Category Archives: Technical

Rails and Ext non-Ajax Signup Form with Password Confirmation

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This is, uh, a technical post.

Probably there are others who want to do the same somewhat senseless thing: use Ext to do form validation while keeping a boring non-Ajax post-and-response. The bottom line is that Ext favors doing it the Ajax way, and the Ajax way isn’t that hard to set up with Rails (just handle the form submission as normal but return JSON or XML to signal success or failure). But if you’re like me and working on a deadline, there can be a cognitive burden to switching to Ajax posting that you might want to avoid. Paradoxically, you might find yourself wasting a lot of time trying to figure out how to do it the “old-fashioned” way. Well, here’s one working standard-submission Signup Form, with fancy validations and all the kinks worked out.

Here’s the top half of the file users/new.html.erb, which is nearly the same as the code generated by restful-authentication:

<% @user.password = @user.password_confirmation = nil %>
<%= error_messages_for :user %>
<div id="no-js-form">
    <% form_for :user, :url => users_path, :html => {:id => "signup-form"} do |f| -%>
    <p>
        <label for="login">
            Real Name
        </label>
        <br/>
        <%= f.text_field :name, :id => "signup_name_field" %>
    </p>
    <p>
        <label for="login">
            User Name
        </label>
        <br/>
        <%= f.text_field :login, :id => "signup_login_field" %>
    </p>
    <p>
        <label for="email">
            Email
        </label>
        <br/>
        <%= f.text_field :email, :id => "signup_email_field" %>
    </p>
    <p>
        <label for="password">
            Password
        </label>
        <br/>
        <%= f.password_field :password, :id => "signup_password_field" %>
    </p>
    <p>
        <label for="password_confirmation">
            Confirm Password
        </label>
        <br/>
        <%= f.password_field :password_confirmation, :id => "signup_password_confirmation_field" %>
    </p>
    <p>
        <label for="password_confirmation">
            Role
        </label>
        <br/>
        <%= f.select :role, [["consumer","consumer"],["vendor","vendor"]], :id => "signup_role_field" %>
    </p>
    <p>
        <%= submit_tag 'Sign up', :id => "signup_submit_button" %>
    </p>
    <% end -%>
</div>
<div id="js-form-panel">
</div>

The only differences are a div wrapping the form (“no-js-form”) and the “js-form-panel” at the end. You’re going to laugh at me, but this form is buzzword-friendly; it’s unobtrusive in an ugly way. If javascript is turned on, the form will work, and the following will fail:

<script type="text/javascript">
    /* 
     Thanks to:
     http://www.extjswithrails.com/2008_03_01_archive.html for standardSubmit tip (hard to find!)
     http://extjs.com/forum/showthread.php?t=23068 for password confirmation
     Anyone else I stole semantics from
     */
    // Look, I'm copying over the authenticity token to send in the JS-generated form. LOL!
    var authenticity_token = document['forms'][0]['authenticity_token'].value;
 
    Ext.onReady(function(){
        $('no-js-form').hide();
 
        var myForm;
 
        function submitHandler(){
            form = myForm.getForm();
            form_as_dom = form.getEl().dom;
            form_as_dom.action = form.url;
            form_as_dom.submit();
        }
        myForm = new Ext.form.FormPanel({
            monitorValid: true,
            standardSubmit: true,
            url: "/users",
            applyTo: "js-form-panel",
            title: "Signup as a New User",
            width: 310,
            autoHeight: true,
            items: [new Ext.form.TextField({
                allowBlank: false,
                msgTarget: 'side',
                name: "user[name]",
                id: 'js_signup_name_field',
                fieldLabel: "Real Name"
            }), new Ext.form.TextField({
                allowBlank: false,
                vtype: 'alphanum',
                msgTarget: 'side',
                name: "user[login]",
                id: 'js_signup_login_field',
                fieldLabel: "Username"
            }), new Ext.form.TextField({
                allowBlank: false,
                vtype: 'email',
                msgTarget: 'side',
                name: "user[email]",
                id: 'js_signup_email_field',
                fieldLabel: "Email"
            }), new Ext.form.TextField({
                allowBlank: false,
                inputType: 'password',
                vType: 'password',
                msgTarget: 'side',
                name: "user[password]",
                id: 'js_signup_password_field',
                fieldLabel: "Password"
            }), new Ext.form.TextField({
                fieldLabel: "Password Confirm:",
                allowBlank: false,
                inputType: 'password',
                name: "user[password_confirmation]",
                initialPasswordField: 'signup_password_field',
                vType: 'password',
                msgTarget: 'side',
                id: 'js_signup_password_confirmation_field',
                fieldLabel: "Confirm Password",
                validator: function(value){
                    return (value == document.getElementById("js_signup_password_field").value) 
|| "Your passwords do not match";
                }
            }), new Ext.form.Hidden({
                name: "authenticity_token",
                value: authenticity_token
            }), new Ext.form.Hidden({
                name: "user[role]",
                value: "consumer"
            }), ],
            buttons: [{
                handler: submitHandler,
                text: "Signup",
                formBind: true
            }]
        });
 
