Scattered Thoughts

.htaccess (which stands for Hypertext Access) are text files that are used to make configuration changes on an Apache Server. It contains a series of ‘directives’ for the server to follow, these directives are then applied to the folder the .htaccess file is placed in and also to all its sub-folders.For htaccess novices, it is important to note that small syntax errors can result at times in serious issues, so it is always a good idea to always backup your site before making major changes to the .htaccess file. I am no expert in .htaccess, but here are some directives I have found really useful.

The following are some of the most useful directives I have used:

1. URL Canonicalisation

Some search engines treat www.yoursite.com and yoursite.com as 2 separate sites, now if you are interested in SEO (and pretty much everyone nowadays is) this could lead to bigger issues. Using .htaccess you can make sure that all users will see the url you want them to see.

RewriteEngine On

RewriteCond %{HTTP_HOST} ^kunaal84.com$ [NC]

RewriteRule ^(.*)$ http://www.kunaal84.com/$1 [L,R=301]

The above piece of code returns a 301 permanent redirect error if it receives a request for “kunaal84.com” and redirects the user to “www.kunaal84.com”.

2. Restrict access

A Single File

order allow,deny

deny from all

Add the above block of code and replace the file name “restricted_file.html”, with the name of the file you want to restrict access to.

File Types

Order Allow,Deny

Deny from all

Add the above block of code to restrict access to all files of type “.php and .css”, add more files as you see fit.

3. Disable Directory Listing

If you are missing a default page in your root folder, everything in it becomes visible and accessible to any visitor, the following code directive prevents the directory from listing its files and returns a “Forbidden” message

Options All -Indexes

4. Change Default Index Page

You can tell your server to show another file as the default index file instead of the usual index.html/index.htm
For example to show new_index_file.html as the default file use

DirectoryIndex new_index_file.html

5. Parse an Html File Using the PHP Parser

Sometimes you might need to parse your html files using the php parser, to do this use the following directive

AddType application/x-httpd-php .html

6. Use Custom Error Pages

Use the following directive if you want to display your own 404 page instead of the server default

ErrorDocument 404 /errors/404.html

7. Redirects

The following directive carries out a simple 301 redirect

redirect 301 /directory/old_file.html http://www.my_domain.com/new_directory/newfile.html

8. Stop Hotlinking

To prevent bandwidth thieves, use the following block of code. This prevents hotlinking of .gif, .jpg and .png files (more can be added)

RewriteEngine on

RewriteCond %{HTTP_REFERER} !^$

RewriteCond %{HTTP_REFERER} !^http://(www.)?your_domain_name.com/.*$ [NC]

RewriteRule .*.(gif|jpg|png)$ - [F,L]

If you prefer to teach them a lesson, serve some alternate content use

RewriteEngine on

RewriteCond %{HTTP_REFERER} !^$

RewriteCond %{HTTP_REFERER} !^http://(www.)?your_domain_name.com/.*$ [NC]

RewriteRule .*.(gif|jpg|png)$ http://www.your_domain_.com/alternate_image.bmp [R,NC,L]

Bibliography:
Apache mod_rewrite
htaccess tutorial

Cool Software:
Automatic .htaccess Generator