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Free Software / Open Source Business Models

Saeid Zebardast — Sun, 23 Oct 2011 18:18:07 +0000

The 2nd Technical Conference of The Free Software / Open Source held on Sep 8-9, 2011 in Zanjan, Iran. I had a conference about Free Software and Open Source Business Models. I’ve uploaded my presentation on slideshare.net. I hope this help newbies to understand Open Source business models.

Free Software / Open Source Business Models

• Download Free Software / Open Source Business Models (PDF, 2.3 MB)

About Saeid Zebardast

I'm Senior software engineer with 5+ years of professional experience includes cross-platform proficiency with considerable knowledge of programming languages especially Java and programming paradigms such as OO and development methodologies. Also I'm MySQL DBA since 2006.

How to find IP locations using MySQL

Saeid Zebardast — Mon, 14 Mar 2011 15:18:59 +0000

Introduction
Here we learn how to use MySQL for locating an IP address. At first we create a table that contains the name of the country and its IP address range. Then define a function to find country name of IP Address.

What’s Ip Address?

Quoting from the “IP address” page in Wikipedia:

An Internet Protocol address (IP address) is a usually numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: “A name indicates what we seek. An address indicates where it is. A route indicates how to get there.”

Table (database)
I created the ip_location table to save countries and IP Address ranges. Enter the following command:

CREATE TABLE `ip_location` (
  `from_ip` int(15) DEFAULT NULL,
  `to_ip` int(15) DEFAULT NULL,
  `country` varchar(32) DEFAULT NULL,
  KEY `from_ip` (`from_ip`,`country`),
  KEY `to_ip` (`to_ip`,`country`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC;

Then you need to import ip_location data. I exported my table with data via mysqldump. You should download it and use mysql command to restore it.
• Download ip_location.sql.zip (165KB)

getIpCountry() function
Now you need to create the function to extract country name:

DELIMITER $$
CREATE FUNCTION getIpCountry(ip varchar(15)) RETURNS varchar(64)
BEGIN
 declare a tinyint unsigned;
 declare b tinyint unsigned;
 declare c tinyint unsigned;
 declare d tinyint unsigned;
 declare total bigint;
 declare result varchar(64);
 select substring_index(ip, '.', 1 ) into a;
 select substring_index(substring_index(ip , '.', 2 ),'.',-1) into b;
 select substring_index(substring_index(ip , '.', -2 ),'.',1) into c;
 select substring_index(ip, '.', -1 ) into d;
 set total := (a*256*256*256) + (b*256*256) + (c*256) + d;
 select SQL_CACHE country into result from ip_location where total between from_ip and to_ip limit 1;
 if (result is null) or (result = '') then
 set result := 'unknown';
 end if;
 return result;
 END$$
DELIMITER ;

And done! You just need to use select command in MySQL cli:

mysql> SELECT getIpCountry('79.175.165.171');
+--------------------------------+
| getIpCountry('79.175.165.171') |
+--------------------------------+
| IRAN (ISLAMIC REPUBLIC OF)     |
+--------------------------------+
1 row in set (0.03 sec)

mysql> SELECT getIpCountry('4.2.2.4');
+-------------------------+
| getIpCountry('4.2.2.4') |
+-------------------------+
| UNITED STATES           |
+-------------------------+
1 row in set (0.00 sec)

Let me know if you have other way

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How to get pure content from HTML page in Java via Regex

Saeid Zebardast — Wed, 19 Jan 2011 14:19:00 +0000

Introduction
I’ve written a web crawler while I was developing a search engine a few weeks ago. It extracts the contents and saves them onto the database. The HTML tags aren’t so important to most of the search engines. So, I removed them successfully. To do the same, follow below steps:
1- Remove the script tags and inclusive content:

// htmlContent is full content of page with HTML codes.

String content;
Pattern pattern;

pattern = Pattern.compile(".*?", Pattern.DOTALL | Pattern.CASE_INSENSITIVE);
content = pattern.matcher(htmlContent).replaceAll("");

Note: In dotall mode, the expression . matches any character, including a line terminator. By default this expression does not match line terminators.

