Better Default Directory Views with HTAccess

Beautify your default directory listings! Displaying index-less file views is a great way to share files, but the drab, bare-bones interface is difficult to integrate into existing designs. While there are many scripts available to customize the appearance and functionality of default directory navigation, most of these methods are either too complicated, too invasive, or otherwise insufficient for expedient directory styling. In this comprehensive tutorial, you will learn how to use the built-in functionality of Apache’s mod_autoindex module to style and enhance your default directory views with a smorgasbord of stylistic and functional improvements.

Before diving in..

Default directory views are very common on the Web. Any directory that does not contain a default index file, such as index.html, index.php, default.asp, or something similar, may present its contents via default directory view. Whether or not default directory views are enabled depends on several factors.

First, your server configuration must allow default directory listings. For shared hosting, this option may be specified via the account’s control panel. Once directory listings are allowed at the server level, the directory itself needs to have its file permissions set to allow access (this is generally the case). Also, there must be no interference from other scripts, software, or other apps.

With all of these conditions met, you may gain granular control over which directories list their contents and which do not by using per-directory HTAccess files. Importantly, default directory views should be implemented intentionally, according to the specific content delivery requirements of the site. Unintentional display of directory contents may jeopardize site security if loopholes or potential exploits are discovered within unintentionally exposed scripts. For this reason, it is always a good idea to disable default directory views sitewide by default. On Apache-powered servers, this is easily accomplished with a single line of HTAccess:

# DISABLE DIRECTORY VIEWS
Options -Indexes

With that directive placed in the root HTAccess file of your site, directory listings will be disabled throughout your entire site. Then, once you have implemented this security measure, you may (re)enable directory views for any specific directory by creating an HTAccess file for the directory and adding the following directive to it:

# ENABLE DIRECTORY VIEWS
Options +Indexes

At this point, your site is protected against unwanted directory listings and ready to display directory contents via default view for a specifically chosen directory. For the sake of this tutorial, let’s assume we are sharing displaying some choice Pink Floyd MP3s from within a directory called (creatively enough) “floyd”:

Default directory view for the “floyd” directory

Now let’s have a little fun styling, tweaking, and enhancing that boring default directory view with some HTAccess magic. For the sake of maintaining order throughout this tutorial, we will walk through the construction of a completely functional HTAccess file capable of transforming any default directory listing into a thing of functional and aesthetic beauty!

Step 1: Preliminary Directives

The first thing we want to do is secure our directory’s HTAccess file against attacks. We add the following code to the HTAccess file of our target directory (the one for which we have enabled default directory views):

# STRONG HTACCESS PROTECTION
<Files ~ "^.*\.([Hh][Tt][Aa])">
 order allow,deny
 deny from all
</Files>

For more information on this technique, check out my article, Improve Site Security by Protecting HTAccess Files. Let’s move on..

Step 2: Precautionary Measures

When implementing HTAccess directives, it is always a good idea to test for the presence of the required Apache module before its invocation. Apache has built-in module “testing containers” (or whatever they’re called) that are designed for this purpose:

# DIRECTORY CUSTOMIZATION
<IfModule mod_autoindex.c>
 .
 .
 .
 [ HTAccess directives relying on mod_autoindex go here ]
 .
 .
 .
</IfModule>

Add that code to your now-expanding HTAccess file (make sure you remove the six dots and the bracketed information!). We will be inserting all subsequent code in between these opening and closing module containers.

Step 3: Configurational Tricks

Apache’s IndexOptions directive provides many useful configurational options. Rather than list them all here, we will choose a couple of key options to get us started and then explore additional options as needed. For a complete list, check out the official mod_autoindex manual at the venerable Apache website.

Returning to our Pink Floyd MP3 directory, let’s assume that we want to enable the following features:

• Fancy indexing — display of additional file information, including extra sorting and configurational features, file icons and descriptions, etc.; without this option enabled, directory contents are returned in a simple unordered list format
• Folders first — always display any subfolders before individual files, regardless of specified sort order
• Auto-width Name column — we want the name column to automatically resize according to the length of the longest file/folder name; without this option enabled, long file and folder names will be truncated unless we specify an accommodating column width.
• Auto-width Description column — we want the description column to automatically resize according to the length of the longest file/folder name; without this option enabled, long file and folder descriptions will be truncated unless we specify an accommodating column width.
• Suppress the HTML preamble — by default, Apache automatically includes the opening HTML elements (e.g., <html>, <head>) for the markup comprising the directory listing; however, we want to disable this behavior because we will be using our own custom header (and footer) files.

