D-talk

Multiple PHP versions on one webserver

nospam@example.com (Mark van der Velden) — Tue, 03 Nov 2009 08:39:00 +0100

Introduction

This is a blog about running two PHP versions on one webserver and using multiple php.ini files, this combination can be a tricky one to tackle. But luckily one we can tackle quite easily as long as one of the PHP versions is >= 5.2.7. For this example I'll be using Apache, but the webserver flavor doesn't really matter. The most important part is the "PHP_INI_SCAN_DIR" environment variable.

The why

There could be a number of reasons to want what I'm about to talk about. In my case I have a project where I have a legacy code-base, running on a specific PHP version, and a new code-base which will be run on 5.3. Because the new code-base will be a ongoing progress of replacing the old, it first has to run side by side with the legacy code-base. So I wanted my development image to run two PHP versions.

The old code-base used php.ini settings such as a include-path, error reporting, etc. Which will be different from the new code-bas, and those can no-longer be set with the 'php_value' feature of Apaches since the PHP version we'll be using for that runs as (f)CGI rather then as module.

Continue reading "Multiple PHP versions on one webserver"

Javascript printing a popup window

nospam@example.com (Mark van der Velden) — Thu, 29 Oct 2009 15:25:47 +0100

For the impatient, a working example:http://dynom.nl/jquery/print_popup.html

It seems so easy, but I had some trouble printing a popup window containing an image. Whenever I printed the page using the following code it failed.

/**
* FAIL
*/
function printIt() {
var win = window.open('/path/to/image.jpg', 'Image', 'resizable=yes,...');
if (win) {
win.focus();
win.print();
}

return false;
}

So I changed from opening a URL to writing a IMG tag to the opened window, which works like a charm.

/**
* Works like a charm.
*/
function printIt() {
var win = window.open('', 'Image', 'resizable=yes,...');
if (win) {
win.document.writeln('<img src="/path/to/image" alt="image">');
win.document.close();
win.focus();
win.print();
}

return false;
}

And to put it in jQuery terms:

/**
* To put it in jQuery terms:
*/
Popup = {

init : function () {
$('a#action_print').bind('click', Popup.printIt);
},

printIt : function () {
var win = window.open('', 'Image', 'resizable=yes,...');
if (win.document) {
win.document.writeln('<img src="'+ $(this).attr('href') +'" alt="image" />');
win.document.close();
win.focus();
win.print();
}

return false;
}
}

$(document).ready(function () {
Popup.init();
});

Multiple backend session storage handler

nospam@example.com (Mark van der Velden) — Sun, 11 Oct 2009 11:17:00 +0200

Recently I got asked if I knew about a system that supports multiple session back-ends at once. I didn't know about one and since it's not rocket-science I decided to spent a few hours and whoop something up.

For the impatient, checkout: http://github.com/Dynom/SessionHandler

What does it do?

It is a drop-in high-availability storage back-end for PHP sessions by offering a redundant session storage system. It's as easy as including the lib, define the drivers you want to use (e.g. Memcache and MySQL) prepare their configuration/installation and done. If you already have a MySQL server and a Memcache instance running you can set it up in about 5 minutes. It's also easy to extend and write new drivers, just extend the template class and fill in the blanks.

Continue reading "Multiple backend session storage handler"

Sorting of lists in jQuery

nospam@example.com (Mark van der Velden) — Tue, 06 Oct 2009 13:00:00 +0200

A while back I posted a simple sorting algorithm for number sorting, but it doesn't really do the trick for regular strings (e.g. anchors). But since I needed one recently I wrote another small and very simple sorting solution.