2- Remove the style tags and inclusive content:

String content;
Pattern pattern;

pattern = Pattern.compile(".*?", Pattern.DOTALL | Pattern.CASE_INSENSITIVE);
content = pattern.matcher(content).replaceAll("");

3- Remove all HTML tags without inclusive content.

pattern = Pattern.compile("<[^>]*>");
content = pattern.matcher(content).replaceAll("");

4- Replace new lines, tabs and multiple spaces with a single space.

content = content.replaceAll("\n+", " ");
content = content.replaceAll("\t+", " ");
content = content.replaceAll("(  )+", "");

And you have a pure content now

Links
Regular expression
How to Write an HTML Parser in Java
Regular-Expressions.info

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Java: run command as root by Runtime.getRuntime().exec() in Ubuntu

Saeid Zebardast — Mon, 06 Dec 2010 07:53:33 +0000

Hey

a few days ago I needed to run `/etc/init.d/networking restart` command by Runtime.getRuntime().exec() in Java EE web application. The first and easiest way that came to mind was sudo without password and… It Worked!
* To execute sudo without password, open /etc/sudoers by text editor like `nano`:

$ sudo nano /etc/sudoers

And add your user or group to the end of file like below:

# for user
USER_NAME ALL= NOPASSWD: ALL

# for group
%GROUP_NAME ALL= NOPASSWD: ALL

let’s see my Java code:

String command = "sudo /etc/init.d/networking restart";
Runtime runtime = Runtime.getRuntime();
try {
    Process process = runtime.exec(command);
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
    String line;
    while ((line = bufferedReader.readLine()) != null) {
        System.out.println(line);
    }
} catch (IOException e) {
    e.printStackTrace();
}

Troubleshooting
if you get `sudo: no tty present and no askpass program specified` error, make sure the user that runs command is in /etc/sudoers.

let me know if you find similar or easier way

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/etc/network/interfaces configuration for 802.1x authentication

Saeid Zebardast — Tue, 02 Nov 2010 06:14:08 +0000

Hey

I have a problem with adjust Network Manager for 802.x1 Tunneled TLS (TTLS) and MD5 in Ubuntu. MD5 does not exist in `Inner Authentication` when I choose TTLS.
I was forced to enter the settings to interfaces file (/etc/network/interfaces). Interfaces file content is shown below:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address xx.xx.xx.xx
netmask xx.xx.xx.xx
gateway xx.xx.xx.xx
wpa-driver wired
wpa-eap TTLS MD5
wpa-key-mgmt IEEE8021X
wpa-anonymous-identity USER_NAME
wpa-identity USER_NAME
wpa-password PASSWORD
wpa-phase1 auth=MD5
wpa-phase2 auth=PAP password=PASSWORD

Also you can use Open1X (XSupplicant).

Links
• IEEE 802.1X
• Network 802.1x Authentication
• Open1X (XSupplicant)

Have a good time

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TV show “SefroYek”: “Open Source operating systems”

Saeid Zebardast — Thu, 23 Sep 2010 08:50:44 +0000

Hey,

A few days ago, I was invited to “SefroYek” a technical TV show that discusses with experts. That was second session and I’ve been there to talk about “Open Source operation systems”. I opened the discussion with GNU/Linux. Next, I answered the questions. There were many questions about equivalent windows softwares in GNU/Linux. I uploaded the first part. It’s in Persian language.

Open Source operating software from Saeid Zebardast on Vimeo.

I’ve wrote more information about this TV show in my Persian blog.

Have a good time

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Fetch full posts content of FeedWordPress feeds

Saeid Zebardast — Mon, 05 Jul 2010 03:57:59 +0000

I use WordPress and FeedWordPress plugin to create a planet. It’s great plugin. Some bloggers don’t show full post content on their feeds. If you like to get the full content of posts, you can contact to blogger and ask his/her to enable full content on the feed or continue to read this article.
I create functions to get full content of posts.

