jobs.

If you want to author XHTML documents, your DOCTYPE declaration must start on the first character of the first line of the source code. No leading spaces or line breaks.

My favorite is how ASP.NET breaks this by following their practices. Take the example from Wikipedia (which I’ve seen used elsewhere as well):

<%@ Page Language="C#" %>   
 
DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

This causes developers to insert 2 line breaks before the DOCTYPE, which is unacceptable if you want to comply with standards.

Because my weapon of choice is CFML, here’s how I handle this situation using and tags in my layout files:

<cfsetting enablecfoutputonly="true">
 
<cfparam name="layout.title" type="string">
<cfparam name="otherParams" default="here">
 
<cfset variablesThatNeedSet = "here">
 
<cfoutput>
<head>
<title>#layout.title#title>
...
head>
 
cfoutput>
 
<cfsetting enablecfoutputonly="false">

Because ColdFusion suppresses output until the opening tag, the DOCTYPE will appear on the first character of the first line, right where it belongs. And browsers will treat the document as standards compliant, not in quirks mode.

Technorati Tags: asp.net, ccm, cfml, chris peters, clear crystal media, ColdFusion, html, polymorphism, quirks mode, railo, standards, standards compliance, web standards, xhtml

Up and rolling with Git on Snow Leopard

Chris Peters — Sat, 28 Nov 2009 15:34:42 +0000

This morning, I set up a GitHub account so that I could have some public repositories for my ColdFusion on Wheels plugins. Feel free to follow me and watch my repositories as I post them up. (Gotta learn how to do that first though!)

Then came the process of installing Git on Snow Leopard so that my computer can talk to the repository. In my opinion, the Git website could do a better job with their Mac OS X installer (or at least the instructions).

Fortunately, Hivelogic has a great step-by-step on installing Git on Snow Leopard. If you’re running Snow Leopard, I highly recommend doing everything that they say in the post. If they ask you to touch your nose while spinning in circles, do it.

Now on to figuring out how to get my reCAPTCHA on Wheels plugin into my new repo.

Technorati Tags: ccm, cfwheels, chris peters, clear crystal media, coldfusion on wheels, Git, github, install, installation, polymorphism, scm, version control, web development

Using extra CFC attributes for documentation

Chris Peters — Thu, 12 Nov 2009 21:57:02 +0000

For the ColdFusion on Wheels API documentation, we chose to do something a little unconventional (but pretty cool). Instead of trying to write or use a comment parser for our documentation, we just added additional attributes to our CFCs’ tags.

Look at this example for the autoLink() view helper:

<cffunction name="autoLink" returntype="string" access="public" output="false" hint="Turns all URLs and e-mail addresses into clickable links."
    examples=
        '
            ##autoLink("Download Wheels from http://cfwheels.org/download")##
            -> Download Wheels from http://cfwheels.org/download
 
            ##autoLink("Email us at info@cfwheels.org")##
            -> Email us at info@cfwheels.org
        '
    categories="view-helper,text" functions="excerpt,highlight,simpleFormat,titleize,truncate"
>
        <cfargument name="text" type="string" required="true" hint="The text to create links in.">
        <cfargument name="link" type="string" required="false" default="all" hint="Whether to link URLs, email addresses or both. Possible values are: `all` (default), `URLs` and `emailAddresses`.">
 
        <cfscript>
            var loc = {};
            loc.urlRegex = "(?ix)([^(url=)|(href=)'""])(((https?)://([^:]+\:[^@]*@)?)([\d\w\-]+\.)?[\w\d\-\.]+\.(com|net|org|info|biz|tv|co\.uk|de|ro|it)(( / [\w\d\.\-@%\\\/:]* )+)?(\?[\w\d\?%,\.\/\##!@:=\+~_\-&]*(?<![\.]))?)";
            loc.mailRegex = "(([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,}))";
            loc.returnValue = arguments.text;
            if (arguments.link != "emailAddresses")
                loc.returnValue = loc.returnValue.ReplaceAll(loc.urlRegex, "$1<a href=""$2"">$2a>");
            if (arguments.link != "URLs")
                loc.returnValue = REReplaceNoCase(loc.returnValue, loc.mailRegex, "<a href=""mailto:\1"">\1a>", "all");
        cfscript>
        <cfreturn loc.returnValue>
 
cffunction>

It makes the function declarations a little beefier, but the documentation is right there with the code. As you can see, we added examples, categories, and functions attributes to the declaration.

Writing a parser took a little over a week, but it was fairly simple with CFML’s GetMetaData() function and some extra business rules.

Here’s a link to the autoLink() documentation on CFWheels.org so you can see what the output looks like. Everything on that page is generated based on the code above.

Technorati Tags: adobe, ccm, cfml, cfwheels, chris peters, clear crystal media, ColdFusion, coldfusion on wheels, polymorphism, railo, web development

Script-based controllers and models, tag-based views

Chris Peters — Thu, 22 Oct 2009 19:41:48 +0000

I’m looking forward to playing around with ColdFusion 9 when I get some more time here in a month or so. One of the areas that interests me in particular is the ability to write full CFCs in CFScript syntax.

Think about this scenario in ColdFusion on Wheels:

Controllers in script syntax
Models in script syntax
Views in tag syntax

I like the idea of this, though I’ll admit that I haven’t tried it yet. The more data- and logic-heavy parts of the app can be script-driven, while the tag-based syntax can be used with HTML.

Imagine this scenario for a Wheels model class:

component extends="Model" {
 
    /**
      @hint Initializes associations and validations
    */
    public function init() {
        // Associations
        hasMany("chirps");
        // Validations
        validatesPresenceOf("firstName,lastName,email,gender,urlId");
        validatesUniquenessOf("email,urlId");
        validatesLengthOf(properties="firstName,lastName", maximum=50);
    }
 
}

And this for a Wheels controller:

component extends="Controller" {
 
    /**
      @hint Shows form for registering for social network.
    */
    public function register() {
        user = model("user").new();
    }
 
    /**
      @hint Saves registration submission.
    */
    public function create() {
        user = model("user").new(params.user);
        user.save();
 
        if(user.hasErrors()) {
            renderPage(action="register");
        }
        else {
            flashInsert(success="Thank you for registering for Social Network.");
            redirectTo(controller="home");
        }
    }
 
}

And then any view logic can be mixed in via tags with all the other HTML tags (right where it belongs).

<cfsetting enablecfoutputonly="true">
 
<cfparam name="user">
 
<cfoutput>
 
<h1>Register for Social Networkh1>
 
#startFormTag(action="create")#
 
#textField(label="First Name", objectName="user", property="firstName")#
#textField(label="Last Name", objectName="user", property="lastName")#
#textField(label="Email", objectName="user", property="email")#
 
<fieldset>
    <legend>Genderlegend>
    #radioButton(label="Male", objectName="user", property="gender", tagValue="M")#
    #radioButton(label="Female", objectName="user", property="gender", tagValue="F")#
fieldset>
 
<fieldset>
    <legend>Profile Addresslegend>
    #textField(label="http://#cgi.script_name#/profile/", objectName="user", property="urlId")#
fieldset>
 
<div>
    #submitTag(value="Register Now")#
div>
 
#endFormTag()#
 
cfoutput>
 
<cfsetting enablecfoutputonly="false">

This makes me excited for Railo adoption of script-based CFCs and for time to warp 5 years into the future when script-based CFCs are more widely used in general.

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