Querying the XI Message Header

Use

Using this protocol you can query the fields of the message header after a proxy call.

Integration

You can also query the fields of the message header during a mapping or by using technical context objects in the Integration Directory. See also: Container Object (message mappings), Java Mapping , XSLT Mapping .

Features

Using the Protocol Depending on the Call Situation

Proxy Call Readable Message Header

Asynchronous proxy call at sender

Message header of request message

Synchronous proxy call at sender

Message header of response message

Synchronous/asynchronous proxy call at receiver

Message header of request message

Fields in Message Header

The GET_HEADER_FIELD method returns the value of a field in the message header as a string. There is a constant in the IF_WSPROTOCOL_XI_HEADER interface for each readable field of the message header.

Accessing Message Header Fields by Using Constants

Constant Meaning

MESSAGE_CLASS

Classification of message. Possible values:

  • ApplicationMessage: Asynchronous or synchronous request message
  • ApplicationResponse: Response to request message
  • SystemAck, ApplicationAck, SystemError, ApplicationError: Acknowledgments

VERSION_MAJOR

XI message protocol version. Example: For the XI 3.0 message protocol VERSION_MAJOR = 3 and VERSION_MINOR = 0.

VERSION_MINOR

PROCESSING_MODE

The mode of a message can be synchronous or asynchronous. Correspondingly, these constants can have the value synchronous or asynchronous.

MESSAGE_ID

The message ID. It can change during communication:

Response messages get a new message ID.

If new messages result from a message (the message is copied at multiple receivers), the new messages get new message IDs.

REF_TO_MESSAGE_ID

The ID of a referenced message that belongs semantically to this message.For example, a response message uses this field to note which request message it belongs to.

CONVERSATION_ID

This field is not mandatory in the message. It enables an ID to be used to group messages that belong together. This field is not intended to be used for message serialization and has nothing to do with the serialization context (see context object QueueId).

TIME_SENT

Time stamp specifying when the message was sent by the sender. The format of the time stamp is as follows:

YYYY-MM-DDTHH:MM:SSZ

The letter 'T' separates the date from the time, which is generally specified in UTC. If it is a local time, the closing 'Z' is omitted.

INTERFACE

Name of the sender interface.

INTERFACE_NAMESPACE

Namespace of the sender interface.

SENDER_PARTY

Communication party that sent the message.

SENDER_PARTY_AGENCY

Issuing agency for the message sender.

SENDER_PARTY_SCHEME

Identification scheme used by the sender.

SENDER_SERVICE

Service on the sender side that sent the message.For example, the name of a business system.

RECEIVER_PARTY

Communication party to receive the message.

RECEIVER_PARTY_AGENCY

Issuing agency for the message receiver.

RECEIVER_PARTY_SCHEME

Identification scheme used by the receiver.

RECEIVER_SERVICE

Service on the receiver side that receives the message. For example, the name of a business system.

QUALITY_OF_SERVICE

Specifies the quality of service used to process the message. Possible values are BestEffort, ExactlyOnce, or ExactlyOnceInOrder.

QUEUE_ID

Only relevant for QUALITY_OF_SERVICE = "ExactlyOnceInOrder".

The value in this field corresponds to the serialization context that a sender uses to bundle related asynchronous messages (see also: ABAP runtime, Java proxy runtime).

The following message header fields are only relevant for MessageClass="ApplicationMessage" and ProcessingMode="asynchronous"(see above). They can have the Boolean value true or false. See also: Acknowledgments .

Fields of the Message Header for Acknowledgments

Constant Meaning

SYSTEM_ACK_REQUESTED

If the value of this field is true, the sender requested a positive system acknowledgment.

SYSTEM_ERROR_ACK_REQUESTED

If the value of this field is true, the sender requested a negative system acknowledgment.

APPLICATION_ACK_REQUESTED

If the value of this field is true, the sender requested a positive application acknowledgment.

APPLICATION_ERROR_ACK_REQUESTD

If the value of this field is true, the sender requested a negative application acknowledgment.

Example

In the following example, the IF_WSPROTOCOL_XI_HEADER protocol is used to access the MESSAGE_CLASS field in the message header of the response message at the receiver.

DATA: interface           TYPE REF TO co_sxidag_fsa_query,      request             TYPE sxidag_fsa_query_mt,      response            TYPE sxidag_fsa_response_mt,      xi_header_protocol  TYPE REF TO if_wsprotocol_xi_header,      xi_header_value     TYPE string.

* create instanceCREATE OBJECT  interface

* fill request datarequest-flight_seat_availability_query-flight_id-airline_id = 'LH'.

TRY.

*   get xi_header protocol    xi_header_protocol ?=  interface->get_protocol(                  if_wsprotocol=>xi_header ).

*   call client proxy    CALL METHOD interface->execute_synchronous      EXPORTING        output = request      IMPORTING        input  = response.

*   get header field    xi_header_value = xi_header_protocol->get_header_field( if_wsprotocol_xi_header=>message_class ).

CATCH cx_ai_system_fault .  CATCH cx_ai_application_fault .

ENDTRY.