Read First, open the Attachment second No peeking! We mean it!

We recently received news that is going to not only change our lives but
likely everyone who is included in this email. Due to it we have had to
cancel future plans we had on weekends and even a wedding in December.

It’s hard to understand what news could be so good, err great, that we can
be excited about even if it means having to miss a wedding in December.
To find out you will just have to look at the attachment (yes, we give you
permission, go ahead and look…wait! Just kidding, go ahead and look).

After opening the attachment, please scroll down below and read the rest.

With this wonderful news, we want to give everyone the opportunity to
receive announcements from us during this time. We also want to be able
to give everyone the control of whether or not they receive announcements
from us, so please, if you want to receive them sign up at
http://www.wilkin-family.net/announcements/signup.html

Likewise, you can unsubscribe at your convenience too. Bonus points go to
the first person to figure out why we selected the From Address we did for
the announcement emails (you’ll understand when you get your subscription
confirmation email from us).

Feel free to forward this email to any friends, family members, etc. so
that they too may receive the great news and be given the option to
subscribe to our announcements.

Thanks all,
Kami, Matt, Spunky, and Baby Wilkin

Baby Announcement

1. First look up the Printer Name on your Linux box, it is best if it is a single word and under 20 characters. You can typically find this by opening a document, selecting Print and it should be the name in the drop down.
2. Next you will have a script that call rdesktop like so:
   rdesktop -r printer:<YOUR PRINTER NAME ON LINUX>="WINDOWS DRIVER NAME AS IT APPEARS IN ADD PRINTER" <YOUR SERVER IP ADDRESS>
3. Run the rdesktop script and login
4. Go to Printers and Faxes
5. Right-click on the Printer that matches your Linux printer’s name and choose Properties
6. Print a test page!

Note: This only works if you are using a public/private key for authentication via SSH and on a user by user basis. To do this read my post titled, LinkStation Pro Duo, enabling SSH.

To get this to work from a Client machine that runs Linux, you need to install “sshfs”. In short, this allows you to mount a drive/share on your LinkStation Pro Duo onto your client machine. This in turn gives you the opportunity to run rdiff-backup locally which DOES NOT require rdiff-backup –server to be installed on the LinkStation.

Once you have sshfs installed, you will need to create a startup script for your username. Now this will vary depending on the distribution you use, but if you use Ubuntu or one of its derivatives, you can do the following:

1. Setup Directory for Mount Detection
   We need a directory setup on the NAS so that we can tell if the share has already been mounted. This is needed because every time you login via SSH, it will try to mount this drive, and if you are like me and you run your PC 24/7, this could be a problem.
   1. Remote into your NAS via SSH, using ssh <username>@<nas_ip_address>
   2. Create a directory on your NAS that you will put in as the CHECK_FOLDER value in the below script by running
      mkdir <path_to_your_new_folder>
2. Create a .bash_login script
   1. Open your favorite editor (gui, graphical user interface or cli, command line is fine), name it “.bash_login”
   2. Copy the following into the file:
      #!/bin/bash

      CHECK_FOLDER=/mnt/nas-backup/
REMOTE_FOLDER=<username>@<nas_ip_address>:/mnt/array1/Backup
LOCAL_FOLDER=/mnt/nas-backup

      # Check if the NAS Backup Share has been Mounted, if it hasn't mount it
if [ ! -d $CHECK_FOLDER ]; then
sshfs $REMOTE_FOLDER $LOCAL_FOLDER
fi

   3. Replace the values of CHECK_FOLDER, REMOTE_FOLDER, and LOCAL_FOLDER so it suites your setup.
   4. Save the file
3. Logout and log back in
   Your NAS share should be mounted automatically so long as you have a public/private key authentication setup.
4. Setting up your rdiff-backup
   For rdiff-backup, I simply run
   rdiff-backup --exclude-special-files <path_to_directory_to_backup> <mount_location_of_nas_share>
   
   To automate it, I put it as a cronjob that runs every night.

Note on 12/08/2008: I have now started to use rsync as it does not require me to mount the NAS Shares onto my personal computer. It also supports public/private keys allowing me to run it via cronjob daily.

That’s it!

