EMA C++ RDM Usage Guide : 6 Market Price Domain : 6.2 Usage
 
6.2 Usage
6.2.1 Market Price Request Message
A Market Price request message is encoded using ReqMsg and sent by Open Message Model consumer applications. The request specifies the name and attributes of an item in which the consumer is interested.
To receive updates, a consumer can make a “streaming” request by setting ReqMsg.InterestAfterRefresh to true. If the method is not set, the consumer requests a “snapshot,” and the refresh ends the request (though updates might be received in either case if the refresh has multiple parts).
To stop updates, a consumer can pause an item (if the provider supports the pause feature). For additional details, refer to the Enterprise Message API C++ Edition Developers Guide.
 
Table 49: Market Price Request Message  
Component
Description / Value
DomainType
Required. MMT_MARKET_PRICE = 6
Interactions
Required.
InitialImage: true, indicates that an initial image is required.
InterestAfterRefresh: true, indicates that a streaming request is required.
Pause: true, indicates that a pause is required.
Indications
Optional.
ConflatedInUpdates: true, indicates conflated updates is required
Batch and View request are specified in the Payload.
QoS
Optional. Indicates the QoS at which the consumer wants the stream serviced. If both QoS and worstQos are specified, this request can be satisfied by a range of QoS.
worstQos
Optional. Used with the QoS member to define a range of acceptable QoS. When the provider encounters such a range, it should attempt to provide the best QoS it can within that range.
worstQos should only be used on services that claim to support it via the SupportsQosRange item in the Source Directory response (refer to Section 4.3.1.1).
NOTE: Enterprise Message API provides the Request.Qos() method to set both Qos and WorstQos depending upon the timeliness and rate values.
Priority
Optional. Indicates the class and count associated with stream priority.
extendedHeader
Not used.
ServiceId
Required. Specifies the ID of the service from which the consumer wishes to request the item.
NOTE: The application should set either the ServiceName or ServiceId of the service, but not both.
NameType
Optional. When consuming from LSEG sources, typically set to INSTRUMENT_NAME_RIC = 1 (the “Instrument Code”). If unspecified, NameType defaults to INSTRUMENT_NAME_RIC = 1.
Name
Required. Specifies the name of the requested item.
NOTE: Not used for Batch Item request.
ServiceName
Required. Specifies the name of the service from which the consumer wishes to request the item.
NOTE: The application should set either the ServiceName or ServiceId of the service, but not both.
Filter
Not used.
Identifier
Not used.
Attrib
Not used.
Payload
Optional. When features such as View or Batch are leveraged, the payload can contain information relevant to that feature. For more detailed information, refer to the Appendix A.