Display DataObjects in an SEO friendly way

Regarding this 'Need to know' tutorial from Aram, I would like to extend this principle by explaining how to display DataObjects in a SEO friendly way.

There are several ways to do this. I will explain one I prefer the most, by using SiteTree::GenerateURLSegment();.

First step is to add an extra field to the Database called URLSegment. If you use Aram's files in his tutorial on displaying DataObjects, your StaffMember $db array will look like this:

mysite/code/StaffMember.php
class StaffMember extends Page{ static $db = array( 'Name' => 'Varchar(255)', 'Description' => 'Text', 'URLSegment' => 'Varchar(255)' ); . . . . }

To add the URLSegment on save automatically, add the onBeforeWrite() method to the StaffMember class:

mysite/code/StaffMember.php
class StaffMember extends Page{ . . . . public function onBeforeWrite(){ if($this->Name){ $this->URLSegment = SiteTree::GenerateURLSegment($this->Name); if($object = DataObject::get_one($this->ClassName, "URLSegment='".$this->URLSegment."' AND ID !=".$this->ID)){ $this->URLSegment = $this->URLSegment.'-'.$this->ID; } } else { $this->URLSegment = SiteTree::GenerateURLSegment($this->ClassName.'-'.$this->ID); } parent::onBeforeWrite(); } }

First we check for a Name to generate the URLSegment. If present, probably it is, we use SiteTree::GenerateURLSegment(); to create the pretty URL. To prevent duplicate urls, we check for a DataObject by getting a StaffMember with the newly created URLSegment and set an extra filter, so it is not getting itself by adding ID !="This->ID". In this case I only want to know if there is one, and if so I just add the ID to the URLSegment, which is always unique.

This is slightly different then the SiteTree::onBeforeWrite() handles the URLSegment, which counts for the same PageTitles. I prefer to keep it simple by adding the unique ID in case the URLSegment already exist.
And finally, just in case when no Name is entered, we create an unique URLSegment, by using the ClassName and ID.

The Next step is to change the StaffMember links in the StaffSideBar.ss file by replacing {$ID} to {$URLSegment} .

The last step is to change the function getIndividualStaffMember() in StaffPage_Controller:

mysite/code/StaffPage.php
class StaffPage_Controller extends Page_Controller{ public function getIndividualStaffMember(){ if($URLAction = Director::URLParam('Action')){ $StaffMemberURLSegment = Convert::raw2xml($URLAction); if($StaffMemberURLSegment ){ return DataObject::get_one('StaffMember', "URLSegment='".$StaffMemberURLSegment."'"); } } } }

Instead of getting the DataObject by id, we simply use DataObject::get_one() and filter by URLSegment.

What about searchengines and old urls?
There is one thing you have to keep in mind. The SiteTree is versioned. This means that when a page URLSegment is changed, and old page urls are accessed, Silverstripe will redirect the visitor with a 301 Permanently Moved header to the new page url. This is not the case when using my method on getting DataObjects by URLSegment. Each time the Name is changed, the URLSegment will change too, and this will cause old links become inaccessible!

Use a 301 redirect
One way to solve this issue, is to just get the StaffMember by id and attach the URLSegment to the StaffMember link :  /{$ID}/{$URLSegment} .

Your getIndividualStaffMember function in StaffPage_controller will then look like this :

mysite/code/StaffPage.php
public function getIndividualStaffMember(){ if($URLAction = Director::URLParam('Action')){ $StaffMemberID = Convert::raw2xml($URLAction); if(is_numeric($StaffMemberID )){ $object = DataObject::get_by_id('StaffMember', $StaffMemberID); if($object->URLSegment != '' && $object->URLSegment != Director::URLParam('ID')){ Director::redirect($this->URLSegment.'/'.$object->ID.'/'.$object->URLSegment,301); } else { return $object; } } } }

Here we still get the StaffMember by ID, but we add a check if the URLSegment from the StaffMember is the same as the URLSegment in the link. The URLSegment is defined Director::URLParam('ID') .  If the URLSegment is not the same, we will use Director::redirect() to redirect to the new URLSegment with a 301 permanently moved header. This is important, so search engines will know the url is changed and the 'page' is moved.

Of course you could switch the $ID and $URLSegment, so you move the less important number to the end of the url. In the getIndividualStaffMember function you just switch Director::URLParam('Action') and Director::URLParam('ID') .

Combine ID and URLSegment
If you don't want to use 2 URLParams, you could combine the ID and the URLSegment. To do this add a function URL() to the StaffMember DataObject:

mysite/code/Staffmember.php
public function URL(){ return $this->ID.'-'.$this->URLSegment; }

In StaffSidebar.ss replace {$ID} with {$URL} to display the combined URL. () you could also skip the function and use {$ID}-{$URLSegment} instead.

Use this function in StaffPage_Controller to get the Member:

mysite/code/StaffPage.php
public function getIndividualStaffMember(){ if($URLAction = Director::URLParam('Action')){ $StaffMemberID = Convert::raw2xml($URLAction); $pos = strpos($StaffMemberID, '-'); $ID = substr($StaffMemberID, 0,$pos); $URLSegment = substr($StaffMemberID, $pos + 1); if(is_numeric($ID )){ $object = DataObject::get_by_id('StaffMember', $ID); if($object->URLSegment != '' && $object->URLSegment != $URLSegment){ Director::redirect($this->URLSegment.'/'.$object->ID.'/'.$object->URLSegment,301); } else { return $object; } } } }

We use strpos() to get the first position of - and use substr() to split the URL to the $ID and $URLSegment.

Now, this tutorial got a little longer then I expected when I started to write it. This should give you some methods to use pretty urls to display DataObjects on a Page. Maybe next tutorial should be 'How to add Versioning to DataObjects' to access DataObjects by URLSegment without the use of $ID and with 301 redirects!

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