User Authentication With patUser (part 2) - Slice And Dice (
Page 13 of 13 )
How
about one more? Once the user has been registered in the system (perhaps using a
script like the one on the previous page), it becomes possible to slice and dice
that user information for a variety of different purposes. In this next script,
different sections of a single Web page are hidden or displayed on the basis of
a user's credentials and group membership.
<?php
// include classes
include("../include/patDbc.php");
include("../include/patUser.php");
include("../include/patTemplate.php");
// initialize database layer
$db = new patMySqlDbc("localhost", "db211", "us111", "secret");
// initialize template engine
$tmpl = new patTemplate();
$tmpl->setBasedir("../templates");
// initialize patUser
$u = new patUser(true);
// connect patUser to database/template engines
$u->setAuthDbc($db);
$u->setTemplate($tmpl);
// set tables
$u->setAuthTable("users");
$u->setGroupTable("groups");
$u->setGroupRelTable("usergroups");
// check authentication
$u->requireAuthentication("displayLogin");
?>
<html>
<head>
<basefont face="Arial">
</head>
<body>
<!-- this section only displayed to authenticated users -->
<hr> You have
been authenticated. Welcome.
<!-- this section only displayed to members of the Operations group -->
<?php
// get GID for Operations group
$data = $u->getGroups(array( "gid" ),
array( array( "field" => "name",
"value" => "Operations",
"match" => "contains" ) ) );
$opsGid = $data[0]['gid'];
// check to see if user is member and display section if so
if ($u->isMemberOfGroup($u->getUid(), $opsGid))
{
?>
<hr>
Latest news from Operations: All systems up and running normally.
<?php
}
// get GID for Administration group
$data = $u->getGroups(array( "gid" ),
array( array( "field" => "name",
"value" => "Administration",
"match" => "contains" ) ) );
$adminGid = $data[0]['gid'];
// check to see if user is member of both Administration and Operations
// and display page if so
if ($u->isMemberOfGroup($u->getUid(), $opsGid) &&
$u->isMemberOfGroup($u->getUid(), $adminGid)) { ?>
<!-- this section only displayed to members of both Operations and
Administrations group --> <hr> <a href="#">Click here to modify system
configuration settings.</a>
<?php
}
?>
</body>
</html>
Most of this should be fairly easy to understand. The page is divided into
three sections, with the first one available to all authenticated users and the
remaining two turned on only if the user is a member of the appropriate groups.
The isMemberOfGroup() method discussed on the previous page is used to test
whether the user belongs to the group or not, while the the getGroups() method
is used, this time with additional selection criteria, to obtain the group ID of
the various groups involved.
Business logic similar to that above can be
used to create Web pages that are sensitive to user credentials and privileges,
and that can dynamically change so that only the appropriate information is
presented to each user. And with patUser again doing most of the work, adding
this business logic to a Web page is a snap.
And that's about it for the
moment. This article was a little longer than the previous one, but it also
covered a lot more ground. You should now have a better understanding of
patUser's concepts of users, groups and group membership, and of the user and
group management API available in the patUser library. In this article, I
demonstrated most of the important components of this API, showing you how to
list, add, edit and modify users and groups, and how to organize users into
groups. Finally, I wrapped things up with two examples of how these API calls
can be used in real-world situations: a script for administrators to add new
users via a Web-based interface, and a Web page that altered its visible content
based on the logged-in user's permissions.
In the third (and concluding)
article in this series, I will be briefly looking at a number of
hard-to-categorize-yet-very-useful methods in the patUser library. These include
methods to handle errors, track user movement, collect statistics and identify
users and groups using different criteria. Make sure you don't miss that
one!
Note: Examples are illustrative only, and are not meant for a
production environment. Melonfire provides no warranties or support for the
source code described in this article. YMMV!
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