Amazingly enough, all of this functionality is invoked with a single line of code:

# SET INDEX OPTIONS
IndexOptions IgnoreCase FancyIndexing FoldersFirst NameWidth=* DescriptionWidth=* SuppressHTMLPreamble

Notice the two options for specifying the column widths, NameWidth and DescriptionWidth. Note also the use of the wildcard operator ( * ) for the keen auto-width columns. Of course, any value (in pixels) may be specified here, depending on your specific needs. And, while we’re at it, let’s specify the default directory display order:

# SET DISPLAY ORDER
IndexOrderDefault Descending Name

After placing these directives within the previously specified IfModule container, our Pink Floyd directory view looks like this:

Options-modified directory view for the “floyd” directory

As you can see, not much has changed in terms of appearance, but don’t worry, we’ll get to that next..

Step 4: Accessing and Modifying Markup

The key to customizing the look and feel of the default directory listing is the ability to modify and customize the <head> region of the document markup. Even though they look plain and boring, default directory views are displayed via good ‘ol fashioned HTML. Sadly formatted HTML perhaps, but HTML nonetheless. Each directory view consists of three different “chunks” of HTML:

• The Header — by default automatically generated by Apache
• The Directory Listing — necessarily generated by Apache
• The Footer — referred to as the “Readme” file

Fortunately, the Apache Wizards have provided a way to override the default header and footer files, thereby enabling us to include our own elements within the document <head>, like CSS styles, JavaScript, or anything else we desire. Likewise with the footer, we may add any sort of custom content, links, information, notes, or whatever. To specify custom header and footer files, we add this to our HTAccess file:

# SPECIFY HEADER FILE
HeaderName header.html
 
# SPECIFY FOOTER FILE
ReadmeName footer.html

Each of these two files, header.html and footer.html, must be created and properly located according to the specified path. In this case, we are simply placing the files in the same directory as the HTAccess file, so no other path information is required. These files may be placed anywhere on the server, however, so long as they are accessible via correct file paths. Given our preconfigured options, here is the minimum amount of markup that must be included within the custom header file:

<html>
	<head>
		<title>Directory Title</title>
	</head>
	<body>
		<h1>Directory Title</h1>

Technically, we only need the opening <html> and <body> elements, but it is nice to include a title for the document as well. Note that by omitting the previously defined SuppressHTMLPreamble option, Apache will generate the required opening markup, regardless of whether or not a custom header file is included, and regardless of whether or not the custom header file already includes it. Now, to style the entire directory listing, we simply add our desired CSS styles to the <head> region. Before applying CSS styles, however, it helps to know which HTML elements we have at our disposal. With FancyIndexing enabled, directory listing markup includes the following elements:

• body
• img
• pre
• h1
• hr
• a

All default directory listings generated by Apache (with FancyIndexing enabled) employ these elements to construct the page. The challenging part of styling the default markup involves Apache’s use of <pre> tags to enclose all markup for the directory listing itself (i.e., the middle part of the document which cannot be customized). Here is the markup used for our exemplary /floyd/ directory:

<pre><img src="/icons/blank.gif" alt="Icon "> <a href="?C=N;O=A">Name</a>                    <a href="?C=M;O=A">Last modified</a>      <a href="?C=S;O=A">Size</a>  <a href="?C=D;O=A">Description</a><hr><img src="/icons/back.gif" alt="[DIR]"> <a href="/">Parent Directory</a>                             -   
<img src="/icons/sound2.gif" alt="[SND]"> <a href="Seamus.mp3">Seamus.mp3</a>              21-Feb-2005 13:15  1.3M  
<img src="/icons/sound2.gif" alt="[SND]"> <a href="San%20Tropez.mp3">San Tropez.mp3</a>          18-Jul-2005 21:42  2.4M  
<img src="/icons/sound2.gif" alt="[SND]"> <a href="One%20of%20These%20Days.mp3">One of These Days.mp3</a>   10-Oct-2006 10:15  3.0M  
<img src="/icons/sound2.gif" alt="[SND]"> <a href="Fearless.mp3">Fearless.mp3</a>            25-Oct-2006 10:13  5.6M  
<img src="/icons/sound2.gif" alt="[SND]"> <a href="Echoes.mp3">Echoes.mp3</a>              25-Aug-2005 15:08  8.6M  
<img src="/icons/sound2.gif" alt="[SND]"> <a href="A%20Pillow%20of%20Winds.mp3">A Pillow of Winds.mp3</a>   27-Jun-2006 12:38  4.6M  
<hr></pre>

As you can see, the designers of this portion of the markup are depending heavily upon the <pre> element for the layout of the page. As empty/white/blank spaces are preserved when presented as preformatted text, the different columns are established via varying amounts of white space. This layout technique makes it difficult to style things like line-heights, margins and padding for the individual lines of text. Fortunately, there are workarounds for this, such as styling the image elements to affect line height, etc..

