SOW Statistics Events

AMPS can publish SOW statistics for each SOW topic which has been configured. To enable this functionality, specify the SOWStatsInterval in the configuration file. The value provided in SOWStatsInterval is the time between updates to the /AMPS/SOWStats topic.

For example, the following would be a configuration that would publish /AMPS/SOWStats event messages every 5 seconds.

<AMPSConfig>
    ...
    <SOWStatsInterval>5s</SOWStatsInterval>
    ...
</AMPSConfig>

When a SOWStatsInterval is provided, AMPS publishes a message for each topic defined in the SOW at the requested interval. These messages contain basic information about the topic. The format of the /AMPS/SOWStats messages matches the message type of the connection that has requested the messages.

For example, the following message provides information in JSON format about a topic named a-sample-topic. That topic is of message type bflat.

{
 "SOWStats":{
    "message_type":"bflat",
    "topic":"a-sample-topic",
    "record_count":15021,
    "timestamp":"20161108T225452.280650Z"
 }
}

In the SOWStats message above, message_type provides the name of the message type, topic specifies the name of the topic, record_count shows the number of records currently in the topic and timestamp includes the time the event was generated.

The table below defines the header fields which may be returned as part of the subscription messages to the /AMPS/SOWStats topic.

FIX	XML	JSON/BSON/MsgPack	Definition
20007	MessageType	message_type	The message type of the topic.
20065	Timestamp	timestamp	Timestamp in which AMPS sent the message.
20066	Topic	topic	Topic that statistics are being reported on.
20067	Records	record_count	Number of records in the SOW topic.

For compatibility with systems that expect a consistent set of FIX tags across messages, AMPS provides a set of FIX tags that are unified with the tags used in the /AMPS/ClientStatus topic. To use the unified FIX tags, set the AMPSVersionCompliance configuration element to 5. The following table lists the unified FIX tags:

FIX	Definition
20007	The message type of the topic.
20065	Timestamp in which AMPS sent the message.
20068	Topic that statistics are being reported on.
20075	Number of records in the SOW topic.

The /AMPS/SOWStats topic is not available for protobuf, composite, binary or struct message types.

AMPS will report statistics for topics of those types, but the format for the messages that AMPS generates must be a message type that can accept arbitrary fields, not a message type that requires a single schema.