    });
 
</script>

The noteworthy steps are: first, I hide the ‘no-js-form’, then I copy the authenticity_token that gets generated by a rails form to put in the js-generated form. Then, standardSubmit : true is the config option that makes a FormPanel not submit as an XmlHttpRequest. The funny code in the submitHandler is getting the underlying form object and calling submit on it, but as I write this it doesn’t make sense why both would be necessary. Finally, formbind : true causes the submit button to be deactivated while there are failing validations, and there’s some handy code for making sure that the password_confirmation matches password (totally lifted from somewhere else, see above).

Apple Cocoa Cavil

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I’m going to try to sound more like Andy Rooney1 up here on this blog. Also, how about I indicate when the boooring technical notes begin and end with technical and interesting.

This is one of my favorite xkcd comics. It really speaks to my experience. Usually I can pull away before I’ve finished registering for comments. Sometimes I’m halfway through a closely reasoned argument when I realize how perfectly pointless and non-personal-goal-advancing my actions are. Then, in the worst case scenario, there I am mixing it up with the other comment-warriors. Here’s me windmilling my way through a post about dolphin killing on Japanprobe. This used to be the url for a pitched brawl in which I interjected a few uninformed comments. Etcetera.

Anyway, I thought I’d write this post at a more meta level to dissuade myself from commenting elsewhere. So here goes (technical):

Have you ever noticed that Objective-C is really, really weird? Like, they just took all the C- and C++- style conventions and changed them? Me too. And on top of that it’s compiled and you do memory management and the engineers make APIs that have objects called NSCamelCasedFactoryMethodObjectFacilitator2. Okay, so then someone makes a script-y dynamic thing for managing the Objective-C stuff, good idea. And when designing this scripting interface they make the following language syntax design decisions:

Finally, the instruction separator is a dot, like in English sentences:
myString := ‘hello’.

The following example shows how to send a message to an object:
myString class

See, this is funny, because it’s completely different from every other programming language3. That is all.

Umm, but there is a somewhat interesting take-away. Both Apple and Microsoft have designed really sucky APIs (in terms of intuitability rather than functionality) , compared to which GTK is fairly sane (it gets a bit clunky when dealing with “GtkIter” operations). But the MacOS developers follow Apple’s improvements of this API, cooing over the increased simplicity afforded by the new NSMakesYourToastRegistry. It’s the same with new C#/ Windows API developments. So (this is actually the interesting part) the lesson is that when people work within a “closed” development system, they lose their sense about good and bad design!4

Here’s the idea. Closed development systems don’t get good feedback and don’t have good change mechanisms, so even very good engineers (probably Apple’s are some of the best) end up working in the dark a little. It gets all culty, because there’s an elect that makes the design decisions and a laity that passively learns the new scripture. And everyone’s straining so hard to understand what the design class hath laid down that they’re no longer perceiving the design objectively. And proprietary lock-in helps, because it leads to fatalism (“what can I do, switch to Windows?”). There are all these weird little island communities where the natives are effectively locked-in to a platform because they’ve already invested the energy to understand its weird design. This isn’t even necessarily a proprietary vs. opensource thing. There are strange over-designed opensource projects that aren’t particularly open because of this class division (and most opensource projects rely on only 1-3 main contributors, it seems). All I’m saying is that bad APIs / development languages happen when designers aren’t being influenced in the right way by the end-user developers, and I’m speculating that this has to do with particular attitudes and processes associated with proprietary code and also a kind of design elitism. I mean, doesn’t Objective-C code (as code) suck?

