Pradeep Pant Tech Blog

WEBDAV authentication for Office docunments on SSL enabled sites

Pradeep Pant — Thu, 07 Mar 2013 01:35:31 +0000

As explained in my post related to the Webdav authentication issue using IE for Office documents on Windows 7, I found that the fix will not work for SSL enabled sites. To support HTTPS you will have to add the following lines in /etc/httpd/conf.d/ssl.conf file.

RewriteEngine On

RewriteCond %{REQUEST_METHOD} ^(OPTIONS|PROPFIND)$ [NC]

RewriteRule ^.*$ – [F,L]

Restart httpd

To generate an SSL certificate you can use OpenSSL library

Head First book Perl

Pradeep Pant — Mon, 22 Oct 2012 14:23:43 +0000

Some months back I have purchased 4th edition of Camel book, Programming Perl. I am liking the book and at present focusing on Chapter 6 on Unicode. Well, I was just wondering if the experts in the Perl community have plans to write a Perl book in the Head First series. Well, the obvious answer could be that we already have excellent books then why we need this? But I personally feel that Head First books have quite delightful way of teaching which can shorten learning time. May be this can help in attracting more guys to take a dip in the Perl world in a short time and later one can pick the Camel book and others.

I don’t know if someone had already started writing? But just a thought.

Thanks

PostgreSQL useful tips

Pradeep Pant — Sat, 20 Oct 2012 17:16:57 +0000

I am posting some of the PostgreSQL commands which I use frequently.

Create a new database name testdb

# createdb

e.g: # createdb testdb

Remove a PostgreSQL database

# dropdb

e.g: # dropdb testdb

Backing up a PostgreSQL database

# su - postgres

# pg_dump --blob -Fc testdb -f /var/lib/pgsql/backups/testdb_backup

Restoring PostgreSQL database from back up dump

# pg_restore --dbname=testdb /var/lib/pgsql/backups/testdb_backup

Writing query output to a CSV file:

# \o 'tmp/logs/query_out_dump.csv'

After this operation all the query results will be stored in a CSV file.

Using console again for query output:

# \o

For more on pg_dump and pg_restore pl. check the documentation

Solving the authentication problem while opening Office documents hosted on Apache in IE8/IE9 on Windows 7

Pradeep Pant — Fri, 18 May 2012 18:17:58 +0000

We were facing a problem in IE 8/9 on Windows 7 while accessing Office 2007/ Office 2010 documents hosted on apache/Cent OS 4.6. After some analysis I found the reason and finally ended in a fix. See below my findings and solution. Hope this helps:

The main issue is with the Microsoft’s way of implementing Webdav protocol for accessing web content through Microsoft Web Client. When we click on a Office document then web client sends HTTP /1.1 OPTIONS Request header to server to check the WebDav communication (My server doesn’t have WebDav). In response Apache return 200 OK Response header to Web Client which results in prompting the authentication screen by Windows 7. Well you have option in IE to pass the authentication login automatically but that would be security breach as you will be exposing your machine authentication to internet so I would not prefer that. Best way is to configure Apache to reject these request. This is how i have solved. These changes needs to be done in httpd.conf file in /etc/httpd/conf folder (Cent OS 4.6)

# One way to doing it – Deny access based on request method

RewriteEngine On

RewriteCond %{REQUEST_METHOD} ^(OPTIONS|PROPFIND)$ [NC]

RewriteRule ^.*$ – [F,L]

# Another way to implementing – Deny acess based on user agent (Vista and Windows 7 used same user agent with different version so this Regx shall work for both

RewriteEngine On

RewriteCond %{HTTP_USER_AGENT} ^Microsoft-WebDAV-MiniRedir

RewriteRule ^.*$ – [F,L]

Explanation on Flags:

1. [F] flag causes the server to return a 403 Forbidden status code to the client.

2. Use of the [NC] flag causes the RewriteRule to be matched in a case-insensitive manner. That is, it doesn’t care whether letters appear as upper-case or lower-case in the matched URI.

3. The [L] flag causes mod_rewrite to stop processing the rule set. In most contexts, this means that if the rule matches, no further rules will be processed. This corresponds to the last command in Perl.

Some References:

Microsoft knowledge article on authentication requests from office documents

Apache mod_rewrite rule documentaion

fiddler tool for debugging HTTP requests

Switching from Perl to Python: Speed

Pradeep Pant — Thu, 29 Mar 2012 16:45:59 +0000

A real time comparison. Long live Perl.

http://silicainsilico.wordpress.com/2012/03/26/switching-from-perl-to-python-speed/

Update:

Adding another comparison between various programming languages including Perl. This is bit old post but still relevant.

http://tenser.typepad.com/tenser_said_the_tensor/2006/08/python_vs_perl_.html

Don’t forget to read comments.

Web platform video for developers

Pradeep Pant — Wed, 28 Mar 2012 03:32:33 +0000

I liked the video.. guy is showing some of the cutting edge capabilities of the web platform for developers. For more visit you can visit this link

Enjoy!

Rakudo Star 2012.02 out – and the focus for 2012.03

Pradeep Pant — Wed, 29 Feb 2012 12:04:20 +0000

Release is available on github

https://github.com/rakudo/star/downloads

Delhi.pm Perl Monger user group: Need suggestions

Pradeep Pant — Mon, 20 Feb 2012 14:43:39 +0000

Hello

We have a Delhi.pm Perl Monger Group in New Delhi, India. The group is almost inactive for some years (except monthly mail of mailing list membership detail). I am trying to revive Delhi.pm and need suggestions from community.

I have already created a Google + page to spread the word. Actually, we have a mailing list but I assume that most of the members are either inactive or not working in Perl anymore. I know many active Perl programmers in Delhi but they are not connected.

Do let me know your thoughts to make Delhi.pm active? Comments/advice are most welcome.

Thanks,

Resource on debugging, profiling and benchmarking in Perl

Pradeep Pant — Sat, 18 Feb 2012 16:34:26 +0000

I am listing some of the online resource which really helped me to understand the debugging and profiling in Perl.

Profiling Perl by Simon Cozens

Dr. Dobbs Journel by brian d foy

Wasting time thinking about wasted time by brian d foy

Randal L. Schwartz column on Unix Review

Benchmarking your code by turnstep

Debugging and Profiling mod_perl Applications by Frank Wiles

also do not forget to check chapter 4, 5, 6 of Mastering Perl Book and documentation on CPAN and perldoc.

Any Addition to this list is welcome.

Enjoy Perl.

Added:

Devel::Nytprof

Slides of Tim Bunce talk on Devel::NYTProf YAPC::EU August 2010

Perl Data Language (PDL) Release News

Pradeep Pant — Tue, 07 Feb 2012 14:00:03 +0000

PDL 2.4.10 is released. Another great work from Chris Marshall and PDL Development Team. See this link for official announcement.

You can also checkout the first draft of the PDL book. For existing MATLAB users there is a very good guide which can help in migrating from MATLAB to PDL.

Enjoy the new PDL release and unleash the power of Perl for solving mathematical problems.

Good Luck!