tutorial

Auto-mount Samba Share on Ubuntu and Windows

Submitted by Thirtysixway on Wed, 04/08/2009 - 5:09pm

SambaSamba is a very popular program used to share files, folders, and printers throughout networks with different computers and operating systems.  It's useful if you want to store or share things from one computer, say on an Ubuntu file server, and then access them from around the network, say on a Windows desktop or Ubuntu desktop. Read more about Auto-mount Samba Share on Ubuntu and Windows

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Automate Ubuntu Server Shutdown

Submitted by Thirtysixway on Mon, 02/09/2009 - 6:03pm

power downSomebody on the Ubuntu Forums was asking how to get their server to shut down automatically when no other computers are online on the network.  This can be useful if you have Wake-On-Lan enabled on the server, and you're only using it for things like printer or file sharing.  I responded with a little php script I whipped up that does the job nicely.

You will need the php package and the nmap package to make this work

sudo apt-get install php nmap

Next, you'll need to know how to setup a cron job.  If you don't, check out this tutorial.

Here is the contents of the php file.
hostsup.php
 

<?php
// Call the nmap command
$output = shell_exec('nmap -sP 192.168.1.*');

// Split up the output so we get the number of hosts up
$split1 = explode("addresses (", $output);
$split2 = explode(" hosts up", $split1[1]);
$hostsup = $split2[0];

// If only x number of computer are on + router, shutdown.  Take in account the server being a computer!
if($hostsup == "2") {
    $shutdown = shell_exec('shutdown -h now');
}
?>

You'll need to edit the "192.168.1.*" to fit your network's IP range.  Also, change the $hostsup == "2" to the number of computers you want on when it shuts down.  The server counts as one, your router counts as one, and if you have any of those network printers, they also count.  If it gets an IP, count it.  Feel free to change the shutdown command to something else if you want to put the server into standby or what have you.

In your cron job, just set the command as

php -f /path/to/file/hostsup.php

Set the cron to run as often as you like.  I'd set it for every half-hour just to not use up too many resources, and still be effective.

What this script is doing is executing "nmap -sP 192.168.1.*".  This generates a list of nodes on the network that are currently online, and their IP addresses.  The next 3 lines parse through the information to only get the number of nodes online.  Next we check how many are online, if the numbers match then execute the shutdown command.  You'll need root or sudo access to use the shutdown command, so watch out. Read more about Automate Ubuntu Server Shutdown

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Javascript and CSS aggregator/compressor

Submitted by Thirtysixway on Thu, 02/05/2009 - 6:10pm

clampI used an existing php class from http://joliclic.free.fr/php/javascript-packer/en/
Should work on both php4 and php5
(if using php4, just replace class.JavaScriptPacker.php with class.JavaScriptPacker.php4)

This is setup for the following-

/
/inc/
/inc/class.JavaScriptPacker.php
/js/
/js/cache/
/js/main.js
/js/tooltip.js
/js/js.php
/css/
/css/cache
/css/main.css
/ibox/skins/darkbox/darkbox.css

Make sure that /js/cache/ and /css/cache/ are writeable (chmod 777 for most people)

Here is /js/js.php

/js/js.php

 

<?php
ob_start();
require '../inc/class.JavaScriptPacker.php';

/********************************************
Edit the array below to add javascript files, relative to the location of this file.
*/
$arFiles = array(
        "main.js",
        "tooltip.js",
        );
/********************************************/
function compressJavascript($file) {
    $script = file_get_contents($file);
    $packer_php = new JavaScriptPacker($script, "Normal", true, false);
    $output = $packer_php->pack();
    
    return $output;
}
$output = "";

for($i = 0; $i < count($arFiles); $i++) {
    $devcontent = file_get_contents($arFiles[$i]);
    
    if(file_exists("cache/" . md5($arFiles[$i]) . ".cache")) {
        //file exists.
        $content = file_get_contents("cache/" . md5($arFiles[$i]) . ".cache");
        $split = explode("#",$content,2);

        if($split[0] == md5($devcontent)) {
            //file was not modified according to md5
            $output = $output . $split[1];
        }else{
            //file was modified according to md5, so update it.
            $newcontent = compressJavascript($arFiles[$i]);
            $create = file_put_contents("cache/" . md5($arFiles[$i]) . ".cache", md5($devcontent) . "#" . $newcontent);
            $output = $output . $newcontent;
        }
    }else{
        //file doesn't exist.
        $newcontent = compressJavascript($arFiles[$i]);
        $create = file_put_contents("cache/" . md5($arFiles[$i]) . ".cache", md5($devcontent) . "#" . $newcontent);
        $output = $output . $newcontent;
    }
    
}
header("Content-Type: application/javascript");
echo $output;
?>

Then here's /css/css.php

/css/css.php

 

<?php
ob_start();
require '../inc/class.JavaScriptPacker.php';

