EMA C++ RDM Usage Guide : 5 Dictionary Domain : 5.3 Usage
 
5.3 Usage
5.3.1 Dictionary Request Message
A dictionary request message is encoded using ReqMsg and sent internally by the OmmConsumer in the constructor of this class. The request indicates the name of the desired dictionary and how much information from that dictionary is needed.
Users can configure dictionary request messages using OmmConsumerConfig.addAdminMsg() to override the default dictionary request.
Though updates are not sent on dictionary streams, LSEG recommends that the consumer make a streaming request (setting ReqMsg.InterestAfterRefresh to true) so that it is notified whenever the dictionary version changes.
 
Table 33: Dictionary Request Message  
COMPONENT
DESCRIPTION / VALUE
DomainType
Required. MMT_DICTIONARY = 5
Interactions
Required.
InitialImage: true, Indicates an initial image is required.
InterestAfterRefresh: true, Indicates a streaming request is required.
After receiving RefreshComplete, the consumer can only receive a Status response message. An Update response message will never be received. Pause request is not supported.
QoS
Not used.
worstQos
Not used.
priorityClass
Not used.
priorityCount
Not used.
Priority
Optional.
extendedHeader
Not used.
ServiceName
Required. Specifies the ServiceName of the service from which the consumer requests the dictionary.
NOTE: The application should set either the ServiceName or ServiceId of the service, but not both.
ServiceId
Required. Specifies the ServiceId of the service from which the consumer requests the dictionary.
NOTE: The application should set either the ServiceName or ServiceId of the service, but not both.
NameType
Not used.
Name
Required. Specifies the Name of the desired dictionary as seen in the Source Directory response (refer to Section 4.3.1.1).
Filter
Required. The filter represents the desired verbosity of the dictionary. The consumer should set the Filter according to how much information is needed:
DICTIONARY_INFO = 0x00: Provides version information only.
DICTIONARY_MINIMAL = 0x03: Provides information needed for caching.
DICTIONARY_NORMAL = 0x07: Provides all information needed for decoding.
DICTIONARY_VERBOSE = 0x0F: Provides all information (including comments).
Providers are not required to support the MINIMAL and VERBOSE filters.
For further details on Filter, refer to Section 5.4.1.
Identifier
Not used.
Attrib
Not used.
Payload
Not used.