Before styling our document, let’s have a quick look at the custom footer file we will be using:

<pre><em>Customize your own footer text!<br />Add information and links!</em></pre>
<pre><a href="http://domain.tld/" title="Home">Return to Home Page</a>
<a href="http://domain.tld/search/" title="Search">Search this Website</a>
<a href="http://domain.tld/contact/" title="Contact">Contact Webmaster</a></pre>
</body>
</html>

Here, we could include any information we desire. For the sake of this tutorial, I have simply added a few generic links as an example. Note that you must close the <body> and <html> at the end of the document. Here is a screenshot showing our directory listing at this point:

“floyd” directory with custom header and footer [full view]

Step 5: Styling the Document with CSS

Before we begin styling the page, let’s use HTAccess to hide the footer.html file from appearing in the directory list. Also, if we were using a name other than “header” for the header file, we would need to hide it as well. Regardless of what you decide to name these files, preventing their listing in the directory is as easy as adding the following line to your HTAccess file (beneath the custom header and footer directives):

# IGNORE THESE FILES
IndexIgnore header.html footer.html

Apache’s IndexIgnore directives specify a space-delimited list of files and directories to ignore and exclude from the listing. Groups of files or file types may be selected via regular expressions and/or the use of wildcards. While we’re here, let’s add a few more items to our ignore list:

# IGNORE THESE FILES
IndexIgnore header.html footer.html favicon.ico .htaccess .ftpquota .DS_Store icons *.log *,v *,t .??* *~ *#

Most of these items are commonly seen in various server directories and should not be displayed along with ordinary content. Feel free to add, delete, or modify this list of ignored items to suit your specific needs. For now, let’s get on with the styling of the page.

Hopefully, most of my readers are familiar enough with CSS that styling basic things like background colors, text sizes, and other basic properties is straightforward. Some fun things to do include styling the heading element, default text, and the various link states. For our evolving /floyd/ directory, we want a nice, light-grey background, monospace font selection, and dark link color with discernible :hover and :visited states. To do this, we add the following code to the <head> region of our custom header document like so:

<html><head><title>Pink Floyd - Meddle</title>
<style type="text/css">
body {
	background: #eee;
	margin: 33px;
	color: #333;
	}
h1 {
	font: 2.0em Georgia, serif;
	}
h1 a:hover, h1 a:active {
	text-decoration: none;
	}
a:link {
	text-decoration: none;
	color: #555;
	}
a:visited {
	text-decoration: none;
	color: #777;
	}
a:hover, a:active {
	text-decoration: underline;
	color: maroon;
	}
pre {
	font: 0.9em/1.3em "Courier New", Courier;
	margin: 3px 0;
	color: #777;
	}
pre img {
	display: inline;
	}
img {
	margin: 3px 0;
	}
</style>
</head>
<body><h1><a href="http://domain.tld/mp3/floyd/" title="Pink Floyd - Meddle">Pink Floyd MP3 Collection - Meddle</a></h1>

With that in place, here is how our /floyd/ directory looks now:

“floyd” directory with applied CSS styles [full view]

Now let’s do something about those horrible default icons.

Step 6: Customizing File and Folder Icons

Apache’s mod_autoindex module provides a great amount of flexibility and customization for the icons used in “fancy indexed” directory listings. The first thing we want to do when using default icons is to specify a default icon to be used for non-specified file types:

# DEFAULT ICON
DefaultIcon icons/generic.gif

For our example directory, we want to keep all custom icons located within the directory itself, so we create a folder called “icons” and place our generic.gif and all subsequent icons inside of it. Then, to hide the new icons folder from the directory listing, we add the following term to our IndexIgnore directive:

# IGNORE THESE FILES
IndexIgnore header.html footer.html icons

Looking at the default directory view, we see that there are many different icons that may be customized, including one that is disabled by default. This “blank icon” may be customized with any icon by adding the following directive to your HTAccess file:

AddIcon icons/purple.gif ^^BLANKICON^^

..which displays a purple icon in place of the previously unseen “blank” icon:

Default hidden icon replaced by a visible icon (note left-alignment of name link)

I prefer the default, blank icon, however, so I will disable the custom icon by “commenting out” the previous directive using a pound sign ( # ):

# AddIcon icons/purple.gif ^^BLANKICON^^

Moving on to other default icons, there are two key icons that you may want to customize: the “up a level” icon and the folder icon. Custom folder icons are specified using the following directive:

AddIcon icons/grey.gif ^^DIRECTORY^^

Similarly, the “up a level” icon is associated with two dots ( .. ) in HTAccess, and may be customized like so:

AddIcon icons/green.gif ..

