Introduction

Installation procedure

Initial configuration

Changelog

These are some of the common questions posted on support forum.

From URL: ^/$
Request only: true (checked)

From URL: /catalog\.php\?page=1&order=asc

/catalog\.php[[.question-mark.]]page=1&order=asc

From URL: /index2\.php\?option=com_content&task=view&id=[0-9]{1,3}&pop=1&page=[0-9]{1,2}&Itemid=[0-9]{1,5}

From URL: ^/category/oldfolder/
To URL: {scheme}://{siteurl}/category/newfolder/{pathltrim /category/oldfolder/}{queryfull}
Request only: true (checked)

In this paragraph we will explain the meaning of each plugin parameter. To edit plugin settings go to menu "Extensions" -> "Plug-in Manager", find "System - ReDJ Community" or "System - ReDJ Enterprise" in the list and click on it to access to configuration page.

Basic Plugin Parameters

In the following table there’s a list of all basic plugin parameters.

Advanced Plugin Parameters

In the following table there’s a list of all advanced plugin parameters.

This feature allows to record all the referers for site visitors. A trace log with all referers is available, and this can be useful to identify traffic sources for the web site.

For any referer item in the list the following fields are available:

About the available buttons:

Purge button will delete all entries.

Delete button will delete only selected entries.

Reset stats will just reset all statistics (hits and last visit).

Beware that this feature must be activated with a corresponding option in the plugin settings. See paragraph “ Plugin settings” for more details.

With this function it is possible to record all errors that the site receives. This provide a kind of trace log for error requests, and can be useful to identify dead backlinks that need to be redirected elsewhere. Analyzing requests it is also possible to extract other useful information (e.g. to detect if the site is subject to hacker attacks like remote file inclusion or sql injection).

For any error item recorded the following fields are available:

About the available buttons:

Purge button will delete all entries.

Delete button will delete only selected entries.

Reset stats will just reset all statistics (hits and last visit).

Beware that this feature must be activated with a corresponding option in the plugin settings. See paragraph “ Plugin settings” for more details.

ReDJ allows to create a custom error page that can replace the Joomla standard one. To manage error pages go to menu "Components" -> "ReDJ" -> "Pages 404".

There are always two predefined pages as default, with titles "Italiano" (ID = 1) and "English" (ID = 2). These are example pages, added just to show how to create HTML for a custom error page. Specifically, these pages are identical to Joomla standard error page, except they add the email address of site Administrator, showing how to use supported macros.

BEWARE: do NOT customize these pages, because these are deleted and recreated on each ReDJ upgrade, so any changes will be lost. It’s better to add a new page (ID > 2) and use this.

For any custom error page the following fields are available:

Once a custom error page was created, it can be enabled in ReDJ system plugin. Select menu "Extensions" -> "Plug-in Manager" and open plugin "System - ReDJ Community" or "System - ReDJ Enterprise". Under "Basic Options" set "Custom page 404" to yes and select the page to use from the drop-down list. See paragraph "Plugin settings" for more details.

Referring to an URL like the following:

Here is a list of supported macros for destination "To URL" field:

As mentioned earlier the "From URL" field can contain a regular expression and can match the whole URL or just a part of it. The following table shows some regexp examples.

The rules ordering is important for matching the source URL. For each URL request, all published rules are compared according to their ordering. Even if two or more rules match, ONLY THE FIRST ONE in the rule ordering will be used. This can be useful, as example, to distinguish a category from its articles. If we have two URLs as follow:

http://www.mysite.com/category/
http://www.mysite.com/category/article-1.html

Rules could be configured with the following "From URL" field:

For http://www.mysite.com/category/article-1.html both rules match this URL, but only the first matching rule is applied so, if rules are configured in the wrong order, the redirect for page article-1.html will never be used.

Internal Redirect

This feature is available only in the Enterprise version of ReDJ. The 301 (Moved Permanently) or 307 (Temporary Redirect) redirects are client-side redirects. The user from his web browser requests a page (the source URL), and the web server responds with the address to which the page was moved (the destination URL). At this point, it is the client browser that makes a new request for the new address (i.e. is the client that performs the redirect).
With the "Internal Redirect" instead, is the web server that changes the page returned to web browser with the new destination. The result is a server-side redirect (i.e. the redirect happens "internally" to Joomla), and the user does not notice any URL change in the address bar. This is a great solution to create URL aliases and short URLs. Just as example, let's consider an existing URL like the following:

http://www.yoursite.com/index.php/component/reservation/event/4/forum

It is possible to create a rule with a redirection type 200 (Internal) that match to the following URL:

http://www.yoursite.com/training

The page content sent to client is exactly the same for both URLs, but the shortest URL is much friendly and better for SEF and SEO.

Dynamic Destinations (Macros and Placeholders)

Let's take a deeper look at "To URL" destination field. Since version 1.5 of ReDJ, a support for complex "macros" has been added, and this allows to create dynamic destinations. The version 1.7.1 introduces support for "placeholders", that adds a new dimension to build complex URL transformations.

When the URL request matches the "From URL" source field of a rule, if the destination field "To URL" contains one or more macros or placeholders, then ReDJ first calculates and replaces any placeholder and macro with its current value, builds the final "real destination" URL, and finally performs the redirect.

