My last issue today was to display an error message instead of redirecting to login page when the use doesn’t have permission. Here is a decorator which replace the permission_required of django. Feel free to rename it to avoid confusion

from django.shortcuts import render_to_response
from django.template.context import RequestContext
from django.contrib.auth import REDIRECT_FIELD_NAME
from django.utils.http import urlquote
from django.http import HttpResponseRedirect
from django.contrib.auth.models import Permission

class permission_required(object):
    """
    decorator which redirects to login page if user is anonymous
    and display a permission denied template if user is logged in
    doesn't have permission
    """
    def __init__(self,
                 perm,
                 login_url=None,
                 redirect_field_name=REDIRECT_FIELD_NAME,
                 template='permission_denied.html'):

        if not login_url:
            from django.conf import settings
            login_url = settings.LOGIN_URL

        self.perm = perm
        self.login_url = login_url
        self.redirect_field_name = redirect_field_name
        self.template = template

    def __call__(self, func):
        def wrap(request, *args, **kwargs):
            if request.user.is_anonymous():
                path = urlquote(request.get_full_path())
                tup = self.login_url, self.redirect_field_name, path
                return HttpResponseRedirect('%s?%s=%s' % tup)

            if request.user.has_perm(self.perm):
                return func(request, *args, **kwargs)

            (app_label, codename) = self.perm.split('.', 1)
            perm_name = Permission.objects.get(codename=codename,
                                               content_type__app_label=app_label)

            return render_to_response(self.template,
                                      {'perm': perm_name},
                                      context_instance=RequestContext(request))
        return wrap

My template permission_denied.html contains :

{% extends "base.html" %}
{% load i18n %}

{% block body %}
<h2>{% trans "Permission denied" %}</h2>
<p>{% blocktrans with perm as perm %}You need to have the permission "{{ perm }}"
 to see this page{% endblocktrans %}</p>
{% endblock %}

More information at :

http://2009.rmll.info/Eclipse-Acceleo-Day-Presentation,938.html

http://www.acceleo.org/wiki/index.php/EclipseAcceleoDay:Program

fga@brian:~/tmp$ php5 test_array.php
With in_array :
111
time : 0.349022865295 sec
With isset on keys :
111
time : 0.000214099884033 sec
With array_key_exists :
111
time : 0.00021505355835 sec

Searching on keys is 1000 to 10000 times faster regarding the bench on an array containing 700 000 elements.

Here is the code of the test :

<?php
// array to store white list as values
$t = array();
// array to store white list as keys
$u = array();

// elements count
$max = 700000;

$first = $last = $middle = '';
for($i=$max-1;$i>=0;$i--){
        // values are random strings
        $id = uniqid(rand());
        $t[] = $id;
        $u[$id] = '';
        // we store first, last and middle values to
        // to search for them
        switch($i) {
                case $max-1:
                        $first = $id;
                break;
                case 0:
                        $last = $id;
                break;
                case $max/2:
                        $middle = $id;
                break;
        }
}

echo "With in_array :\n";
$start_time = microtime(true);
echo in_array($first,$t);
echo in_array($last,$t);
echo in_array($middle,$t);
echo "\n";
echo "time : " . (microtime(true)-$start_time) . " sec";
echo "\n";

echo "With isset on keys :\n";
$start_time = microtime(true);
echo isset($u[$first]);
echo isset($u[$last]);
echo isset($u[$middle]);
echo "\n";
echo "time : " . (microtime(true)-$start_time) . " sec";
echo "\n";

echo "With array_key_exists :\n";
$start_time = microtime(true);
echo array_key_exists($first,$u);
echo array_key_exists($last,$u);
echo array_key_exists($middle,$u);
echo "\n";
echo "time : " . (microtime(true)-$start_time) . " sec";
echo "\n";

See the bug at :  http://framework.zend.com/issues/browse/ZF-3392

In partial solutions, I’ve found a function which computes the real width of a string according to the font and the font size. By aggregating every chunks, I’ve made my getWrappedText() method which returns a string with the correct \n :

protected function getWrappedText($string, Zend_Pdf_Style $style,$max_width)
{
    $wrappedText = '' ;
    $lines = explode("\n",$string) ;
    foreach($lines as $line) {
         $words = explode(' ',$line) ;
         $word_count = count($words) ;
         $i = 0 ;
         $wrappedLine = '' ;
         while($i < $word_count)
         {
             /* if adding a new word isn't wider than $max_width,
             we add the word */
             if($this->widthForStringUsingFontSize($wrappedLine.' '.$words[$i]
                 ,$style->getFont()
                 , $style->getFontSize()) < $max_width) {
                 if(!empty($wrappedLine)) {
                     $wrappedLine .= ' ' ;
                 }
                 $wrappedLine .= $words[$i] ;
             } else {
                 $wrappedText .= $wrappedLine."\n" ;
                 $wrappedLine = $words[$i] ;
             }
             $i++ ;
         }
         $wrappedText .= $wrappedLine."\n" ;
     }
     return $wrappedText ;
}

