Page Guard Redirect

Description

Page Guard Redirect uses a single URL parameter or POST variable as a means of providing a token to guard access to any page on which this plugin’s shortcode is placed – redirection can be made to occur when the token fails to match what is expected (the alternative, i.e. redirect when token DOES match – is also included for completeness.)

The shortcode to use is ‘pgredirect’ – its attributes are:

tokenparam (required): a string value containing the name of the token URL param - e.g. 'mytoken'
tokenvalue (required): a string value containing the expected value of the tokenparam - e.g. 'x34ggj45b'
redirectURL (required): a string value containing the URL to redirect to (you can use an existing page as the target for the redirection - alternatively, for many configurations, setting this to a non existent page will make WordPress redirect to the default 404 "not found" page.)
redirectWhen (optional): -> when = "1", redirects when match is found, otherwise defaults to redirect on non-match

Syntax examples:

  redirect on non match (default) -
    [pgredirect tokenparam="mytoken" tokenvalue="1234abcd" redirecturl="http://my.redirurl.com/notfound" /]

  redirect on match (add redirectwhen="1" as an attribute) -
    [pgredirect tokenparam="mytoken" tokenvalue="1234abcd" redirectwhen="1" redirecturl="http://my.redirurl.com/notfound" /]

Usage

A typical use scenario might be to prevent access to a downloads page. Suppose you have a PayPal “Buy Now” button on your site which allows visitors to make a payment for say, an eBook or audio recording. When setting up the button in your PayPal account you specify a URL on your site to which the visitor is returned after they’ve made payment. On this return page you’ve added a link the visitor can use to download their purchase – however, you don’t want any non paying visitors to find the return page by chance!

Add a parameter to the end of the return URL (using any name and value you want) when you set up your button in PayPal e.g.

"http://your.wordpress.site/download/?dltoken=Xc345Fd77"

Next, add a pgredirect short code to your return page in WordPress –

[pgredirect tokenparam="dltoken" tokenvalue="Xc345Fd77" redirecturl="http://your.wordpress.site/notfound" /]

This will cause a redirect if Page Guard Redirect detects either the lack of the expected token in the URL parameter, or a value which doesn’t match the one in the short code’s tokenvalue attribute.