For a working example, see: http://dynom.nl/jquery/listsort.php

My.List = {
Sort : function (listSelector) {
var sortedElements, left, right;

// If we have any list items to sort on
if ($(listSelector + ' li').length > 0) {

// Remove the items from the DOM
sortedElements = $(listSelector + ' li').remove();

// Sort, using a custom sorting and compare by anchor contents
sortedElements.sort(function (a, b) {
left = $(a).children('a').html();
right = $(b).children('a').html();

if (left > right) {
return 1;
} else if (right < left) {
return -1;
} else {
return 0;
}
});

// Place the items back on the DOM
$(listSelector).append(sortedElements);
}
}
};

Again, the source should be self explanatory

Click many, call once with jQuery

nospam@example.com (Mark van der Velden) — Tue, 06 Oct 2009 12:28:00 +0200

Recently I wanted to improve they way some anchors where handled in my recent project, it works a bit like adding and removing items to/from a list. But it was possible to trick the interface by quickly clicking multiple times on a link before the AJAX request was finished, while the back-end handled this without any problems, the interface for the visitor couldn't. And since I'm a neat freak and I had a few minutes to spare, I came up with the following.

A working example: http://dynom.nl/jquery/clickmanycallonce.html.

My.items = {
init : function () {
// Bind the real item only once, and the dummy item permanently
// This way the *real* item is only called once, regardless of the amount of clicks
// And the link remains clickable but doesn't trigger the browser to follow it.
$('ul>li>a.item').one('click', My.items.real_action).bind('click', My.items.dummy_action);
},

dummy_action : function () {
$(this).html( $(this).html() + '.' );
return false;
},

real_action : function () {
/* Fancy AJAX call, that shouldn't be executed more then once for every click */
$('div#frame').html($('div#frame').html() + "<br>\nCalling 'real_action' for anchor: " + $(this).html());
return false;
}
};

// When the DOM is ready
$(document).ready(function () {

// Attach the filter to our input and list
My.items.init();

});

While the code is fairly self explanatory and quite simple here the steps in a bit more detail:

Unobtrusively binding, as soon as the DOM is ready.
Binding the real action handler on 'click' action with jQuery's 'one()' event handler
Binding the dummy action handler on 'click' action with the 'bind()' event handler

This situation is probably only favorable if the item you click is removed from the DOM (or has actions re-bound after the call) else it might not be what you want.

The PHP Quiz series

nospam@example.com (Mark van der Velden) — Fri, 25 Sep 2009 07:23:00 +0200

I like solving puzzles, probably one of the reason why I like programming as much as I do. I also like finding challenges and experimenting, as such I came to the idea to start the PHP Quiz series. They contain typical combination of PHP quirks and lesser known features of PHP.

The reason behind the quizzes is not to advocate bad or good coding practices, but it's intended to let you find out the why in all of it. I believe that by understanding what happens it can make you a better programmer and you might spot bugs easier then without knowing what happens.

The series are not ordered in level of difficulty but merely in the order that I found out about them, thought about them or where simply sent in. But in general I think it's safe to say that your knowledge of PHP should be quite a leap forward from novice before you can answer most questions. This however doesn't mean that, once you can do the quizzes flawlessly, that you are a superior programmer. There is a big different between knowing how to design an application and knowing why $array = array(1,1) + array(2,2) only results in an array with two elements.

An overview of all the PHP Quizzes: http://blog.dynom.nl/categories/PHPQuiz_12

A special thanks to the people who sent in code samples, happy quizzing!

-D

PHP Quiz part 3

nospam@example.com (Mark van der Velden) — Mon, 21 Sep 2009 17:35:00 +0200

Welcome to another part of the PHP Quiz series, again some interesting questions to crack your brain about. If you have some nice additions or questions, be sure to leave a comment. Enjoy part three!

As always, think of the answer before you execute the code or look it up. You can find round two here.

Unset cast

What is the type of $a and what is the type of $b

$a = "A";
$b = (unset) $a;
var_dump($a, $b);

Form fun

What will the output be?

Fun with strings

Strings in PHP are versatile, but how versatile are they... What will the output be?

