Protocols 

Use

With protocols, you can use additional runtime services. The different runtimes support different protocols.

Integration

The runtime provides protocols through classes that implement an ABAP Objects interface. You access these protocol classes differently, depending on whether the proxy is a client or server proxy (see below).

Naming Conventions

All protocol classes have the following attributes:

●      They implement an ABAP Objects interface and include the interface IF_WSPROTOCOL.

●      They always start with the prefix IF_WSPROTOCOL.

●      For each protocol class there is a constant in the interface attributes of IF_WSPROTOCOL.

●      The name of the implemented ABAP Objects interface comprises the prefix and the constant from the interface attributes.

Example

Protocol Constant in IF_WSPROTOCOL	Corresponding Interface for the Protocol Classes
PAYLOAD	IF_WSPROTOCOL_PAYLOAD

To access the protocol in this example, use the protocol constant IF_WSPROTOCOL=>PAYLOAD. For an overview of all protocol classes, see the Features section of this documentation.

Accessing Protocol Classes for Consumer Proxies

With consumer proxies, you access the protocol class using their method GET_PROTOCOL . Below is an example of the IF_WSPROTOCOL_PAYLOAD protocol:

DATA:
lo_clientProxy      TYPE REF TO co_clientProxy,
lo_payload_protocol TYPE REF TO if_wsprotocol_payload
lo_payload          TYPE REF TO if_ws_payload.

CREATE OBJECT lo_clientProxy.

* Get Protocol Class Using Method GET_PROTOCOL

lo_payload_protocol ?=
       lo_clientProxy->get_protocol( if_wsprotocol=>payload ).

CALL METHOD lo_clientProxy->execute_synchronous
            EXPORTING output  = ls_request
            IMPORTING input   = ls_response.

* Use Protocol Methods

lo_payload = lo_payload->get_sent_request_payload( ).

Accessing Protocol Classes for Provider Proxies

Within the implementation of a provider proxy, you get the protocol class by using the CL_PROXY_ACCESS=>GET_SERVER_CONTEXT( ) method:

DATA:  lo_server_context   TYPE REF TO if_ws_server_context,
       lo_payload_protocol TYPE REF TO if_wsprotocol_payload.

lo_server_context   = cl_proxy_access=>get_server_context( ).
lo_payload_protocol ?=
     lo_server_context->get_protocol( if_wsprotocol=>payload ).

Features

The following table provides an overview of the available protocols and which runtime each one supports:

If you use GET_PROTOCOL to request a protocol that the runtime does not support, the method raises an exception.

Supported ABAP Proxy Runtime Protocols

Protocol Constant in IF_WS_PROTOCOL	Supported by		Use
	XI Runtime	Web Services Runtime
ASYNC_MESSAGING	Yes	No	Enables the quality of service Exactly-Once-in-Order in asynchronous communication and controls processing of acknowledgments.
ROUTING	Yes	No	Sets the receiver and other routing services.
ATTACHMENTS	Yes	Yes	Exchanges message attachments
XI_HEADER	Yes	No	Access to XI-specific message header fields.
PAYLOAD	Yes	Only XML handling, no query of payload	Extended XML handling (for example, for querying initial values and xsd:nil); querying the payload
MESSAGE_ID	Yes	Yes (if configured)	Accessing the message ID for the message sent
SESSION	No	Yes (for services with interface pattern stateful)	Creating or terminating a session on the receiver side with synchronous communication The logon context can be maintained over multiple calls. SAP recommends that you only use this protocol in exceptional cases.
WS_HEADER	No	Yes (only on the consumer side)	Access to Web service-specific message header fields (WS Header)

 

Accessing Protocol Classes Regardless of the Proxy Instance (XI Runtime)

The CL_PROXY_ACCRESS class has additional help methods that enable you to access ABAP proxy runtime objects without using a proxy instance:

Method	Use
GET_ACKNOWLEDGMENT	Reads the acknowledgment status of a message by using the message ID (refer to Acknowledgments).
GET_PRE_ROUTING	Returns an object of type IF_WS_PRE_ROUTING for receiver pre-identification for a proxy class.
GET_PAYLOAD_HANDLER	Returns a payload handler that you can use for rendering and parsing the XML payload.
GET_SERVER_CONTEXT	See above.

Furthermore, using additional methods of the class you can store relationships between PI messages and BOR application objects. For more information, refer to the class documentation for CL_PROXY_ACCESS  (Using Object Links).