/**
* Generates a pagination URL based on a cursor.
*
* @param string $direction The direction of the page: next|previous
*
* @return string|null
*
* @throws FacebookSDKException
*/
public function getPaginationUrl($direction)
{
$this->validateForPagination();
// Do we have a paging URL?
if (isset($this->metaData['paging'][$direction])) {
// Graph returns the full URL with all the original params.
// We just want the endpoint though.
$pageUrl = $this->metaData['paging'][$direction];
return FacebookUrlManipulator::baseGraphUrlEndpoint($pageUrl);
}
// Do we have a cursor to work with?
$cursorDirection = $direction === 'next' ? 'after' : 'before';
$cursor = $this->getCursor($cursorDirection);
if (!$cursor) {
return null;
}
// If we don't know the ID of the parent node, this ain't gonna work.
if (!$this->parentEdgeEndpoint) {
return null;
}
// We have the parent node ID, paging cursor & original request.
// These were the ingredients chosen to create the perfect little URL.
$pageUrl = $this->parentEdgeEndpoint . '?' . $cursorDirection . '=' . urlencode($cursor);
// Pull in the original params
$originalUrl = $this->request->getUrl();
$pageUrl = FacebookUrlManipulator::mergeUrlParams($originalUrl, $pageUrl);
return FacebookUrlManipulator::forceSlashPrefix($pageUrl);
}
/**
* @dataProvider provideMergableEndpoints
*/
public function testParamsCanBeMergedOntoUrlProperly($urlOne, $urlTwo, $expected)
{
$result = FacebookUrlManipulator::mergeUrlParams($urlOne, $urlTwo);
$this->assertEquals($result, $expected);
}