Requirement

PHP with cURL support (Client URL Library)
Permissions to modify theme files
Text editor
basic php programming skills

Step 1 – Where is post content?
It’s easy. just open the web page and see the page source.
For example, open http://zebardast.ir/en/linux-and-unix-bash-shell-aliases/ (Single post with full content) and see the page source.
On the page source you can see the content which is started by below code:

and ended by :

* It’s not ended only by because there is some divs on post content. So I add some html code after which is unique.

Step 2 – Add started and ended code to `Custom Feed Settings`
Open the wordpress administration panel and go to the `Feed and Update Settings` page. Select the feed from drop down menu (Here `Saeid Zebardast’s Blog`).
Add started and ended code to `Custom Feed Settings`:

— Add started and ended code to `Custom Feed Settings`

Step 3 – Fetch full content from source and update post on wordpress
Open functions.php in text editor and add the below codes to the end of it:

 true,     // return web page
        CURLOPT_HEADER         => false,    // don't return headers
        CURLOPT_FOLLOWLOCATION => false,     // follow redirects
        CURLOPT_ENCODING       => "",       // handle all encodings
        CURLOPT_USERAGENT      => "ayy.ir spider", // who am i
        CURLOPT_AUTOREFERER    => true,     // set referer on redirect
        CURLOPT_CONNECTTIMEOUT => 120,      // timeout on connect
        CURLOPT_TIMEOUT        => 120,      // timeout on response
        CURLOPT_MAXREDIRS      => 10,       // stop after 10 redirects
    );

    $ch      = curl_init( $url );
    curl_setopt_array( $ch, $options );
    $content = curl_exec( $ch );
    $err     = curl_errno( $ch );
    $errmsg  = curl_error( $ch );
    $header  = curl_getinfo( $ch );
    curl_close( $ch );

    $header['errno']   = $err;
    $header['errmsg']  = $errmsg;
    $header['content'] = $content;
    return $header;
}

function before ($this, $inthat)
{
    return substr($inthat, 0, strpos($inthat, $this));
}; 

function after ($this, $inthat)
{
    if (!is_bool(strpos($inthat, $this)))
    return substr($inthat, strpos($inthat,$this)+strlen($this));
}; 

function multi_between($this, $that, $inthat)
{
   $counter = 0;
   while ($inthat)
   {
      $counter++;
      $elements[$counter] = before($that, $inthat);
      $elements[$counter] = after($this, $elements[$counter]);
      $inthat = after($that, $inthat);
   }
   return $elements;
} 

function strbet($inputStr, $delimeterLeft, $delimeterRight, $debug=false) {
    $posLeft=strpos($inputStr, $delimeterLeft);

    if ( $debug ) {
    	echo $posLeft;
    }

    if ( $posLeft===false ) {
        if ( $debug ) {
            echo "Warning: left delimiter '{$delimeterLeft}' not found";
        }
        return false;
    }
    $posLeft+=strlen($delimeterLeft);
    $posRight=strpos($inputStr, $delimeterRight, $posLeft);
    if ( $posRight===false ) {
        if ( $debug ) {
            echo "Warning: right delimiter '{$delimeterRight}' not found";
        }
        return false;
    }

    if ( $debug ) {
    	echo $posLeft;
    	echo $posRight;
    }

    return substr($inputStr, $posLeft, $posRight-$posLeft);
} 

?>

Close functions.php and open single.php in text editor. Add the below codes after ``:

After it, replace `the_content()` with:

 echo $my_content;

Close text editor and Upload functions.php and single.php to your theme folder. Now go to the single post and see the full content.
Just try it!

External links
• WordPress
• FeedWordPress (Homepage)
• FeedWordPress (WordPress plugin directory)
• Client URL Library

Good luck

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Installing Sun JDK 5 on Ubuntu 9.10 and 10.04

Saeid Zebardast — Mon, 03 May 2010 02:21:19 +0000

Hello

As you known, Sun JDK version 1.5 or 5 is deleted from Ubuntu 10.4 and 9.10 repositories and the version 6 has been replaced.