---

  1. I include this link because I think this already marginal reference will become incomprehensible in ten years.[back]
  2. Yeah, I’ve got their number all right.[back]
  3. Actually, these are pretty interesting design decisions. The := assignment syntax is wack, but probably necessary for named arguments or something. The dot on the end is okay, but you’re moving the OO-messaging operator into the generally useless semicolon position. By using the space for messaging, you’re now saying “subject verbs(args)” instead of “subject.verb object, args” (in Ruby you can omit the parens for a function). [back]
  4. So I sort of believe that. Mainly I’m bitter because I can’t get some code to work on MacOS.[back]

Example

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An instance of obsessive behavior: trying out various WordPress themes, tweaking the CSS to look right, making sure the code highlighting is the same color as my gvim theme. Perhaps for hours. This by way of giving myself permission to stop.

Setup for Alexandria Development: Part II

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(…after too much grief today installing Mephisto and mucking with Apache virtualhosts; I’ll get Part I back from the ether eventually) Update: Done. Update: This is a post moved over from the short-lived Mephisto blog, and ported back in time.

First of all, the alexandria binary is just a ruby script that does a require ‘alexandria’ and runs Alexandria.main.

Alexandria.main is a method on the Alexandria ‘module’ that is used throughout the code (modules are ‘namespaces’ to avoid naming conflicts). This method is found in lib/alexandria.rb:

As you should be able to see, this method isn’t doing anything but setting up some global variables (like $DEBUG) and logging, and doing something weird with http_proxy. The real line is Alexandria::UI.main. That’s in lib/alexandria/ui.rb:



module Pango
  def self.ellipsizable?
    @ellipsizable ||= Pango.constants.include?('ELLIPSIZE_END')
  end
end
 
module Alexandria
  module UI
    def self.main
      Gnome::Program.new('alexandria', VERSION).app_datadir =
        Config::MAIN_DATA_DIR
      Icons.init
      MainApp.new
      Gtk.main
    end
  end
end



Gtk.main is the main loop of a gtk program. You set up your windows and widgets before running it, and it makes them all spin until you exit. So, after Icons.init runs (guess what that does), MainApp.new does all the work from now on.


The Pango code above this is interesting for seeing some Ruby syntax and features. Pango is a text-rendering and layout library inside gtk. The code is adding an elipsizable? “question” method (return true/false) to the Pango module. self.elipsizable? means that it’s defining a class method, a method on a class that doesn’t depend on instance data. ||= is a way of saying, “set the variable to this unless it’s already been set to something else (ie, it’s not nil)”.


Unfortunately, MainApp.new is in the massive MainApp class at lib/alexandria/ui/main_app.rb. This class does a lot (too much). The main thing it does is handle all the callbacks from the main window and its widgets. Let’s just take a look at the top:



 
module Alexandria
  module UI
    class MainApp < GladeBase
      attr_accessor :main_app, :actiongroup, :appbar
      include Logging
      include GetText
      GetText.bindtextdomain(Alexandria::TEXTDOMAIN, nil, nil, "UTF-8")
 
      module Columns
        COVER_LIST, COVER_ICON, TITLE, TITLE_REDUCED, AUTHORS,
        ISBN, PUBLISHER, PUBLISH_DATE, EDITION, RATING, IDENT,
        NOTES, REDD, OWN, WANT, TAGS = (0..16).to_a
      end
 
      # The maximum number of rating stars displayed.
      MAX_RATING_STARS = 5
 
      def initialize
        super("main_app.glade")
        @prefs = Preferences.instance
        load_libraries
        initialize_ui
        on_books_selection_changed
        restore_preferences
      end
    #... snip
    end
    # ... snip
  end
end



A couple points here. MainApp inherits from GladeBase. The attr_accessor is a declaration that makes the @main_app, @actiongroup and @appbar instance variables publicly readable and settable. super(“main_app.glade”) calls the initialize method on GladeBase with the glade file that contains the definitions for all the widgets Alexandria uses. The names of the methods tell you about what they do (good!). Because these methods need to know about what the user’s preferences are, @prefs has been made available before they are called.


