This is a library for creating documents in the application/hal+json and application/hal+xml hypermedia formats
It requires PHP 5.4 or later.
<?php
require_once 'vendor/autoload.php';
use Nocarrier\Hal;
$hal = new Hal('/orders');
$hal->addLink('next', '/orders?page=2');
$hal->addLink('search', '/orders?id={order_id}');
$resource = new Hal(
'/orders/123',
array(
'total' => 30.00,
'currency' => 'USD',
)
);
$resource->addLink('customer', '/customer/bob', array('title' => 'Bob Jones <[email protected]>'));
$hal->addResource('order', $resource);
echo $hal->asJson();
echo $hal->asXml();The preferred method of installation is via packagist as this provides the PSR-0 autoloader functionality. The following command will download and install the latest version of the Hal library into your project.
php composer.phar require nocarrier/hal
Alternatively, clone the project and install into your project manually.
Nocarrier\Hal is licensed under the MIT license.
A Hal resource can be created with no values set:
$hal = new \Nocarrier\Hal();with a URI for the resource:
$hal = new \Nocarrier\Hal('/orders');and also with an array of data:
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);Hal resources can also be created from existing XML or JSON documents:
$hal = \Nocarrier\Hal::fromJson($jsonString);$hal = \Nocarrier\Hal::fromXml($xmlString);$hal = \Nocarrier\Hal::fromXml($simpleXMLElement);The depth of embedded resources parsed with both these methods is controlled by a second argument, which defaults to 0:
$hal = \Nocarrier\Hal::fromJson($jsonString, 5);The Hal resource can be formatted as JSON or XML:
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);
$hal->asJson();which with a first argument of true for pretty printing:
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);
$hal->asJson(true);gives:
{
"customerId": "CUS1234",
"_links": {
"self": {"href": "/orders"}
}
}and
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);
$hal->asXml(true);gives:
<?xml version="1.0"?>
<resource href="/orders">
<customerId>CUS1234</customerId>
</resource>The data can be set through setData and read with getData:
$hal = new \Nocarrier\Hal('/orders');
$hal->setData(['customerId' => 'CUS1234']);
$hal->getData();Using array keys in the data for the XML representation can be done by
prefixing the key with @:
$hal = new \Nocarrier\Hal('/orders');
$hal->setData(['customerId' => ['CUS1234', '@type' => 'legacy']]);gives:
<?xml version="1.0"?>
<resource href="/orders">
<customerId value="CUS1234" type="legacy"/>
</resource>The @ is ignored if JSON is rendered:
{
"customerId": {
"value": "CUS1234",
"type":" legacy"
},
"_links": {
"self": {"href": "/orders"}
}
}Links can be added to the resource by providing the rel identifying them and a URI:
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);
$hal->addLink('next', '/orders?page=2');
$hal->addLink('search', '/orders?id={order_id}');gives:
{
"customerId": "CUS1234",
"_links": {
"self": {
"href": "/orders"
},
"next": {
"href": "/orders?page=2"
},
"search": {
"href": "/orders?id={order_id}"
}
}
}If a Hal object has been created from a response returned from elsewhere it can be helpful to retrieve the links from it.
$json = '{
"customerId": "CUS1234",
"_links": {
"self": {
"href": "/orders"
},
"next": {
"href": "/orders?page=2"
},
"search": {
"href": "/orders?id={order_id}"
}
}
}';
$hal = \Nocarrier\Hal::fromJson($json);
foreach($hal->getLinks() as $rel => $links) {
echo $rel."\n";
foreach($links as $link) {
echo (string) $link."\n";
}
}next
/orders?page=2
search
/orders?id={order_id}
and
$json = '{
"customerId": "CUS1234",
"_links": {
"self": {
"href": "/orders"
},
"next": {
"href": "/orders?page=2"
},
"search": {
"href": "/orders?id={order_id}"
}
}
}';
$hal = \Nocarrier\Hal::fromJson($json);
foreach($hal->getLink('next') as $link) {
echo (string) $link."\n";
}outputs:
/orders?page=2
As well as linking to resources so that the client can fetch them they can be directly embedded in the resource.
$hal = new \Nocarrier\Hal('/orders', ['customerId' => 'CUS1234']);
$resource = new \Nocarrier\Hal(
'/orders/123',
array(
'total' => 30.00,
'currency' => 'USD',
)
);
$resource->addLink('customer', '/customer/bob', array('title' => 'Bob Jones <[email protected]>'));
$hal->addResource('order', $resource);outputs:
{
"customerId": "CUS1234",
"_links": {
"self": {
"href": "/orders"
}
},
"_embedded": {
"order": [
{
"total": 30,
"currency": "USD",
"_links": {
"self": {
"href": "/orders/123"
},
"customer": {
"href": "/customer/bob",
"title": "Bob Jones <[email protected]>"
}
}
}
]
}
}