The easiest way to install Sun JDK 5 version is add its repository from Ubuntu 9.04 to the list of repositories in 9.10 and 10.04. For this purpose, follow the steps.

1- Open /etc/apt/sources.list with a text editor like gedit:

sudo gedit /etc/apt/sources.list

2- Add the following lines to the end of the file then save it and close:

  ## For sun-java5-jdk
 deb http://ir.archive.ubuntu.com/ubuntu jaunty-updates main multiverse

3- Update the packages lists and install sun-java5-jdk:

 sudo aptitude update
 sudo aptitude install sun-java5-jdk

* Above method can be used for other applications.

Another way to install jdk 5 is download software package and its dependencies from packages.ubuntu.com.

Good luck

About Saeid Zebardast

How to find hardware information from command line on Linux

Saeid Zebardast — Mon, 01 Mar 2010 14:25:26 +0000

— linux

In this post you can see some useful command to find and show hardware information on Linux.

Default commands

ALL devices

dmesg

dmesg will show you the kernel messages which can show you all the devices the kernel has found (hard disks,cdroms,etc)

CPU

# cat /proc/cpuinfo

Memory

# cat /proc/meminfo
$ free

PCI (including usb bridges,agp cards etc)

$ lspci

USB devices (mice,etc)

$ lsusb

Hard drives

# fdisk -l
$ df -h

Additional Command

lshw

lshw is a Linux command which provides details of all the hardware in your PC. The details provided by the lshw command run the gamut of processors, memory, slots, onboard sound, video chipset and more.

Install lshw

Arch:

# pacman -S lshw

Debain, Ubuntu or any of its derivatives:

$ sudo aptitude install lshw

Redhat, fedora, CentOS:

# yum install lshw

Gentoo:

# emerge lshw

Run lshw

# lshw
# lshw -short

To get the output in HTML, you use the -html option as follows:

# lshw -html > hardware-info.html

• See lshw command – List hardware information in Linux

dmidecode

dmidecode command reads the system DMI table to display hardware and BIOS information of the server. Apart from getting current configuration of the system, you can also get information about maximum supported configuration of the system using dmidecode. For example, dmidecode gives both the current RAM on the system and the maximum RAM supported by the system.
dmidecode is installed by default on many linux distribution like debain, ubuntu and fedora.
• See How To Get Hardware Information On Linux Using dmidecode Command

have a good time

About Saeid Zebardast

Synchronizing Google Tools with Kontact

Saeid Zebardast — Mon, 16 Nov 2009 08:34:12 +0000

Hello

Introduction
Using online tools has many advantages. One of the most important of them is the information is accessible from anywhere and at any time.
One need that was occurred after using this tools is Synchronizing information with other applications and devices. such as Synchronizing contacts between Mobile, Web and PC.

* The following guide is tested on Kubuntu 9.10 with KDE 4.3.3 environment.

Synchronizing Google Tools with Kontact
Step 1
Installing akonadi-kde-resource-googledata package. The package is available in Ubuntu 9.10 and Debian repositories.

sudo aptitude install akonadi-kde-resource-googledata

Step 2
After installing akonadi-kde-resource-googledata package, you need to add Google resources to Akonadi. Open Akonadi Console:

akonadiconsole

Click Add on Agents tab. Add a `Akonadi Google Calendar Resource` for Google Calendar and add `Akonadi Google Contacts Resource` for Google Contacts.

— Add Google Resources to Akonadi Console

Enter your username without `@gmail.com` in the next window.

— Enter your username

Step 3
After adding a resources open Kontact application :

kontact

Add Contacts
Go to Contact section and add `Akonadi Google Resource` to address books:

— Add `Akonadi Google Resource` to Address Books

Add Calendar
Go to Calendar section and add `Akonadi Google Resource` to calendars:

— Add `Akonadi Google Resource` to calendars

done

P.S.
Ubuntu 9.10 release party held in Tehran, Iran.

Have a good time

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