To understand what MainApp is doing, it seems like we need to understand what GladeBase is.



module Alexandria
  module UI
    class GladeBase
      def initialize(filename)
        file = File.join(Alexandria::Config::DATA_DIR, 'glade', filename)
        glade = GladeXML.new(file, nil, Alexandria::TEXTDOMAIN) { |handler| method(handler) }
        glade.widget_names.each do |name|
          begin
            instance_variable_set("@#{name}".intern, glade[name])
          rescue
          end
        end
      end
    end
  end
end



So GladeBase is using GladeXML to get the widgets out of the xml file and load them into memory. It then iterates through them, *adding them to MainApp (instance_variable_set is doing the work). So if there’s a widget called @main_menu, MainApp will get this variable to work with. These widgets work exactly as though they had been created “by hand”.


If you’ve been following, take a look at load_libraries and see if the code there makes sense. Here’s a short snippet:



      def load_libraries
        completion_models = CompletionModels.instance
        if @libraries
          @libraries.all_regular_libraries.each do |library|
            if library.is_a?(Library)
              library.delete_observer(self)
              completion_models.remove_source(library)
            end
          end
          @libraries.reload
        else
          #On start
 
          @libraries = Libraries.instance
          @libraries.reload
# ...



This is where things start to get confusing. load_libraries is also being used to reload libraries, so first it checks to see if @library has been defined already (refactoring opportunity). In the normal case, Libraries gets called by by invoking Libraries.instance. To understand this, you have to know that Libraries uses a factory class method to make sure that Libraries only gets created once (making the Libraries instance a “singleton”).


At the bottom of load_libraries is some interesting code:



# ...
        @libraries.all_regular_libraries.each do |library|
          library.add_observer(self)
          completion_models.add_source(library)
        end
# ...



This is telling each library in @libraries (the Libraries singleton) to add self as an “observer”. What does this mean? It means that class Library is “observable”. To see what that means you have to look at Library. First let’s look at Libraries, in lib/alexandria/library.rb:



  class Libraries
    attr_reader :all_libraries, :ruined_books
 
    include Observable
    include Singleton
 
# ... snip
 
    #######
    private
    #######
 
    def initialize
      @all_libraries = []
    end
 
    def notify(action, library)
      changed
      notify_observers(self, action, library)
    end
  end
end



Libraries is including the Observable and Singleton modules to give it special methods (in Python these are called “mixins”). Singleton gave it the instance method. Observable is giving it the notify_observers method. What this method does is “call up” all the observers of this instance by calling their update methods.


Libraries has many Librarys (it’s a little weird to give a class a plural name). Each library is an observer of Libraries. Library is also Observable:



 
  class Library < Array
    include Logging
# ...
    include Observable



As we saw above, MainApp adds itself as an observer to each library. If you look on MainApp you’ll see that it has an update method:



def update(*ary)
# ...
  end



*ary means that it accepts an array as its argument. This method gets called from many places in Library, like this:



        source_library.notify_observers(source_library,
                                        BOOK_REMOVED,
                                        book)



That’s all for now. To learn more about Observers read this.

Setup for Alexandria Development: Part I

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This is the first in a series of brain-dumps of my knowledge about Alexandria and related development issues. Be warned, the approach I will take in these posts will be to discuss boring and perhaps obvious details as they occur to me. You are advised to skim.

Getting the code

First things first, you should be able to checkout a copy of Alexandria from subversion. You can find instructions here, but unless you want to pull down the entire tree this is the actual URL you want:

svn co svn+ssh://method@rubyforge.org/var/svn/alexandria/trunk/alexandria

Btw, this is worth looking at if you want to play around with code without committing to a central repository.

Initial setup

Let’s look at the directory structure of the checked out copy (called the working directory).