Likewise, individual icons may be specified in several ways. First, we may specify custom icons by matching any part of the file extension (using pattern matching). Here are some examples that we will include in our finished HTAccess file:

# SPECIFIC FILE ICONS
AddIcon icons/blue.gif .txt .pdf .zip .rar .jpg .jpeg .jpe .png .gif .mpg .ico .js .log .doc .css .html
AddIcon icons/red.gif readme
AddIcon (MP3,icons/arrow.gif) .mp3

With the first line, any of the listed file types will sport a nifty blue icon. With the second line, any files containing the character string, “readme” will feature a nice red icon. And finally, in the third line, we are associating all MP3s with a small, grey arrow. Also, the format used in the third line allows us to define the alt text used by the image element displaying our image. If the image should become unavailable for some reason, the alt text will be displayed instead.

Another way to sepcify custom icons is by type. By targeting the MIME-type of the file, we may target, say, all image files and associate them with a specific type of icon:

# CUSTOM IMAGE ICONS
AddIconByType (IMG,icons/image.gif) image/*

And finally, we may specify custom icons by encoding:

# GZIP ENCODING ICON
AddIconByEncoding (CMP,icons/compress.gif) x-compress x-gzip

With these three options for specifying custom icons, the configurational possibilities are endless. It all depends on your specific directory-listing needs. Other kewl things you can do with your custom icon play include specifying a custom height and width for your icons, and also turning your icons (custom or not) into links! To do so, add the following parameters to your IndexOptions directive:

IconHeight=16 IconWidth=16 IconsAreLinks

Although for our example, we will comment out these parameters as they are not needed. (Still with me? — Your stamina is great!) Here is how our custom /floyd/ directory looks with teh custom icons added:

“floyd” directory listing featuring custom icons [full view]

Ahh, looking much better.. Now let’s wrap things up with some custom descriptions for the various file types and subdirectories.

Step 7: Adding Descriptions to Folders and Files

Custom descriptions may also be added for any specific file, file type, or folder. Depending on your needs, descriptions may be overkill, but they are useful for providing highlighting key files and folders, explaining various items, and providing extra information in general. This list of descriptions for common file types should help you understand how to include descriptions for your own directories:

AddDescription "MPEG Layer 3 Format" .mp3
AddDescription "GZIP compressed TAR archive" .tgz .tar.gz
AddDescription "GZIP compressed archive" .Z .z .gz .zip
AddDescription "RAR compressed archive" .rar
AddDescription "TAR compressed archive" .tar
AddDescription "ZIP compressed archive" .zip 
AddDescription "Windows executable file" .exe
AddDescription "Common Gateway Interface" .cgi
AddDescription "Joint Photographics Experts Group" .jpg .jpeg .jpe
AddDescription "Graphic Interchange Format" .gif
AddDescription "Portable Network Graphic" .png
AddDescription "Vector graphic" .ps .ai .eps
AddDescription "Hypertext Markup Language" .html .shtml .htm
AddDescription "Cascading Style Sheet" .css
AddDescription "DocType Definition" .dtd
AddDescription "Extensible Markup Language" .xml
AddDescription "Win32 compressed HTML help" .chm
AddDescription "Adobe Portable Document Format" .pdf
AddDescription "Plain text file" .txt .nfo .faq .readme
AddDescription "Unix man page" .man
AddDescription "Email data" .eml .mbox
AddDescription "Microsoft Word document" .doc
AddDescription "PHP: Hypertext Preprocessor script" .php  .php3 .php4
AddDescription "PHP: Hypertext Preprocessor source code" .phps
AddDescription "Javascript" .js
AddDescription "Java code"  .java
AddDescription "Unix shell script" .sh .shar .csh .ksh .command
AddDescription "Mac OS X shell script" .command
AddDescription "Configuration file" .conf
AddDescription "Mac OS X terminal" .term
AddDescription "BitTorrent file" .torrent
AddDescription "Windows link" .lnk .url

See the pattern there? It’s a lot of fun to play around with descriptions, as there are many different things you can do with them. For example, you can actually include HTML along with your descriptions:

# FILE DESCRIPTIONS
AddDescription "<span class='description'>MPEG Layer 3 Format</span>" .mp3
AddDescription "<span class='description'>GZIP compressed TAR archive</span>" .tgz .tar.gz
AddDescription "<span class='description'>GZIP compressed archive</span>" .Z .z .gz .zip
AddDescription "<span class='description'>RAR compressed archive</span>" .rar
AddDescription "<span class='description'>TAR compressed archive</span>" .tar
AddDescription "<span class='description'>ZIP compressed archive</span>" .zip 
AddDescription "<span class='description'>Windows executable file</span>" .exe
AddDescription "<span class='description'>Common Gateway Interface</span>" .cgi
AddDescription "<span class='description'>Joint Photographics Experts Group</span>" .jpg .jpeg .jpe
AddDescription "<span class='description'>Graphic Interchange Format</span>" .gif
AddDescription "<span class='description'>Portable Network Graphic</span>" .png
AddDescription "<span class='description'>Vector graphic</span>" .ps .ai .eps
AddDescription "<span class='description'>Hypertext Markup Language</span>" .html .shtml .htm
AddDescription "<span class='description'>Cascading Style Sheet</span>" .css
AddDescription "<span class='description'>DocType Definition</span>" .dtd
AddDescription "<span class='description'>Extensible Markup Language</span>" .xml
AddDescription "<span class='description'>Win32 compressed HTML help</span>" .chm
AddDescription "<span class='description'>Adobe Portable Document Format</span>" .pdf
AddDescription "<span class='description'>Plain text file</span>" .txt .nfo .faq .readme
AddDescription "<span class='description'>Unix man page</span>" .man
AddDescription "<span class='description'>Email data</span>" .eml .mbox
AddDescription "<span class='description'>Microsoft Word document</span>" .doc
AddDescription "<span class='description'>PHP: Hypertext Preprocessor script</span>" .php  .php3 .php4
AddDescription "<span class='description'>PHP: Hypertext Preprocessor source code</span>" .phps
AddDescription "<span class='description'>Javascript</span>" .js
AddDescription "<span class='description'>Java code</span>"  .java
AddDescription "<span class='description'>Unix shell script</span>" .sh .shar .csh .ksh .command
AddDescription "<span class='description'>Mac OS X shell script</span>" .command
AddDescription "<span class='description'>Configuration file</span>" .conf
AddDescription "<span class='description'>Mac OS X terminal</span>" .term
AddDescription "<span class='description'>BitTorrent file</span>" .torrent
AddDescription "<span class='description'>Windows link</span>" .lnk .url

Then, with the classed spans in place, you can add something like the following to the CSS in your custom header.html file:

.description {
	font-style: italic;
	font-size: 90%;
	color: #777;
	}

..which would then have the following effect on our default directory listing:

“floyd” directory listing featuring styled descriptions [full view]

You may also want to add a default description for anything that you may have missed (bonus points if you call me on this!):

# DEFAULT DESCRIPTION
AddDescription "[<span class='description'>unknown item..</span>]" *

While we’re at it, let’s see how subfolders and their respective descriptions might be included within our incredible /floyd/ directory. After creating three folders, “Images”, “Lyrics”, and “Notes”, we add the following directives:

# FOLDER DESCRIPTIONS
AddDescription "[<span class='description'>Pink Floyd Images</span>]" Images
AddDescription "[<span class='description'>Pink Floyd Lyrics</span>]" Lyrics
AddDescription "[<span class='description'>Pink Floyd Notes</span>]" Notes

..which gives us this final result:

“floyd” directory listing with three subfolders and their descriptions [full view]

Alright, I can’t take any more! Let’s close this thing!!

Bonus Tips!

Tip #1 You can add the following tag the header file to make links open in a new tab/window:

<base target="_blank">

Should be placed anywhere in the head element.

Tip #2 If you can’t get the header.html file to display, try adding AddType text/html .html to your .htaccess file.

Thanks to Mike Epler for these tips!

En Closure

In this rather extensive tutorial, we have transformed a default directory listing into a completely customized, fully functional presentation of directory contents. Using nothing more than HTAccess and a little HTML & CSS, any Apache-powered directory listing is under your complete and utter control. No fancy-pants third party scripts or programming tricks required. It’s all self-contained, self-sustaining, and wonderful. Have fun with this method, and use it to transform your boring default directories into beautifully styled works of well-designed bliss. Or whatever!! I don’t care ‘cuz I am finally done with article and it’s time to chill!!!! Peace!!!

References

• Apache Module mod_autoindex — Official Manual

About the Author

Jeff Starr = Web Developer. Security Specialist. WordPress Buff.