This is a small standalone PHP library that helps with parsing and creating Link header contents with rel="" attributes
as it is used in the context of RESTful web services.
It is a tolerant parser, silently accepting invalid input. You can use the API functions to check if a given rel exists.
The preferred way to install library is through composer.
Either run
composer require graviton/link-header-rel-parser
or add
"graviton/link-header-rel-parser": "*",to the require section of your composer.json.
Parsing an existing header is easy, just pass the plain header contents to the static function:
$header = '<http://localhost/service/self>; rel="self", '<http://localhost/service/next>; rel="next"';
$linkHeader = LinkHeader::fromString($header);
$selfUrl = $linkHeader->getRel('self')->getUri(); // will output 'http://localhost/service/self'If you are using Symfony, just fetch the Link header from the Request or Response object and pass it to the library.
You can create header contents programmatically:
$header = new LinkHeader();
$header->add(new LinkHeaderItem('http://localhost?limit(10,10)', 'self'));
$header->add(new LinkHeaderItem('http://localhost?limit(10,30)', 'next'));
$header->add(new LinkHeaderItem('http://localhost?limit(10,0)', 'prev'));
echo (string) $header;Will produce
<http://localhost?limit(10,10)>; rel="self", <http://localhost?limit(10,30)>; rel="next", <http://localhost?limit(10,0)>; rel="prev"
Combining both methods above, you can also parse existing headers, manipulate them and render them.
$header = '<http://localhost/service/self>; rel="self", '<http://localhost/service/next>; rel="next"';
$linkHeader = LinkHeader::fromString($header);
$linkHeader->add(new LinkHeaderItem('http://localhost?limit(10,10)', 'prev'));
$linkHeader->removeRel('next');
$header->getRel('self')->setUri('http://newhost');
echo (string) $header;Will produce
<http://newhost>; rel="self", <http://localhost?limit(10,10)>; rel="prev"