The binding segment of the WSDL specifies how operation requests and
responses, defined in
PortType, are transmitted over the wire using
underlying transport protocols.
Binding values include HTTP GET, HTTP POST, and SOAP. SOAP is not tied to a specific transport. SMTP, FTP, and HTTP are options that can transport a SOAP request; however, HTTP is the most common.
The Product Advertising API does not support HTTP POST requests for these cart
CartModify. Use an HTTP GET request for these
The Product Advertising API uses SOAP, as shown in the following WSDL snippet.
<binding name="AWSECommerceServiceBinding" type="tns:AWSECommerceServicePortType"> ... <operation name="ItemSearch"> <soap:operation soapAction="http://soap.amazon.com" /> <input> <soap:body use="literal" /> </input> <output> <soap:body use="literal" /> </output> </operation>
This binding shows that Product Advertising API uses two SOAP extensions: soap:operation and soap:body.
The soap:operation element specifies that the Product Advertising API operation,
ItemSearch , in this case, is bound to a specific SOAP
implementation. The soapAction attribute specifies that the SOAPAction HTTP
header is used to identify the Product Advertising API service, which is the URI value of
soapAction enables Amazon web servers to determine the intent of the SOAP
request without having to examine the message portion of the SOAP payload.
Specifying this URI is required to access Product Advertising API web servers.
The soap:body element specifies the input and output details. The value in the Product Advertising API WSDL is "literal," which means that instead of encoding the input and output as a SOAP struct, a literal XML document is used. You have seen that Product Advertising API responses are XML documents.