/********************************************
Edit the array below to add css files, relative to the location of this file.
*/
$arFiles = array(
        "main.css",
        "../ibox/skins/darkbox/darkbox.css",
        );
/********************************************/
function compressCSS($file) {
    $script = file_get_contents($file);
    $packer_css = new JavaScriptPacker($script, 'None', true, false);
    $output = $packer_css->pack();
    
    return $output;
}
$output = "";

for($i = 0; $i < count($arFiles); $i++) {
    $devcontent = file_get_contents($arFiles[$i]);
    
    if(file_exists("cache/" . md5($arFiles[$i]) . ".cache")) {
    
        //file exists.
        $content = file_get_contents("cache/" . md5($arFiles[$i]) . ".cache");
        $split = explode("#",$content,2);

        if($split[0] == md5($devcontent)) {
            //file was not modified according to md5
            $output = $output . $split[1];
        }else{
            //file was modified according to md5, so update it.
            $newcontent = compressCSS($arFiles[$i]);
            $create = file_put_contents("cache/" . md5($arFiles[$i]) . ".cache", md5($devcontent) . "#" . $newcontent);
            $output = $output . $newcontent;
        }
    }else{
        //file doesn't exist.
        $newcontent = compressCSS($arFiles[$i]);
        $create = file_put_contents("cache/" . md5($arFiles[$i]) . ".cache", md5($devcontent) . "#" . $newcontent);
        $output = $output . $newcontent;
    }
    
}
header("Content-Type: text/css");
echo $output;
?>

 

What the packer does is strip comments, remove whitespace, and (for the javascript one) it will create shorter variables, and encode it. This is useful because it will save bandwidth and make it a little more challenging for people to take your code or figure out your system.

The js.php and css.php use different compression types. Javascript uses "normal" because this will create shorter variables and whatnot. CSS uses "none" so that only comments and whitespace are removed. If you use "normal" on CSS you'll end up with javascript instead of css code.

So instead of using a <script> or <style> tags for each of your js/css files, you can use two to include js.php and css.php files (or even use PHP to include them in your file, removing any extra http requests.) Then edit the arrays in js.php and css.php to add files. They are all compressed into one page which will cut down on page requests as well as bandwidth.

The advantage of using this is so that you can develop in plain, readable text but still compress or hide your code to users without doing any extra steps. The updated code will create cached versions of the compressed files. Then using md5, compare the 2 copies. If the md5 is different, then it will update the cache.

It's not intended for sites under development. It's almost impossible to debug your javascript if it's compressed/encoded so I'd recommend only using this on a production version of your web site. Read more about Javascript and CSS aggregator/compressor

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DIY Verizon Ringtones

Submitted by Thirtysixway on Tue, 01/20/2009 - 10:54pm

Verizon WirelessFor those of you using cell phones, one of the more costly features is the ability to download custom ringtones.  Some ringtones on Verizon Wireless can cost $8.00.  That's almost half the price of a standard CD for a 30 second clip of one song.

Some carriers and phones let you choose an mp3 from your music player to use as a ringtone.  Others are open enough to let you go online and (for a price usually) find a ringtone and get it sent to your phone.  However, on Verizon Wireless you seem to be stuck.  You either buy a ringtone through Verizon's Get It Now feature or you wait for a Free download to show up in Get It Now which rarely ever happens.

With some tinkering and exploration online and on other web sites, I've found a way to get your favorite ringtones onto your Verizon phone for free and using any operating system.  You'll need the following:

  1. Your favorite mp3 file
  2. Audacity sound editor.  You will also need to make sure you have the LAME MP3 Encoder so that you can export as an mp3 file.
  3. An E-mail address
  4. Pix messaging.  If you don't have a texting plan, be careful as Verizon may charge you for downloading a text/pix message.

The first step is to open up your mp3 file in Audacity.  Select about 30 seconds worth of the song that you want to use as your ringtone.  Some phones support longer, but it keeps the file size down and therefore makes it faster to send. Also Verizon may reject your message if it's too large.

You can go up to Edit > Trim and this will crop your 30 seconds of music.  Now go to File > Export and save your file as an MP3 file.  The trick is to save it so that the file is an MP3, but its file extention is .midi.  So tack on .midi onto the end of the file name.

save file

save file with a .midi extention

are you sure

Select yes in this dialog box

So what we have so far is a 30 second clip of a song saved as a mp3 file with a .midi file extention.  Simple right?

Next, open up your email client.  For the TO address, your email will be (tendigitnumber) @vzwpix.com.  Example would be 5551230987@vzwpix.com.   You need to make sure that you fill in a subject, so make it something like "ringtone" and fill in something for the body so make it something like "ringtone".

Attach your .midi mp3 file you made earlier, and send the email.

email attachment

Make sure you fill in both a subject and body for the email!

You should get a pix message on your cell phone.  After you open it, go to options and select Save as Ringtone.

You may need to play around with the settings on Audacity to get the best sounding ringtone.  I'd suggest having it on mono instead of stereo, or raising the bitrate at which it encodes your mp3 file.

If you need help with anything, or you have any recommended settings post a comment or contact me.

Update:
This will not charge you for "data transfer" which can be expensive.  This will only charge on your bill as a Pix-Flix message.  If you have texting on your plan, you will not be charged at all.  If you don't have a texting plan, it will only cost about 25 cents for receiving a pix-flix message.

Doesn't charge data! Read more about DIY Verizon Ringtones

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