IMPORTANT NOTE: I made a few corrections to the below by adding item 3.6, and updating items 4.4, 5.11, and 5.12. Please read those items over again. If you needed to perform items 5.11 and 5.12 for two PCs, it is important that you use the updated commands.

1. Enable Telnet (temporarily)
   1. Download the acp-commander
   2. Run the .jar file by running
      java -jar acp_commander.jar -t <IP ADDRESS> -o
   3. Login to your LinkStation Pro Duo using (username and password are found on the above link)
      telnet <IP ADDRESS>
2. Enable SSH at Startup
   1. Create an SSH Startup script by typing vi /etc/init.d/sshd.sh
   2. Type ‘i’ to enter Interactive Mode (this enables you to type), then proceed to type the following code:
      #!/bin/sh
test -f /usr/local/sbin/sshd || exit 0

      ACTIVE_FILE=/var/run/active_sshd

      case "$1" in
start) echo -n "Start services: sshd"
/usr/local/sbin/sshd -f /etc/sshd_config 2>/dev/null &
touch $ACTIVE_FILE
;;
stop) echo -n "Stop services: sshd"
killall sshd
rm -f $ACTIVE_FILE
;;
restart) $0 stop
$0 start
;;
*) echo "Usage: $0 start | stop | restart"
exit 1
;;
esac
exit 0

   3. Press the ESC key and type “:wq” to Save and Exit
   4. Make the file executable by running
      chmod +x /etc/init.d/sshd.sh
   5. Backup the original script startup file by running
      cp /etc/init.d/rcS /etc/init.d/rcS.bak
   6. Modify the rcS file to contain the SSH startup script by typing the following:
      vi /etc/init.d/rcS
   7. Press “i” to enter Interactive Mode
   8. Page Down till you see
      echo "** step3 **"
   9. At the end of the next line, add
      sshd.sh
   10. Your change should now look similar to the following:
       for cmd in diskmon.sh drivecheck.sh ftpd.sh atalk.sh httpd.sh smb.sh clientUtil_servd.sh bonjour.sh lsprcvd.sh daemonwatch.sh logrotate_init.sh cron.sh checkconfig.sh ups.sh pwrmgr.sh sshd.sh
   11. Save your changes and exit by pressing the ESC key and typing :wq
   12. Add your SSH script to the Daemon Watch, so if it crashes/closes, it will be started again automatically. Run the following code to edit the list
       vi /etc/daemonwatch.list
   13. Type “i” to enter Interactive Mode
   14. Add the following line to the file
       /var/run/sshd.pid /var/run/active_sshd /etc/init.d/sshd.sh restart
   15. Save your changes and exit bt pressing the ESC key and typing :wq
3. Configure SSH
   1. Backup your original sshd_config file by typing
      cp /etc/sshd_config /etc/sshd_config.bak
   2. Modify the sshd_config file by typing
      vi /etc/sshd_config
   3. Press “i” to enter Interactive Mode
   4. Remove the # in front of the following lines (you need to use the backspace key to do this; you may also need to change some of the ‘no’ values to ‘yes’)
      Port 22
Protocol 2,1

      HostKey /etc/ssh_host_key
HostKey /etc/ssh_host_rsa_key
HostKey /etc/ssh_host_dsa_key

