SOAP Interface

Summary
SOAP is an advanced and well-supported interface to Webservices.nl.
<WSDL> files define ‘style’ and ‘use’ attributes for each operation.

SOAP Introduction

SOAP is an advanced and well-supported interface to Webservices.nl.

Most programming environments support the SOAP protocol, allowing to call SOAP methods as it it were just ordinary methods.  The advanced XML protocol is hidden from the developer, making this one of the easiest interfaces to implement.

Webservices.nl offers a few different kinds of SOAP interfaces:

SOAP Document/Literal Recommended, modern version of SOAP.  The document/literal interface is WS-I compliant and supported by most libraries.
SOAP RPC/Encoded Older version.
SOAP headerless Does not use SOAP headers for authentication.

Differences between SOAP interfaces

<WSDL> files define ‘style’ and ‘use’ attributes for each operation.  These attributes determine what the SOAP XML messages for an operation look like.  The most common combinations of style and use are Document/Literal and RPC/Encoded.  To help improve interoperability between different SOAP implementations, the Webservices Interoperability Organization has created the Basic Profile, which is a series of additional requirements and specifications.  The Basic Profile requires the use of Document/Literal style.  Easier message validation and more compact XML messages are some of the benefits of this style, compared to RPC/Encoded.

All our services offered using the SOAP Document/Literal interface are compliant with the WS-I Basic Profile 1.0.

The SOAP headerless interface uses the same protocol as the RPC/Encoded interface, but makes it possible to use the SOAP interface without using SOAP headers.  To call one of the webservices methods, you need to be authenticated.  With the other SOAP interfaces, this is done using a SOAP header, which contains either a session token or a username and password.  Some clients, however, do not support sending SOAP headers.  The headerless SOAP interface makes it possible to use SOAP, without using SOAP headers.  Authentication is done by sending extra parameters.