Macros allow, as example, to manipulate pieces of the current matching URL (e.g. a query variable), placeholders can define new variables using constant strings, macros and other (previous) placeholders, so both let you to create dynamic destinations as complex transformations of the current source URL.

Here a practical example of dynamic destinations and macro substitution:

Placeholders allow you to define a set of values where each value is associated and identified by a name. A placeholder can be used in the definition of other placeholders or in the definition of meta info (practically they are based on the same principle of the variables in programming languages). Syntax for defining a placeholder is name=value where 'name' is the placeholder identifier (placeholder valid name, like variables in PHP convention, starts with a letter or underscore, followed by any number of letters, numbers, or underscores), while 'value' can be any string, and can also contains macros or placeholders defined before, and both will be replaced with their current value. The syntax to use a placeholder is ${name}, where 'name' is the name of the placeholder. Each rule has a text area field to define any number of placeholders, one for each row. For example, if you enter:

a=this
b=${a} is
c=${b} an
d=${c} example

Putting the placeholder ${d} in a meta field (e.g. title or description), this field will assume the value 'this is an example'. Here is a practical example of how to use the placeholders to get a complex result through the use of available macros in a sequence of definitions. Let's assume we need to create a rule for URL:

http://www.mysite.com/index.php?option=com_content&view=article&id=53&Itemid=280

We want to withdraw the article id (53), and perform a look-up on the database for getting the article alias (using-joomla), to be used for example in the page title. We can define the following placeholders:

id={preg_match 1}/option=com_content&view=article&id=([0-9]+)/i{/preg_match}
alias={tableselect #__content,alias,id}${id}{/tableselect}

After this, putting ${alias} in the title field, this will be replaced by 'using-joomla' in the page.

To create a redirection rule go to menu "Components" -> "ReDJ" –> "Redirects", and click on “New” button. A form will be shown to entering redirection information related to the rule.

The "From URL" field must contains an "URL part" to match with any requested URL. If "Request only" is checked, then URL parts "scheme", "user", "pass", "host" and "port" will be ignored, otherwise the full requested URL will be checked. It is also possible to use Regular Expressions in "From URL" field. ReDJ supports regular expressions according to Henry Spencer's implementation:

http://dev.mysql.com/doc/refman/5.0/en/regexp.html

This option makes it possible to create complex patterns to match a bunch of URLs to redirect with just a single redirection rule.

The field "To URL" must contains the destination URL where to redirect the web browser for any requested URL that matches with the current rule. It must specify an absolute URL, starting with the "scheme" part. The "To URL" field can contains macros and placeholders to build the destination dynamically. Each macro or placeholder is evaluated after an URL matches, and its value is replaced to the macro or placeholder itself. Support of regular expressions, macros and placeholders allow to build complex URL trasformations.

The field "Skip" is optional. Like "From URL" it can contains an "URL part" and supports regular expressions, but its purpose is just the opposite. It allows to specify a condition to skip the rule and its redirect when the condition is satisfied.

The field "Skip user groups" works only for ReDJ Enterprise, and allows to select one or more user groups which skip the rule (i.e. the redirection will not be applied).

The "Redirect" field indicates the redirection type to use. There are three options available:

• 301 (Moved Permanently)
• 307 (Temporary Redirect)
• 200 (Internal Redirect)

The Internal Redirect option is available only for ReDJ Enterprise, and allows to change the destination page returned to web browser "internally" to Joomla, on the server side. This means that the user stays on the same URL and cannot notice any changes in the address bar. The Internal Redirect option can be selected also in ReDJ Community, but in this case a standard 301 redirect will be used instead.

About the meanings of other fields:

• Case sensitive: specifies if the match between "From URL" and the requested URL must consider the letters case (i.e. uppercase and lowercase are considered different). If case sensitive is checked, the rule must match with requested URL also for case of characters. If case sensitive is unchecked, no matter if rule and requested URL differ only for case of characters (i.e. MyPage.php = myPage.PHP = mypage.php).
• Request only: as stated before, this field is used to specify if only the request part or the whole URL must be considered of the requested URL.
• Decode URL: the requested URLs come on the server always encoded (i.e. special chars are replaced by % chars). If this field is unchecked the URL is compared with the rule as is. If the field is checked, the requested URL is first decoded and then checked if matches with the rule.
• Placeholders: can contains a list of placehoders (one per row). A placeholder is like a variable that can assume a value based on any string, macros and other placeholders (defined before).
• Comment: allows to add a memo note to each redirection rule.

The statistics fields provide useful information about rule usage. The "Hits" counts the number of times the rule were used, and the "Last visit" indicates the last time the rule were applied.

In the example showed in the image above, the source and the destination are:

From URL: ^/test.html
To URL: http://{siteurl}/

With this settings all the following URLs will be redirected:

http://www.mysite.com/test.html

http://www.mysite.com/test.html?param=xxx

http://www.mysite.com/test_html

While this will not be:

http://www.mysite.com/directory/test.html

This is because in the regular expression ^/test.html the initial caret ^ means "start with", and "request only" is checked, so /directory/test.html will not match. Notice that the URL with /test_html also matches, because the dot means "any char" in the regexp syntax. To specify a literal dot, this should be escaped with \, so the rule should be:

From URL: ^/test\.html

This will match only the first and the second URL of our previous example, but not the third (http://www.mysite.com/test_html).

The destination contains an example of macro, {siteurl}, which will be replaced with www.mysite.com.