      PermitRootLogin yes
StrictModes yes

      RSAAuthentication yes
PubkeyAuthentication yes

   5. Save the file by pressing the ESC key then typing :wq
   6. Start the SSH Server by running /etc/init.d/sshd.sh start
4. Create new Home folders for each user
   You will need to do the following for every user you have created!
   1. Create the users via the Web Interface first, once the users are created, start Step 2 for each user
   2. Create a directory for the user by typing (replace <username> with the actual username)
      mkdir /home/<username>
   3. Give the user permission to that folder by typing
      chown <username>.<group> /home/<username>
      Now this is a bit tricky, depending how you setup the groups. You want to give the permission to a valid user and a group the user is part of. For example, if you have a user named “matt” and a group named “contributor”, then your command would be
      chown matt.contributor /home/matt
   4. Finally, make sure the directory has the correct permissions by running the following command
      chmod 0755 /home/<username>
   5. Set the user’s home directory by running
      usermod -d /home/<username> <username>
5. Create public/private key pairs for each user
   You will need to do the following for every user you have created!
   I am only going to go over the commands you would use in Linux as I haven’t tried this with PuTTY yet. You will need to do these steps as “each user”. In other words, you will have to logout on your PC, login as the next user and repeat the commands (advanced users can use su <username> to login as an additional user without logging out as their own).
   1. Run the following command in Terminal or Konsole on YOUR PC
      ssh-keygen
   2. Leave the file name as “id_rsa”
   3. If you want a passphrase enter it here, otherwise, leave it blank (I left mine blank)
   4. Next run the following command to generate a SSH 2 key
      ssh-keygen -t dsa
   5. Leave the file name as “id_dsa”
   6. If you want a passphrase enter it here, otherwise, leave it blank (I left mine blank)
   7. Next copy the files to your LinkStation by running
      scp .ssh/*.pub <username>@<IP ADDRESS>:/home/<username>
   8. Next login to the LinkStation via SSH using
      ssh <username>@<IP ADDRESS>
   9. Once login run the following command to create your SSH key directory
      mkdir .ssh
   10. Make sure the permissions are set properly by running
       chmod 0700 .ssh
   11. Load the public key for SSH 1 by running
       cat id_rsa.pub >> .ssh/authorized_keys
   12. Load the public key for SSH 2 by running
       cat id_dsa.pub >> .ssh/authorized_keys2
   13. Make sure the public key entries for SSH have the correct permissions by running
       chmod 0600 .ssh/authorized_keys*
   14. Exit out of the LinkStation by typing “exit”
   15. Try step 8 again and make sure it did not ask for your password this time (if you entered a passphrase, you will be prompted for your passphrase)

Download the sshd_config.zip

However, let me state, that I do want to see Flex Builder 3 ported to Linux. I could then ditch my Windows Virtual Machine and run things natively, but that is my only complaint at this moment.

So why do I love Flex?
Flex is just easy to use, the components built it are amazing and you have the ability to build components on your own too! Much like Server Controls in .NET, .NET gives you a TON to begin with and you can create your own as well. However, this is for Flash! That is extremely important to acknowledge, as I do not have to have Macromedia Flash MX or whatever the latest version is on my PC to build a Flash application now.

Not only do I love being able to build a Flash application without Macromedia Flash, but I also love how it can work with an infinite number of backends without a lot of effort. Got a web service you want to plugin to? No problem, how about an RSS feed? Again, No problem. Well how about just a plain HTTP stream with a custom format? No Problem! I mean literally, you can plugin to any service that can send back a response. If it is a custom type of response, then you can write a routine to read your custom format. However, if you are using a Web Service, be in written in .NET and it returns an XML stream, then you literally have to do nothing! It will read it without any custom code from you, the developer. And that my friends is the “cream of the crop”.

So where do we go from here?
I am going to be doing a lot of things with Flex fromt his point on. I was just totally amazed by the simplicity and yet the complexity you can have within it. I still have a lot to test. Updating the grid’s data when it has changed, and similar events. But time will tell and so far Adobe has bought me back with this wonderful technology. Just bring it to Linux and I will move right next to your head-quarters Adobe!

To keep a long story short, the architecture I used was not followed in this piece and now I am paying the price for something I didn’t do. The original code was developed so the code would do 50-70% of the work for me dynamically. Yes, this has performance cost implications but they were minimal (1-2 seconds at best), but the time it saves is nearly 60-75% of development time.

Now the particular piece I am referring to does a lot of output work. It takes the data inputted by the user and develops a results page to the user describing the information the user typed. Now, to make my life easier, I build a hash table of the user’s values and associate them with a code. The code is related to a table that defines the text to display regarding that entry.

By creating code to associate the hash table data with the database table, the results page can be generated dynamically saving me the countless time of programming each possibility the user can come up with.

Thus, sometimes it is smarter to go a dynamic route at the cost of performance, than it is to develop the most efficient masterpiece you can imagine.

That is my food for thought.