(alexandria root)
alexandria.desktop.in (Used to add Alexandria to the Gnome menu)
Rakefile                         (The `rake` command looks for this)
/spec                            (Specs go in here)
alexandria.xcodeproj        (MacOS XCode project file)
/data                            (Configuration files go here)
/lib                               (Alexandria code libraries are here)
tasks.rb                        (Rakefile uses this file)
/bin                              (Actual system-wide alexandria command goes here)
/debian                         (Contains templates needed to create debs)
/tests                           (For old 'test/unit' tests)
/doc                             (Docs go here)
/po                               (Language files go here)
/schemas                       (Used in gconf, configuration file like Windows registry)

You will need to get a copy of rubygems. For some reason, the Ubuntu packaged rubygem never seems to actually work, so you should just compile and install rubygems from here. On Ubuntu or Debian, you should run sudo apt-get install build-essential ruby1.8-dev because some gems will need to build “extensions”. You can use either your distro’s rake or install rake from gem. You install gems with:

sudo gem install (package)

You should install rake, rspec, rcov and zentest (autotest):

sudo gem install rake rspec rcov zentest

To work on the website you will also need staticmatic.

Rake and Testing

In the root of your working directory you should now be able to type rake -T and you will see a long list of rake “tasks” defined in the Rakefile and tasks.rb. The most important tasks for development purposes are sudo rake install to install to your system (it installs in /usr/lib/ so be careful) and rake spec, for running the test suite.

Rspec is super cool, but you’ll have to study the tutorials to learn how to use it. A great way to learn Ruby and Rspec at the same time is to ‘spec out’ basic Ruby types! For example, if you’re unsure about how an array method works, you can do this:

describe Array do
   it "should sort strings alphabetically" do
      ["b", "a", "c"].sort.first.should == "a"
   end
end

Just don’t get confused by the pattern of writing specs to cover code that’s already been written. The basic idea behind Behavior-Driven Development is that you write tests that show how your code will behave before writing the code. The only way to really learn how to do this is to force yourself to write some code this way.

Because BDD is supposed to happen before you write code, Alexandria has very poor test “coverage” at the moment, and its not easy to add specs to the code the way it is now. Still, it’s good practice to try and understand the behavior of a method on a class and write a spec for it. Take a look at the files in specs/alexandria for examples.

When a project has good test coverage it’s possible to work according to a very fast “red-to-green” development cycle. Autotest is a tool that will run ‘rake spec’ every time you change a file that’s being monitored. This is great because, again if the test suite is good, you can know the second you break the code! It’s even better if you use desktop notifications with Autotest. This is the version I use with Ubuntu Gutsy. One note: the file he links to is only good for Gentoo, you want this one.

That’s all for now. I’ll do another one tomorrow.

What’s this?

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I just got this at the top of a search for “ruby rake” on Google.

Ruby — Rake: 4
According to http://jimweirich.umlcoop.net/index.cgi/Tech/Ruby - More sources »

The url under “More sources” goes here. All I can figure is that this is some kind of authority thing, or like the wtf feature on Technorati. jimweirich is a 4 or something. Maybe this is nothing, or maybe this is the beginning of semantic categorization on Google!!! ??? Why is this important? Well, if you search for Martin Luther King, one of the top links goes to a white supremacist hate page. It may be that Google is moving away from its raw algorithm, which can be gamed, and toward a trustweb system. Actually, it just occurred to me that that result could be from the Google search results tagging system that is already in place. So, is this old news?

religion.

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12:00 PM me: Does [your company] use whitespace or tabs?

12:01 PM Ian: you mean spaces?

everyone uses spaces.

four spaces, in fact.

It’s Guido gospel.

me: But spaces suck.

12:02 PM Ian: not even remotely.

me: I know that’s the gospel, but it doesn’t make sense.

Ian: It makes excellent sense.

Easier to deal with. Only one kind of whitespace.

me: Do Windows and Linux use different tab characters?

Ian: no.

12:03 PM me: Dude, two-space tabs.

Google uses two-space whitespace, btw.

Ian: well, nobody else does.

me: I know. It drives me crazy.

