Think Blue

 

Code Tags: PHP
So I may be a bit late to the party, but I have now created by first GitHub project. For my project I decided to actually finish my MQTT class.

I have posted it at http://github.com/bluerhinos/phpMQTT

At the moment the publishing part works a treat, but there currently a problem with the subscribe part (hangs after about 3 hours) I am trying to trace the fault. Also at the moment it will only support quality of service (qos) of 0.

Example Publishing:

php code:
require("../phpMQTT.php");
$mqtt = new phpMQTT();
/* broker(broker address, broker port, client id); */
$mqtt->broker("example.com", 1883, "PHP MQTT Client");
$mqtt->connect();
/* publish( topic, message, qos); */
$mqtt->publish("bluerhinos/phpMQTT/examples/publishtest","Hello World!",0);
$mqtt->close();

Code Tags: bash
I needed to keep my GeoIP db up to date for my stats package so I decided to write a cron script that would do it for me.

bash code:
#!/bin/bash
 
#############################################################
# ./geoipupdate = Auto updates the free GeoIP databases
# (c) andrew[at]bluerhinos.co.uk 2010 : Creative Commons
#############################################################
 
#list of urls
URLS=" http://geolite.maxmind.com/download/geoip/database/GeoLiteCountry/GeoIP.dat.gz"
URLS="$URLS http://geolite.maxmind.com/download/geoip/database/GeoLiteCity.dat.gz"
 
#target directory
TARGETDIR="/var/lib/GeoIP"
 
for URL in $URLS
do
        wget -q -N -P "$TARGETDIR" "$URL"
        BASENAME=`basename "$URL"`
        gunzip -f  "$TARGETDIR/$BASENAME";
done
 

Place the above code (or download here http://blogs.bluerhinos.co.uk/data/files/9/geoipupdate ) into /etc/cron.monthly/geoipupdate

Note: they update their db on the 1st or 2nd so I changed my /etc/crontab so that the monthly scrips run on the 3rd

If you are like me, you dislike the .php extension for web pages that display content, eg /contactus.php . To me this is a web page that is displaying HTML, so lets give it an .html suffix. but the easist way to implements templates is to use html.

To achieve this easily just create a .htaccess file to redirect .html's to .php.

.htaccess code:
 
RewriteEngine On
RewriteRule (.*).html $1.php [QSA]
 

(The QSA just forwards all variables to the .php script)
Requirements: are apache and mod_rewrite
More Info: http://www.kuro5hin.org/story/2003/7/31/2335/08552

Code Tags: PHP
I was working on a project that needed to list the Beaufort wind force. The first attempt was to do a lookup based function using the data here: http://en.wikipedia.org/wiki/Beaufort_scale

Attempt 1

php code:
function beaufort_scale($speed, $unit="m/s"){
 
    $units['m/s'] = 1;
    $units['kph'] = 1/3.6;
    $units['mph'] = 0.44704;
    $units['kts'] = 0.514444444;
 
    if(!in_array($unit,array_keys($units))){
        return "Error: couldn't recognise unit";
    }
 
    $speed *= $units[$unit];
 
    $scale = array(0.3,1.5,3.4,5.4,7.9,10.7,13.8,17.1,20.7,24.4,28.4,32.6,1000);
 
    foreach($scale as $key=>$val){
        if($speed <= $val) return $key;
    }
    return 'Error';
}

I then noticed on the wikipedia page the scale's empirical formula
so i thought i could improve the function ;)

v = 0.866 * B^3/2 (units m/s)

Attempt 2

php code:
function beaufort_scale($speed, $unit="m/s", $rnd=0){
 
   $units['m/s'] = 1;
   $units['kph'] = 1/3.6;
   $units['mph'] = 0.44704;
   $units['kts'] = 0.514444444;
 
   if(!in_array($unit,array_keys($units))){
      return "Error: couldn't recognise unit";
   }
 
   $speed *= $units[$unit];
 
   $scale = pow(($speed/0.836),(2/3));
 
   return round($scale,$rnd);
}

This one has the added ability of returning a decimal answer

Os: Debian
Oh and it has to be stable ish.

Yesterday I had to try and get php-ffmpeg and x264 enabled ffmpeg to sit side by side each other on a Debian Lenny install. The problem is that debian's ffmpeg that ships in the lenny package tree is not 264 enabled. But when you use the ffmpeg from debian-multimedia it breaks the installed php-ffmpeg.

So I suggest you do this:

Start With vanilla debian install

Install your php, apache, php-ffmpeg etc

Then add your debian-multimedia.org as a apt source.

Then follow these instructions
http://tovid.wikia.com/wiki/Installing_svn_ffmpeg_on_a_Debian_based_distro
(I have attahed a pdf of the page incase its not there when you read this, Data: Instruction for compiling ffmpeg

Happy Hunting