Most common database used with Rails is mySQL but if you ever need to use SQL Server, here is a quick how to.

I am using  Windows Vista, SQL Server 2008, Rails 2.2.

1)  Install  activerecord-sqlserver-adapter gem

 > gem install activerecord-sqlserver-adapter

2) Create a new Login for this new database (say testuser) using SQL Server Management Studio

3) Create a new database in SQL Server 2008 for your project (say testproject) and choose testuser as Owner

4) Create a new ODBC DNS

Control Panel -> Administrative Tools -> Data Sources (ODBC)

Add a new ‘User DSN’,  choose SQL Server,  give a name for DSN (say testprojectconn) then configure SQL Server authentication.

5) Now create your rails application as usual.  Configure db connection using database.yml as follows

  adapter: sqlserver
  mode: odbc
  dsn: testprojectconn
  host: localhost
  username: testuser
  password: testpass
  encoding: utf8

Thats it!

This blog post deals with VPNC (http://www.unix-ag.uni-kl.de/~massar/vpnc/) : an alternative to Cisco’s linux version client.  If you happy with cisco’s client and were able to install it successfully then you can skip the rest of the blog. 

Most of the information can be found at original sources http://wiki.centos.org/AdditionalResources/Repositories/RPMForge  and http://wiki.centos.org/HowTos/vpnc 

Only issue you might face is installing yum prorities using yum. That is broken in CentOS 5.3 (atleast til I tried). So here are the steps involved. 

1) Install Yum Prorities

Install prorities using rpm instead of yum.

nano /etc/yum/pluginconf.d/priorities.conf

3) Update Proirities for repo files

nano /etc/yum.repos.d/CentOS-Base.repo

4) Install rpm forge

5) Update prority for rpmforge repo file

6) Update yum to start using priorirites and rpmforge as source.

7) install VPNC

Now vpnc is installed.  Follow http://wiki.centos.org/HowTos/vpnc to know how to use it.

Once in a while we been in situations where you need to quickly understand/analyze a database given to you by others.  We can go through each table and try to understand but it is usually lot simpler if you can visualize all the tables involved and relationships between those.  Enter SchemaSpy: a free tool to do that.    For sake of specifics, say the database given is MySQL and your pc is running some version of Windows.

A. Download and Install Pre-requsites (if you dont have already)

• Graphviz  (http://www.graphviz.org/Download_windows.php)
  • use MSI installer (see warnings specific to vista on the download page)
• Java (http://www.java.com/en/download/index.jsp)
  • Download and install Java as usual.
• JDBC driver for mySQL ( http://dev.mysql.com/downloads/connector/j/5.1.html)
  • Download driver and extract to a known location (say C:\mydblayout)

B. Download latest SchemaSpy Jar File  from http://sourceforge.net/projects/schemaspy/files/   (In my case it is schemaSpy_4.1.1.jar)  to a known location (using same C:\mydblayout)

Now run the schemaspy to generate report (html format) for database ”mytestdb”  which is sitting at a local mySQL server.

See how -dp flag is used to point to jdbc driver.  The above command creates a folder called “mytestdb_report”  with all the nice html files.  Just open the “index.html” file.

For example output see http://schemaspy.sourceforge.net/unifieddb/characters/index.html

For more details, look at web page of  this wonderful SchemaSpy (http://schemaspy.sourceforge.net/) written by John Currier.

Close all IE8 windows…

if you have any IE window open, then VS cant start debugger….

Its not a problem with VS2008 onwards.

To be more precise, the security hole is with the network (AT&T network) IPhone uses. I noticed this problem while working on a Voice-enabled application using Asterisk and surprised to see that my voicemail is wideopen to public. Then later found out that this has been reported earlier by various folks (here and here) but seems like it is not fixed yet. So if you own an IPhone (or any other phone for that matter) with AT&T network, please keep  reading and I show you how to fix the problem yourself.

So what is the problem?

Others can listen to your voice mail, change your personal greeting and other settings.   AT&T voicemail identifies user based on incoming caller ID, so if callerID matches the phone # you are calling from, it assumes that you are calling yourself to check voice mail then it simply goes to voice mail (if you don’t have password set).

Am I protected or Not?

 Call yourself with your phone (by dialing 1 or dialing your number).  If you are prompted for a password, then you are fine.  If it takes your directly to  voice mail menu, then you are NOT secured. See how to set password below.

How to protect my voice mail?

Dial 1 to call Voicemail from your phone

Press * to get to the voicemail Main Menu

• Press 4 for Personal Options
• Press 2 for Administrative Options
• Press 1 for Passwords
• Press 2 to turn password on
• Select any random 4– to 14–digit password

Why I am blogging this?

 I don’t know if new AT&T users may be forced to set password or not, but when I got my phone couple of years back and my voicemail was setup without password.  It ended up that most of my friends with IPhone also don’t have password setup for voicemail because simply they are not aware of the security hole.   With easy access to Open source PBX like Asterisk or spoofing calling cards, its not hard to exploit this security hole.  So if this blog helps people to realize how important is to set password, then my job is done.

Disclaimer

The opinions expressed in this blog post are my own and not of any company. The usual standard disclaimer applies, especially the fact that I am not liable for any damages caused by direct or  indirect use of the information.  I bear NO responsibility for content or misuse of this information or any derivatives thereof.  This post is NO WAY intended  to blame anyone, especially  AT&T.  They may have already posted about this issue somewhere on their website. 

If you download any Pre-Janauray Design template from http://www.asp.net/mvc/gallery/default.aspx?supportsjs=true and trying to test with latest MVC  Release (after following ReadMe.txt),  chances of you getting an ugly error like below are real high.