12:04 PM

Ian: I like four. Everything lines up properly.


def myfunc():
____blah

me: Eh. I use two-space tabs in Ruby, and I don’t like to change when I program in Python. Gajim uses tabs, though.

Ian: We were never told this, it’s just the general rule.

12:05 PM me: Well, it’ll break if you mix them.

Ian: I am aware.

me: That’s retarded.

Ian: Not really. It has to break.

12:06 PM me: I know, but it’s still retarded.

12:07 PM

Ian: I mean, it’s been the standard forever. Tabs are bloody annoying, since they look like spaces but aren’t.

me: But tabs are semantic! Just turn on printer’s symbols if it bothers you.

12:08 PM What’s annoying is backspacing and it goes back…one…character…at...a..time.

12:10 PM I swear, future generation will look back on this as utter madness.

 6 minutes

12:17 PM Ian: well. I don’t have to do that.

Vim does tht for me.

12:18 PM me: I thought so.

Ian: it backspaces a tab at a time if appropriate, otherwise space. It’s perfectly natural.

me: Well, that’s not so bad.

Ian: but my code will always render in exactly the same way on everyone’s machine. Lines will have the same length.

12:19 PM if it’s 79 chars, it won’t wrap on somebody else’s editor who has their tabs set to 8 or something

me: I’m right, though. But it is utter gibbering insanity.

What is sacred in web pages is verboten in code. This is ridiculous to me.

12:20 PM Ian: what is sacred in web pages?

whitespace is ignored.

me: Tab means indent!

Ian: tab doesn’t mean a damn thing in a web page

me: User sets the indent!

I know. Using space is like using <br /> in webpages.

12:21 PM You’re trying to control display.

And you call it a virtue.

Ian: well, yeah. html isn’t for content.

me: Madness.

Ian: indentation is set in CSS

me: Yes!

That’s my point.

12:22 PM Tab means <indent />

Ian: But it doesn’t.

In a web page, “beginning of paragraph” means <indent/>

12:23 PM there’s no tabbing.

You can’t artificially insert a tab character.

me: If someone said, don’t use <p>, use <br />, some users change the margins on paragraphs, you’d say he was an idiot.

Ian: You can’t double-tab.

no users change the margins on paragraphs. My own CSS does.

me: I understand. I’m saying tab means indent, a semantic element. It means level of scope in Python.

12:24 PM Ian: but it doesn’t. whitespace means level of scope.

me: But if they wanted to, they could. Then it wouldn’t display properly. Best to use <br />

Ian: no, they couldn’t.

me: Ahh!!!

12:25 PM Yes, they could. They could change the default stylesheet, and make it !important.

Ian: The end user doesn’t control the display of a web page, except for text size.

me: Ugh.

They have a degenerative sight disorder that requires the paragraphs to be widely spaced.

12:27 PM I’m saying the principle that is sacred in web pages is considered a liability in code, and only really in Python and shell scripts, because indentation is just for looks in C++, Ruby, Java, etc.

Ian: But no one will ever do that. I don’t understand how this is at all relevant. Code display has nothing to do with layout. The goal is to do it the same way as everybody else.

and that sacred principle is…?

i still don’t get it.

Since there are no tab characters in web pages.

12:28 PM me: Let the user determine presentation. That’s the principle. If they want to apply another stylesheet that makes your page look stupid, so be it.

Ian: But that isn’t a sacred principle in web pages.

me: Yes it is.

It’s why we don’t use tables and <br /> for everything. It’s why we don’t compose web pages in Word.

12:29 PM Ian: No, it isn’t.

We don’t do it that way because it’s extremely limited.

And it won’t display the way /we/ want it to.

me: Dude, wtf? Use flash if you want to control display.

12:30 PM Ian: But that’s totally wrong! That’s warped!

me: I understand that the user usually views a page the way you want him to.

But he doesn’t have to.

Ian: Always. Unless they’re hacking it.

In which case I don’t care.

12:31 PM Build the page to deal with big text and small viewports, but otherwise whatever.

me: What are you talking about? They can view a page in Lynx, or with a screen reader, or using a Greasemonkey script, or whatever.