$juggling = "Itffkhmf";
$rox = "Spy";
$b = $c = "";
for ($i=0; $i<strlen($juggling); $i++) {
$b .= $juggling[ $i ];
$b++;
}
for ($i=0; $i<strlen($rox); $i++) {
$c .= $rox[ $i ];
$c--;
}

var_dump( $b, $c );

Continue reading "PHP Quiz part 3"

New airfilters and map update

nospam@example.com (Mark van der Velden) — Sun, 30 Aug 2009 23:06:00 +0200

Last Saturday I went for new air filters and a new (injection) mapping. I was planning to get that done anyway, but then I decided to update my blade with two K&N filters also. Slightly more performance and little to no more maintenance needed in the future regarding that area. (And honestly, while the filters are much more accessible then at my previous bike. It's still not the most fun part to clean.) After approx. 2 hours they finished tuning and she took one more run on the Dynojet. A total of 165 bhp on the rear wheel and (the most valuable part) a much faster throttle response and better power outtake.

It was costly for something that seems minor, but as soon as I drove off and noticed the difference it was all worth it!

The way a developer community works

nospam@example.com (Mark van der Velden) — Wed, 05 Aug 2009 13:00:00 +0200

I was watching the talk "Standing out in the crowd" by speaker Kirrily Robert at OSCON 09. And tweeted about this (http://twitter.com/Dynom/statuses/3142970947/) and when I read it back it got me thinking. And I decided to blog about it.

Much of what Skud (Kirrily) says is without a doubt true, but doesn't apply sole to women. It's generally the way it "works" in the open source world and between developers in general. There is a certain attitude that is simply there, not just between language fanbois but also between developers in general. Your sexual orientation, sex, hair color or religion has nothing to do with that. Partially I think the attitude is there to improve yourself, at least that's how it works for me. You try to be as good as the one you think is better then you are.

In a lot of communities, you don't explicitly mention your gender. You simply join a community (subscribe to a form or e-mail list) and you start posting/reading etc. And unless your nick is 'Girlygirl99' it's not too obvious in name also, so I wonder how people treat anyone based on their online identity. Feel free to prove me wrong on that, it's not that I don't believe it, I simply have never seen discrimination towards sex or sexual orientation in any community I've been in.

And maybe it differs a lot per community, I'm involved in the PHP community and from what I hear it has a small percentage PHP developers that are female, and they even have their own "support site" PHPWomen.org. And they seem to do pretty well.

As Skud quotes in her talk, some projects have a "diversity statement". I think it's nonsense to mention it at any community/project. It should only be mentioned if it doesn't say "everyone". If you want to be part of a community, simply step in. Order a beer, listen and join the conversation. If you lack the assertive skills to do that, it's not something the community can do about. It's something you need to improve on. If a community helps beginners, well that is a (big) plus.

Personally I don't care what you are, as long as you aren't (secretly) part of Skynet.

Comments are more then welcome.

Taking her for a dyno run

nospam@example.com (Mark van der Velden) — Sun, 12 Jul 2009 14:29:34 +0200

Yesterday I took my new bike for a spin on a Dynojet. I did this for a number of reasons, since I didn't bought the bike from a dealer I didn't know for sure if the bike was in perfect shape, and also I wanted to know how much *real* BHP it has, since the bike is slightly tuned (Power commander and Termignoni exhaust), which is definitely not stock.

The score was excellent, according to the readout my blade has 161BHP on the wheel (which is proximately 10% less then on the crankshaft, which is mostly used to indicate the power) and performs really nice, the graph shows a near linear output of power, no dips anywhere along the way which is simply near ideal. However there is some misconfiguration between 4k-6k rpm, the fuel maps are not rich enough, which is something that needs correcting! So I'll make an appointment for a followup meeting with the tune company to create a custom map for my bike.

A new love, black beauty

nospam@example.com (Mark van der Velden) — Sat, 04 Jul 2009 13:37:00 +0200

Ever since Honda announced the 2007 1000rr model, better known as the "Fireblade", I fell in love with it. The black color set, the black suspension, the seat pipe exhaust, the aggressive looks and the power makes it a perfect bike. I recently had the possibilities to buy one and after searching for the right bike for about a year, I finally found it. Or, rather: found her!