/**
 * found here, not sure of the author :
 * http://devzone.zend.com/article/2525-Zend_Pdf-tutorial#comments-2535
 */
 protected function widthForStringUsingFontSize($string, $font, $fontSize)
 {
     $drawingString = iconv('UTF-8', 'UTF-16BE//IGNORE', $string);
     $characters = array();
     for ($i = 0; $i < strlen($drawingString); $i++) {
         $characters[] = (ord($drawingString[$i++]) << 8 ) | ord($drawingString[$i]);
     }
     $glyphs = $font->glyphNumbersForCharacters($characters);
     $widths = $font->widthsForGlyphs($glyphs);
     $stringWidth = (array_sum($widths) / $font->getUnitsPerEm()) * $fontSize;
     return $stringWidth;
 }

then you can draw the text easily :

$y = 700;
$lines = explode("\n",$this->getWrappedText($text,$style_text,400)) ;
foreach($lines as $line)
{
    $page2->drawText($line, 140, $y);
    $y-=15;
}

To achieve this, I’ve created a formSlider view helper which is then used by a slider form element.

The view helper and form element code is here. To allow ZF to find the helper, don’t forget to add path to helper in your bootstrap :

$layout->getView()->addHelperPath('Mc/View/Helper','Mc_View_Helper') ;

You need of course to include scriptaculous and prototype to make it work (available here and here) :

<script src="/prototype-1.6.0.2.js" type="text/javascript"></script>
<script src="/scriptaculous.js" type="text/javascript"></script>

Then, you can create a slider like this :

require_once('Mc/Form/Element/Slider.php') ;
$my_form->addElement(new Mc_Form_Element_Slider('my_element')
    ,'my_element') ;
$my_form->my_element->setLabel('My element : ')
    ->setMin(10)
    ->setMax(30)
    ->setStep(2);

and retrieve the value as usual :

$my_form->my_element->getValue() ;

And if you want to override the default style in your css, don’t forget the !important argument :

div.slider {
    width:256px !important;
    margin:10px 0 !important;
    background-color:lightgray !important;
    height:15px !important;
    position: relative !important;
 }

div.slider div.handle {
     width:10px !important;
     height:15px !important;
     background-color:darkgray !important;
     cursor:move !important;
     position: absolute !important;
 }

function autoresize(txtbox)
{
    var cols = txtbox.cols ;
    var content = txtbox.value ;
    var lineCount = 0 ;

    var lastEOL = -1 ;
    do {
        var begin = lastEOL+1 ;
        lastEOL = content.indexOf("\n",lastEOL+1) ;
        var line = "" ;
        if(lastEOL != -1) {
            line = content.substring(begin,lastEOL) ;
        } else {
            line = content.substring(begin,content.length) ;
        }
        var rows_in_line = Math.floor(line.length/cols)+1 ;
        lineCount += rows_in_line
    } while (lastEOL != -1) ;
    txtbox.rows = lineCount ;
}

and html code :

<textarea name="my_textbox" onkeyup="autoresize(this)"
onmouseup="autoresize(this)" rows="24" cols="80"></textarea>

mplayer -identify -frames 0 dvd://

To encode the 17 chapters of the first title of a dvd :

for i in $(seq 17) ; do mplayer -vo null -ao pcm -ao pcm:file=$i.wav:fast -chapter $i-$i dvd://01 ; flac $i.wav --best & done

The initial need is for my own server but it will also be useful for my company. The goal is to provide our best practice for vhost in a tool.

To manage ACL, I’ve also begun to generate an admin interface which is also for now quite simple (displaying a big table with all roles and resources). Concerning resources, I’ve define three layers : module, screen, action. I don’t know yet what is the best practice to apply ACL to a particular object. I will think of it during next weeks.

I’ve also added a block view helper which displays blocks in the layout if you are allowed to. A block is just a screen rendered as a menu, what minimize concepts in the model. There’s also a special block : the context. Thanks to a context action helper, each action can register contextual action which will then appear in the context menu. For instance, the “create” action will be able to set “edit” and “delete” action as contextual actions.

I’m busy this week, and I was this last two weeks (giving a ZF formation ) but I will switch form generation to Zend_Form as soon as possible. Despite my first opinion, which was against the use of Zend_Form, I find this component very useful and productive. Even if it’s bad to put view logic in the controller, it seems to be far easier to maintain.

I think the 0.3.0 release will happen soon including everything to build a blog example (and many other application). 0.4.0 will focus on cleaning up the code, polishing the interface, trying to improve ACL. I hope there won’t be a 0.5