12:32 PM

Ian: There aren’t other variations, except for the extreme outliers where people hack your CSS.

me: If it’s important to have code displayed with a certain size tab, you could include a hint at the top.

Ian: People using greasemonkey scripts know the page will be fucked up. Lynx doesn’t apply, since it strips CSS. Screen readers are a completely different thing.

12:33 PM me: I am horrified.

Ian: I dunno where you get this insane idea.

me: I don’t know why you’re fighting me on this. The whitespace thing, sure. But not this principle.

12:34 PM Ian: You can’t account for all users. Especially not if they are making up their own CSS.

me: <br />This is a paragraph.<br /> See, it’s better? Works every time, no matter what the user does.

Ian: It’s impossible to predict that.

Except you can’t do anything. That’s idiotic.

12:35 PM me: Yes, because it’s attempting to define display with markup.

Ian: but <p> tags aren’t for the benefit of the user

they are boxes with default CSS that you, the designer, change.

12:36 PM They’re roughly semantic, but you don’t use them wherever you have text.

me: Okay, I get you.

But a screen reader would use the paragraphs to know where to pause, for example.

Ian: They certainly don’t mean “paragraph,” and they’re only indented if you explicitly set text-indent.

If it’s a screen reader, you have a different style sheet

12:37 PM me: Yes!

Ian: and you use pause-before:blah

in the CSS

me: Do you define a css audio stylesheet for your pages?

Ian: Hell no.

me: So they use the default settings.

Ian: Certainly not for [my company].

12:38 PM me: It’s whatever they want.

And you can override stylesheet settings with !important.

Ian: Also it strips out all layout, so it’s irrelevant.

me: Huh? That’s layout. It doesn’t read them in any order.

12:39 PM Ian: WHO can?

The blind greasemonkey users?

me: Yes.

Ian: I will never, ever design a page for a blind greasemonkey user.

me: Argh.

Please see the analogy.

12:40 PM

Ian: I see what you’re getting at, but I think you’re totally wrong.

The user /can/ define presentation, but only by /breaking/ the original code and rewriting it.

Or using an application that discards certain things, like a screen reader.

me: “As god is my witness, I will never allow another programmer to view my code at anything but four spaces to an indent level. I would rather die.”

Ian: Or lynx.

12:41 PM So if you really want to, you can, before editing any code, translate all spaces into tabs, then do your editing, then retranslate and save.

That is roughly comparable.

It’s a simple greasemonkey script.

me: You’re saying it’s something freaky, because it’s rare. But it’s just rare. It’s something that’s built in to html.

12:42 PM

Ian: if you just have to have your indentation be a certain width, you can. But who the hell cares? The end user of code is the computer.

You make it useful for future coders, of course

me: You do know that all the CSS Zen Garden sheets refer to the same page, right?

Ian: Make it readable and whatnot

Yes.

It’s a basic HTML structure.

12:44 PM divs with some ps and uls

me: Anyways, I can’t change the whitespace to tabs. People would yell at me.

Ian: Well, then you change it back, before saving.

me: Whywhywhy?

Ian: Because code isn’t written for you.

It’s written for everyone.

12:45 PM I take that back: it isn’t written for anyone.

it’s written to be run.

You make it readable, not pretty

more to the point: you make it /editable/

12:46 PM (which web pages aren’t)

me: What’s so bad about tabs??? They only occur at the beginning of the line. If there’s one, it means one level of indent, two two levels, etc.

If the user chooses to view them at 4 spaces per tab, they display like that, if 2, then that.

12:47 PM

Ian: Nothing in particular, except it’s a whole nother character to deal with. If “whitespace=space” it’s easier.

From a coding perspective.

I don’t have to wonder if there are tabs anywhere, because they’re all spaces.

12:48 PM me: The thing is, it doesn’t even matter in Ruby! I can write the whole script without any beginning of line spaces at all! It’s only Python that cares! And Guido bases it on the C++ coding standard, where it also doesn’t matter!

Ian: If I want to indent only one space, I can.

If I want to line up my dictionary values, I can.

12:49 PM me: In Gedit, tabs are arrows and spaces are dots.