So just like window.screenLeft versus window.screenX, window.screenTop only works in IE and window.screenY works in everything else. So here is the code I used to setup a window.*property*:

// Find Top Boundary of current Window
function FindTopWindowBoundary()
{
	// In Internet Explorer window.screenTop is the window's top boundry
	if (window.screenTop)
	{
		return window.screenTop;
	}

	// In Firefox window.screenY is the window's top boundry
	if (window.screenY)
		return window.screenY;

	return 0;
}

window.topWindowBoundary  = FindTopWindowBoundary;

Then just like the horizontal setup, I needed to find the Monitor’s Top Border. Like the horizontal counter-part, you need to check the negative y-axis scenario, which left me with this code:

// Find Top Boundary of the Screen/Monitor
function FindTopScreenBoundary()
{
	// Check if the window is off the primary monitor in a positive axis
	// X,Y                 S = Screen, W = Window
	// 0,0     ----------
	//        |          |
	//        |          |
	//        |        S |
	//         ----------
	// X,Y
	// 0,1280  ----------
	//        |  ---     |
	//        | | W |    |
	//        |  ---   S |
	//         ----------
	if (window.topWindowBoundary() > window.screen.height)
	{
		return window.topWindowBoundary() - (window.topWindowBoundary() - window.screen.height);
	}

	// Check if the window is off the primary monitor in a negative axis
	// X,Y                   S = Screen, W = Window
	// 0,-1024   ----------
	//          |  ---     |
	//          | | W |    |
	//          |  ---   S |
	//           ----------
	// X,Y
	// 0,0       ----------
	//          |          |
	//          |          |
	//          |        S |
	//           ----------
	// This only works in Firefox at the moment due to a bug in Internet Explorer opening new windows into a negative axis
	// However, you can move opened windows into a negative axis as a workaround
	if (window.topWindowBoundary() < 0 && window.topWindowBoundary() > (window.screen.height * -1))
	{
		return (window.screen.height * -1);
	}

	// If neither of the above, the monitor is on the primary monitor whose's screen Y should be 0
	return 0;
}

So now that we have the Top and Left boundaries written, we can open a window in any setup (2 monitors to 4 monitors to X monitors) using the following and be guaranteed that the new window will open in the same monitor as the parent window (except for IE where IE will not open windows in a negative axis).

window.open(thePage, 'windowName', 'resizable=1, scrollbars=1, fullscreen=0, height=200, width=650, screenX=' + window.leftScreenBoundary() + ' , left=' + window.leftScreenBoundary() + ',screenY=' + window.topScreenBoundary() + ',top=' + window.topScreenBoundary() + ', toolbar=0, menubar=0, status=1');

And thus the finale of opening a child window in a dual, quad, whatever monitor setup.

Today, I got my PC setup with Dual Monitors and was asked to solve the following problem:

“When the user clicks on a link that opens a new window using window.open. Make the window appear on the same monitor as its’ parent.”

So I got started. Quickly I discovered that window.screenLeft (for IE) and window.screenX (for everyone else) will tell me where the window’s border is on the desktop. So what better to do than to throw that in a window.*property* which gave me this code:

// Find Left Boundry of current Window
function FindLeftWindowBoundry()
{
	// In Internet Explorer window.screenLeft is the window's left boundry
	if (window.screenLeft)
	{
		return window.screenLeft;
	}

	// In Firefox window.screenX is the window's left boundry
	if (window.screenX)
		return window.screenX;

	return 0;
}

window.leftWindowBoundry = FindLeftWindowBoundry;

Next, I needed to find the monitor’s left border. Soon after, I figured out that there is no property currently for this, however, you can get the width of the current monitor your window is on by using window.screen.width. There is a big pitfall that needs to be considered, you can have a monitor whose left border starts with a negative X-axis (ie: -1024×0 to 0×768).

So that left with me the following code:

// Find Left Boundry of the Screen/Monitor
function FindLeftScreenBoundry()
{
	// Check if the window is off the primary monitor in a positive axis
	// X,Y                  X,Y                    S = Screen, W = Window
	// 0,0  ----------   1280,0  ----------
	//     |          |         |  ---     |
	//     |          |         | | W |    |
	//     |        S |         |  ---   S |
	//      ----------           ----------
	if (window.leftWindowBoundry() > window.screen.width)
	{
		return window.leftWindowBoundry() - (window.leftWindowBoundry() - window.screen.width);
	}

