# Module mod_usertrack

This module uses cookies to provide for a clickstream log of user activity on a site.

Status: Extension
Source File: mod_usertrack.c
Module Identifier: usertrack_module
Compatibility: Known as mod_cookies prior to Apache 1.3.

## Summary

Previous releases of Apache have included a module which generates a 'clickstream' log of user activity on a site using cookies. This was called the "cookies" module, mod_cookies. In Apache 1.2 and later this module has been renamed the "user tracking" module, mod_usertrack. This module has been simplified and new directives added.

## Directives

- CookieExpires
- CookieName
- CookieTracking

## Logging

Previously, the cookies module (now the user tracking module) did its own logging, using the `CookieLog` directive. In this release, this module does no logging at all. Instead, a configurable log format file should be used to log user click-streams. This is possible because the logging module allows multiple log files. The cookie itself is logged by using the text `%{cookie}n` in the log file format. For example:

    CustomLog logs/clickstream "%{cookie}n %r %t"

For backward compatibility the configurable log module implements the old `CookieLog` directive, but this should be upgraded to the above `CustomLog` directive.

## 2-digit or 4-digit dates for cookies?

(the following is from message <022701bda43d$9d32bbb0$1201a8c0@christian.office.sane.com> in the new-httpd archives)

    From: "Christian Allen" <christian@sane.com>
    Subject: Re: Apache Y2K bug in mod_usertrack.c
    Date: Tue, 30 Jun 1998 11:41:56 -0400

    Did some work with cookies and dug up some info that might be useful.

    True, Netscape claims that the correct format NOW is four digit dates, and
    four digit dates do in fact work... for Netscape 4.x (Communicator), that
    is.  However, 3.x and below do NOT accept them.  It seems that Netscape
    originally had a 2-digit standard, and then with all of the Y2K hype and
    probably a few complaints, changed to a four digit date for Communicator.
    Fortunately, 4.x also understands the 2-digit format, and so the best way to
    ensure that your expiration date is legible to the client's browser is to
    use 2-digit dates.

    However, this does not limit expiration dates to the year 2000; if you use
    an expiration year of "13", for example, it is interpreted as 2013, NOT
    1913!  In fact, you can use an expiration year of up to "37", and it will be
    understood as "2037" by both MSIE and Netscape versions 3.x and up (not sure
    about versions previous to those).  Not sure why Netscape used that
    particular year as its cut-off point, but my guess is that it was in respect
    to UNIX's 2038 problem.  Netscape/MSIE 4.x seem to be able to understand
    2-digit years beyond that, at least until "50" for sure (I think they
    understand up until about "70", but not for sure).

    Summary:  Mozilla 3.x and up understands two digit dates up until "37"
    (2037).  Mozilla 4.x understands up until at least "50" (2050) in 2-digit
    form, but also understands 4-digit years, which can probably reach up until
    9999.  Your best bet for sending a long-life cookie is to send it for some
    time late in the year "37".

## CookieExpires directive

Syntax: CookieExpires expiry-period
Context: server config, virtual host
Status: optional
Module: mod_usertrack

When used, this directive sets an expiry time on the cookie generated by the usertrack module. The expiry-period can be given either as a number of seconds, or in the format such as "2 weeks 3 days 7 hours". Valid denominations are: years, months, weeks, hours, minutes and seconds. If the expiry time is in any format other than one number indicating the number of seconds, it must be enclosed by double quotes.

If this directive is not used, cookies last only for the current browser session.

## CookieName directive

Syntax: CookieName token
Default: Apache
Context: server config, virtual host, directory, .htaccess
Status: optional
Module: mod_usertrack
Compatibility: Apache 1.3.7 and later

This directive allows you to change the name of the cookie this module uses for its tracking purposes. By default the cookie is named "`Apache`".

You must specify a valid cookie name; results are unpredictable if you use a name containing unusual characters. Valid characters include A-Z, a-z, 0-9, "_", and "-".

## CookieTracking directive

Syntax: CookieTracking on|off
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: optional
Module: mod_usertrack

When the user track module is compiled in, and "CookieTracking on" is set, Apache will start sending a user-tracking cookie for all new requests. This directive can be used to turn this behavior on or off on a per-server or per-directory basis. By default, compiling mod_usertrack will not activate cookies.