For that I use the Amazon Client Demo hosted in the PHP Web Services Demo Site. With this demo you can do shopping with Amazon using their web services API. It uses a php library (AmazonClient.php) that allows us to connect Amazon using SOAP or REST libraries.

You can see in the library code It is using different values for “useSOAP” argument depending on what form of messaging we like to use. Amazon SOAP service uses the SOAP 1.1 and the REST service uses the “GET” HTTP method for messaging. We can configure these details as mentioned in the following table.

array(
      "to"=>self::AMAZON_REST_ENDPOINT,
      "HTTPMethod"=>"GET",
      "useSOAP" => FALSE)

array(
      "to"=>self::AMAZON_SOAP_ENDPOINT,
      "useSOAP" => "1.1",
      "action" => "http://soap.amazon.com")

Since Amazon requires different request messages for SOAP and REST services, we have to create them separately depending on the request type. But the response returns by the service is same in both cases so we can handle it using the same code.

Here is how ItemLookup operation of the Amazon service is written within the above mentioned constrains.

    /**
     * ItemLookup
     * @param $ASIN Amaxon Item Id
     * @return associate array consist of the response parameters
     */
    public function ItemLookup($ASIN)
    {

        if($this->is_soap)
        {
             $req_payload = <<<XML
                <ItemLookup xmlns="http://webservices.amazon.com/AWSECommerceService/2007-10-29">
                    <SubscriptionId>{$this->amazon_key}</SubscriptionId>
                    <ResponseGroup>Medium</ResponseGroup>
                    <Request>
                        <ItemId>{$ASIN}</ItemId>
                        <ReviewPage>1</ReviewPage>
                    </Request>
                </ItemLookup>
XML;
        }
        else
        {
             $req_payload = <<<XML
                <ItemLookup xmlns="http://webservices.amazon.com/AWSECommerceService/2007-10-29">
                    <SubscriptionId>{$this->amazon_key}</SubscriptionId>
                    <Service>AWSECommerceService</Service>
                    <ResponseGroup>Large</ResponseGroup>
                    <Operation>ItemLookup</Operation>
                    <ItemId>{$ASIN}</ItemId>
                    <ReviewPage>1</ReviewPage>
                </ItemLookup>
XML;
        }

        $ret_message = $this->request($req_payload);

        $simplexml = new SimpleXMLElement($ret_message->str);

        $res = $simplexml;

        return $res;
    }

Here we take a scenario of submitting applications (say for a school).

In RESTful world we map a resource to a unique URL. In this demo, application is a resource. We use the URL “application/{id}” to represent a particular application with the id {id}.

You can  use  HTTP verb + Resource URL touples to manipulate the resource with CRUD operations.  Here is how it is done in this particular demonstration.

Go for the wsf/php demo sitefor the live demo of this service. Visit the demo service source code to see how easy to implement it with WSF/PHP Data Services library.

I wrote a similar blog on Data Services last week to demonstrate how you design the mapping of url to different resources in a RESTful Service.

With the addition of all these HTTP verbs WSO2 WSF/PHP 2.0.0 become a great tool for RESTful developers. Specially with the introducing Data Services library it was so easy to make your database a REST service. I m thinking of preparing a series of application to demonstrate the power of WSF/PHP with all these new features.

This demo -RESTful School- shows how you map a URL to a peice of data. Here we use only the http “GET” method (which is the most to used in practicle data service).

Here is some description of the operations you find in there. Just check the source code for RESTful School demo to see how this is done in code level.

subjects

SELECT subjectName, subjectTeacher FROM Subjects

subjects/{name}

SELECT subjectName, subjectTeacher FROM Subjects where SubjectName = ?

students

SELECT * FROM Students

students/{name}

SELECT subjectName, marks FROM Marks m, Subjects s ".
        " where m.studentId = ? and m.subjectID = s.subjectId

SELECT * FROM Students where StudentName = ?

students/{student}/marks/{subject}

SELECT marks FROM Marks, Subjects, Students where StudentName = ?".
        " and SubjectName = ? and Marks.subjectId = Subjects.subjectId".
        " and Marks.studentID = Students.StudentId;