Ian: If you turn that shit on. But most people don’t. Most people use emacs and vim.

me: Well, okay, there’s something.

12:50 PMThings only get out of whack if you mix tabs and spaces, it’s true.

Ian: mostly it’s just annoying to have arrows and dots scattered throughout your code.

me: It makes it clear for me.

12:51 PM I don’t understand why “knowing if whitespace is a tab or a space” is more important than knowing that you haven’t accidentally backspaced and set a line to three space indent instead of four.

That happens all the time.

12:52 PM Ian: that never happens.

I have autoindentation on.

me: It’s happened to me. It’s happened in code that I’ve downloaded.

Ian: Then someone wrote it poorly.

12:53 PM That happened to me when I used gedit, which is a stupid application.

or notepad or something.

me: All this effort for a marginal problem of “knowing whether a character is a whitespace or tab” when it introduces another marginal problem.

Ian: But there are no problems.

12:54 PM My code is always clean, no matter who looks at it.

me: Just like there were no problems with the five year plans!

Umm.

12:55 PM Ian: Unless they have their line width set to something short. But then they would be an iiot.

idiot

me: Google uses two spaces! Four spaces is too much!

12:56 PM Ian: Google uses two spaces because fewer spaces translate into less downloaded.

me: Let the programmer decide!

Ian: Any web programmer worth his or her salt packs their code before uploading.

12:57 PM me: No, because code shouldn’t be nested beyond more than two or three levels anyway.

So it should be easy enough to read at two spaces.

Ian: ?

12:58 PM I mean, yeah, code rarely gets that deep

Except not really, when you have vars inside functions inside functions inside classes.

me: Most Ruby code uses two spaces and it’s easy to read.

12:59 PM About four or five levels.

Ian: Well, if Ruby takes over the world, perhaps other people will do it that way.

Using xsl to import a phpmyadmin xml file

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Yep, following the last post I have to explain what I just did for the LazyWeb1 . This is going to be boring and technical, folks.

If you’re like me, you’ve exported a MySQL database as an xml file through PhpMyAdmin. In general, you shouldn’t do this. You want the SQL file. I don’t entirely understand it, but phpmyadmin does not import the format that it exports. If you throw away the database, you’ll be stuck with an xml file that can’t be easily imported. Okay, and if you already threw away the database? In my case, it’s an old Texpattern db that I want to get into a WordPress db, so if I can just get it into RSS form I’m home free. Here’s what you do:

  • Take a look at this explanation of XSL (XML Stylesheets).
  • Create an XSL stylesheet like this (name it stylesheet.xsl for this example): 
    <?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/">
<channel>
<title>Stupididea</title>
<link>http://www.stupididea.com/</link>
<description></description>
<language>en-us</language>
<xsl:for-each select="stupidid_text/textpattern">
<item>
<title><xsl:value-of select="Title"/></title>
<link></link>
<description><xsl:value-of select="Body_html"/></description>
<dc:creator><xsl:value-of select="AuthorID"/></dc:creator>
<dc:date><xsl:value-of select="Posted"/></dc:date>
</item>
</xsl:for-each>
</channel>
</rss>
</xsl:template>
</xsl:stylesheet>
  • Include a line like this at the top of the xml file you exported from phpmyadmin: 
    <?xml-stylesheet type="text/xsl" href="stylesheet.xsl"?>
  • Open an xsl-aware browser (most of them) and try to save the page as an rss file. Note: this was quirky for me. Sometimes the browser would just save the original file, sometimes it would save the stylesheeted output. Try with different browsers.
  • (WordPress) Import the RSS file after checking that it is valid.

This is the general solution for any case where you can recover your database by transforming the phpmyadmin xml into an importable format. You’ll have to play around with the options based on your use-case.

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  1. Ironically, there doesn’t appear to be an entry on Wikipedia for Lazyweb. I understand it as asking on your blog for help with answering a question (“Dear Lazyweb, …”), i.e., you’re too lazy to research the topic yourself. I’m extending the concept of LazyWeb here to include the posts and forum threads that help you when you’re out googling for a solution to a problem. [back]