So how to make these template with new version? You can with very few changes to site.master page (This following example is for Bluebubbles template but this may work for most of the templates)

Views/Shared/Site.Master

Page Directives Before

Page Directives After Changes

Head Section Before

Head Section After Changes

I was looking at Peter Bromberg’s post ”Build a dynamic progress page” which is about creating a “Loading” page for time-taking asp.net webpages. The problem with Peter’s solution is if your destination page has more than one query string params, then it wont work. Another small problem is non-standard DOM access which wont work in non-IE browsers (it was written almost five years back so it might not a big concern at that time)

Here is the modified code to make it work with query string AND non-IE browsers.

The basic idea is having a transient ‘Loading’ page which loads the time-taking page in the background and in meantime show a nice animated progress bar. Lets name our middle page ‘loading.aspx’

loading.aspx

Header section has javascript code to show, hide progress bar while loading the destination page

Body has nothing but visual element for progress bar. Note that we are calling Begin() on body load and End() on unload.

loading.aspx.cs

In the code-behind, destinal URL is generated.

Finally, to use this page to call a time-consuming page (say  longloadingpage.aspx) which takes ID1 and ID2 as query params  simply call

/loading.aspx?destPage=longloadingpage.aspx?ID1=123&ID2=345

For folks in houston area, remember that this weekend we have wonderful Techfest at University of Houston. Visit http://www.houstontechfest.com and register.  It features lot of exciting sessions in .NET, Java and Rails. And best of all its free.

See you there!

I wrote a similar blog post last year if you are interested on setting up a production server on Linux( BTW which made lot simpler by Passenger now and recommended way to do it). But there are some cases, we have to deploy to MS servers. In the following article lets us look at doing the same on a Windows 2008 Server (I think it works for windows XP or 2003 too).

If you are like me, you usually develop RoR applications on linux (I am talking about non-mac people, anyway…).  My setup is usually looks like this : XUbuntu + Netbeans  + Mysql/Sqlite3 + Apache + Phusion Passanger.  Assuming you got all your development done andi it’s called  “MyApp”.

On Windows 2008 Box

Step 1:  Install Ruby, gems and rails

Get Ruby 1.8.6 One-Click Installer (from http://www.ruby-lang.org/en/downloads/) and make sure to install gems.

Then installing rails is a breeze. Open a command line window and type

Step 2: Install mongrel & mongrel_service

Step 3 : Install Apache and enable required modules

A. Get Latest msi version for windows (currently apache_2.2.10-win32-x86-no_ssl.msi) from http://httpd.apache.org/download.cgi

B. Install as a service.

C. Enable required modules by uncommenting these following line in httpd.conf file (which can be found at C:\Program Files (x86)\Apache Software Foundation\Apache2.2\conf\

if you followed the default installation)

D. Start the server to makesure it starts and runs OK. If there is a problem with config file you would see an error.

Step 4 : Install database drivers

This really depends on your database. Remember that for sqlite3, if you are having trouble installing latest

drivers, try giving a version no as follows.

Step 5 : Create a skeleton rails application

I am assuming we are keeping our rails application in C:\railsapps\

So create the new rails application by changing to that directory and running

The reason for creating a skeleton instead of just copying our application from Linux, is that the way some files are created on windows may not be same as linux.  So let it create a dummy app and test it to make sure, its able to pullup the welcome page.

Step 6 : Copy your application Files over to windows

The directories usually copy are

(Again, this is highly dependent on your application. May be you didn’t have any custom javascripts or stylesheets in that case you could skip public/ folder all together)

Step 7:  Load Database Schema into production db

Step 8 : Create Multiple Mongrel Server Instances and start them as automatic

I am creating 3 instances here

which creates three services (you could see them Start>>Administrative Tools >> Services Panel). By default the services are created as  “Startup Type — Manual”. Set that to “Automatic” so that they will start back again if you reboot the server.

Step 9: Setup Apache

In the apache’s httpd.conf file make sure to have these following lines

Then make your  conf/extra/httpd-vhosts.conf  File look like this

#——- Start of http-vhosts.conf file ———————————–

If you ever used apache’s mod_rewrite module then you dont need any explanation. If you don’t, then breif explanation wont make much sense to you either….

Becareful with name of Proxy balancer and make sure to use exact name in last RewriteRule (in the above case its Myapp_cluster), then you should be fine.

Step 10 :  Start the mongrel services and Restart Apache.

Now when you go to http://localhost/  you should be sent to one of the 3 servers of balancer and see the application.  If you see broken images or ugly layout, then it means you didnt copy my “http-vhosts.conf” file properly!  Have a careful look at <Directory> directive again. You would know.

Happy programming and happy holidays.  Ciao.

p.s.  If you want to run multiple rails applications on same server like MyApp1, MyApp2…., have a look at rails.conf I used in “Fedora production setup“. By adding another balancer and modifing RewriteRules littlebit, its not that tough.

One of my co-workers asked me if I know on top of my head to remove additional white spaces in a sentence using C#.   We all know that Trim() removes white spaces at front and end…. and “Replace” can be used to remove all white spaces in string   BUT  he dont want to remove all spaces …he just wants to remove extra spaces if any….

Input :  This is              a test sentence   with    some                 spaces
Desired Output :   This is a test sentence with some spaces

System.Text.RegularExpressions.Regex.Replace(input, @”\s+”, ” “);

Remember that this removes all whitespace characters including tabs, newlines  etc…  which is he wants anyway!