EMA C++ RDM Usage Guide : 7 Market By Order Domain : 7.2 Usage
 
7.2 Usage
7.2.1 Market By Order Request Message
A Market By Order request message is encoded using ReqMsg and sent by Open Message Model consumer applications. The request specifies the name of the item in which a consumer is interested.
To receive updates, the consumer makes a “streaming” request by setting the ReqMsg.InterestAfterRefresh to true. If the method is not set, the consumer is requesting a “snapshot,” and the refresh should end the request. Updates may be received in either case if the refresh has multiple parts.
To stop updates, a consumer can pause an item if the provider supports this functionality. For additional details, refer to the Enterprise Message API C++ Edition Developers Guide.
 
Table 53: Market By Order Request Message  
COMPONENT
DESCRIPTION / VALUE
DomainType
Required. MMT_MARKET_BY_ORDER = 7
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.
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 qualities of service.
worstQos
Optional. Used with the QoS member to define a range of acceptable Qualities of Service. When encountering such a range, the provider should attempt to provide the best QoS it can within that range.
This 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. This should be the ID associated with the service from which the consumer wants to request the item.
NOTE: A consumer should set either the ServiceName or ServiceId of the service, but not both.
ServiceName
Required. This should be the name of the service from which the consumer wishes to request data.
NOTE: A consumer should set either the ServiceName or ServiceId of the service, but not both.
NameType
Optional. When consuming from LSEG sources, NameType is typically set to INSTRUMENT_NAME_RIC = 1 (the “Instrument Code”). If absent, the Enterprise Message API assumes a setting of INSTRUMENT_NAME_RIC = 1.
Name
Required. Specifies the requested item’s name.
 
NOTE: Not used for Batch Item requests.
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 Appendix A.