A few statistics for a stock blade
Stock BHP/PK	158.8 (crankshaft)
Stock Weight (wet)	205Kg
Max RPM	12.200 rpm

Did you know... part two

nospam@example.com (Mark van der Velden) — Thu, 25 Jun 2009 19:14:00 +0200

In these blog series I'd like to talk a bit about some "Did you knows". These series contain information I came across along the way and I mention them here to give you insight or just to make you aware of it's existence. The information is by no means in chronological order and mostly not even covering "state of the art" or "brand new" items for that matter. Some are directly code related, others are just brief descriptions. Basically it's just a pile of PHP and web related information. You can find part one here.

Continue reading "Did you know... part two"

Apache's fail with 'encoded slashes'

nospam@example.com (Mark van der Velden) — Thu, 25 Jun 2009 14:58:45 +0200

Honestly it took me a while to debug a vague bug I had, at first I ignored it and used different path values, figuring it was a bad rewrite rule. I'm using a project and I'm developing on both Apache and IIS, with the one inconsistency that I always got a 404 when the path contained a encoded /, namely "%2F". So basically, a URL like this: http://domain.com/show/article/104671-Situation%20details%20n%2Fa (Title being: "Situation details n/a") is giving a 404. The error log was helpful, because it said:

[..] [info] [client 127.0.0.1] found %2f (encoded '/') in URI (decoded='//'), returning 404

Luckily, fixing this ~~bug~~ feature is easy. Add the following to your httpd.conf (vhost or server directive) and voila:

AllowEncodedSlashes On

Arguably you could be saying that %2F's simply shouldn't be in the path, but rather in the POST body or as GET parameter. However in a world where everything has to be SEO and url's have to be pretty, isn't this silly default behavior ? Especially since the RFC's also clearly state that an encoded forward slash (%2F) should not be treated as a regular '/'. To quote RFC 2616

Characters other than those in the "reserved" and "unsafe" sets (see RFC 2396 [42]) are equivalent to their ""%" HEX HEX" encoding.

and RFC 2396

2.2. Reserved Characters

   Many URI include components consisting of or delimited by, certain
   special characters.  These characters are called "reserved", since
   their usage within the URI component is limited to their reserved
   purpose.  If the data for a URI component would conflict with the
   reserved purpose, then the conflicting data must be escaped before
   forming the URI.

      reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
                    "$" | ","

jQuery simple unordered list filter

nospam@example.com (Mark van der Velden) — Wed, 24 Jun 2009 15:50:21 +0200

I needed a simple filter system on a unordered list. The goal is to filter 'realtime' based on what a user is typing. I came up with the following, if you have any suggestions and/or performance tips feel free to drop a line!

The HTML:

The blog software is messing with the HTML, for a working example with ungarbled code. Look at the bottom of this post.

</p><div>
<input name="filter" id="search_filter" type="text">
</div><div id="titles">
<ul>
<li><a href="http://blog.dynom.nl/path/to/item/1">Item 1</a></li>
<li><a href="http://blog.dynom.nl/path/to/item/2">Item 2</a></li>
<li><a href="http://blog.dynom.nl/path/to/item/3">Item 3</a></li>
</ul>
</div>

The Javascript

Working example

Visit http://dynom.nl/jquery/list.php for a working example.

Javascript cookie helper class

nospam@example.com (Mark van der Velden) — Tue, 26 May 2009 12:00:10 +0200

Little original perhaps, but I thought I'd share this cookie class. It makes my life a little easier,

My.Cookie = {

/**
   * Set a cookie
   * @param {string} n name
   * @param {scalar} v value
   * @param {int} days
   */
set: function (n, v, days) {
var e = '', d;
if (days) {
d = new Date();
d.setTime(d.getTime() + (days * 86400000));
e = "; expires=" + d.toGMTString();
}
document.cookie = n + "=" + v + e + "; path=/";
},

/**
   * get a cookie
   * @param {string} n name
   */
get: function (n) {
var match = n + "=", c = '', ca = document.cookie.split(';'), i;
for (i = 0; i < ca.length, c=ca[i]; i++) {
if (c.indexOf(match) === 0) {
return c.substring(match.length, c.length);
}
}

return null;
},

/**
   * Delete a cookie
   * @param {string} n name
   */
del: function (n) {
this.set(n, "", -1);
}
};