	// Check if the window is off the primary monitor in a negative axis
	// X,Y                  X,Y                    S = Screen, W = Window
	// 0,0  ----------  -1280,0  ----------
	//     |          |         |  ---     |
	//     |          |         | | W |    |
	//     |        S |         |  ---   S |
	//      ----------           ----------
	// This only works in Firefox at the moment due to a bug in Internet Explorer opening new windows into a negative axis
	// However, you can move opened windows into a negative axis as a workaround
	if (window.leftWindowBoundry() < 0 && window.leftWindowBoundry() > (window.screen.width * -1))
	{
		return (window.screen.width * -1);
	}

	// If neither of the above, the monitor is on the primary monitor whose's screen X should be 0
	return 0;
}

window.leftScreenBoundry = FindLeftScreenBoundry;

Now that the code is written, you can now use window.open to open a window on the monitor the parent window is on.

window.open(thePage, 'windowName', 'resizable=1, scrollbars=1, fullscreen=0, height=200, width=650, screenX=' + window.leftScreenBoundry() + ' , left=' + window.leftScreenBoundry() + ', toolbar=0, menubar=0, status=1');

Oh yeah, IE has a bug in it that prevents opening windows with window.open in the negative X-axis. You have to use windowName.moveTo(-1024, 0); to move it to the negative X-axis.

Enjoy!

If you do this, you are guaranteed the following:

1. It is easy to maintain and understand the code you wrote months later
2. Chances are your application will not be the quickest in response
3. You will make use of techniques you fully understand than trying to adapt ones that you are unfamiliar with and may implement wrong

So how does JSON differ from returning XML in your AJAX requests? Lets first look at the advantages of XML.

1. Standardized and easily serialized into via .NET
2. The XML is easy to read all within itself
3. You can make use of XSLT, DTDs, etc

How about disadvantages of XML?

1. It is slow in comparison to JSON
2. It can be clumsy when not designed properly

Now for the advantages of JSON:

1. It is faster than XML to parse in JavaScript
2. There are addin’s you can install in .NET or a library in PHP to serialize a JSON string from an object
3. It is hard to make this clumsy as it is based on the Object Design

And the disadvantages of JSON:

1. It is harder to read the serialized output
2. You can’t use XSLT, DTDs, or something of the sort to validate or style the request

As for myself, I am a JSON person. I didn’t used to be though. My original AJAX applications were focused around XML primarily because I could make use of an XSLT and I always validated against a schema. However, JSON has won me over due to speed. JSON’s speed is just ridiculously fast and it showed when I converted a major application over to it. I saved nearly a third of the time it took to do a fairly simple task.

However, pick the poison that you understand most, otherwise, it could have detrimental affects.

Kiosk, uses Ajax in interesting ways to provide a better experience, but with that, the Ajax applications were built as each page was assembled. This caused functionality across pages to get a bit messy or functionality shared across pages to get thrown into individual files. Well the problem with individual files, is that is yet another file for the browser to download.

So before I get any further, let me discuss refactoring and how it can solve many performance binds your application may be experiencing.

To start off, refactoring is taking common code, or code that is used across pages or frequently and moving it to a more global location so it can be called easier and the code only has to be written once.

So where can this help?

• First of all, by refactoring code into a single global file, you can limit the number of HTTP requests if that file is accessible via the web. Since your common code is in a single file, the browser only has to fetch that code once, and will then likely cache that file for each page after, giving you even better performance.
• Secondly, by placing the common code in a global method/function, you are writing less code. As now when you need to call that code on your second page, it is already written, so just call the function. Otherwise, you would need to write the code all over again.
• Thirdly, less code equals smaller files. By refactoring your code, you can have smaller file sizes and in turn that is quicker to download, quicker to parse, and quicker to execute.

Now in my situation, I took about 4 JavaScript files and combined them into a single file adequately named “general.js”. The file contained code to automatically log the user out after a set amount of inactivity in the UI (User Interface). Secondly, it contained the version checking mechanism calls that see if they are running the latest version of the software. Unfortunately, those are the only two things it does right now, but as the project progresses, I am sure more utilities will get added in this file.

My next task is to refactor the Data Grid functionality so it is 1) XHTML, 2) easy to build complex columns with complex rows, 3) customizable by identifying StyleSheet classes for the columns and rows. Hopefully, I can get my head around this idea and get it working with little trouble to the programmer.

So what can you think of that you need to refactor? What performance gains do you suspect you will achieve with the refactoring you do? Any performance markers?