Kafka Message Dispatcher

API Documentation

The O-RAN SC Kafka Message Dispatcher is a specific implementation of an A1 Simulator ref:calloutserver, which further redirects A1 Policy operations to a Kafka message topic, to be consumed by an external function.

A1 Policy are redirected as Kafka messages to a configured Kafka Topic to an external receiver, then responses from the external receiver are collected from another configured Kafka Topic. This provides a Kafka-based request-response abstraction for adding supplemental simulator behavior for particular A1 Policy Types. After a request message is sent, a response message will be expected within some configurable timeout interval (default: 30 sec). The topics to be used for particular A1 Policy Types is configured using a JSON map (Example: policytype_to_topicmap.json <../near-rt-ric-simulator/test/KAFKA_DISPATCHER/resources/policytype_to_topicmap.json>

Note: As with other A1 Simulator call-out servers, the Kafka message dispatcher functionality is only available for ‘STD_2.0.0’ version simulators.

The Kafka message dispatcher exposes a ‘Kafka Message Dispatcher’ REST API. This internal API is invoked directly by the A1 Simulator, and is not intended to be used by any other client. This API is documented in Kafka Message Dispatcher API and in OpenAPI YAML format:

API name
Kafka Message Dispatcher API	link

The Kafka message dispatcher also exposes an ‘Admin API’ to manipulate the behavior of the Kafka message dispather itself. The ‘Kafka Message Dispatcher Admin API’ is documented below:

Admin Functions

Health Check

GET

Returns the status of the Kafka Message Dispatcher.

URL path:

/

Parameters:

None.

Responses:

200:

OK

Examples:

Call:

curl -X GET "http://localhost:7075/"

Result:

200:

OK

Response manipulation

It is possible to manipulate the response of all operations on the Kafka Message Dispatcher module

POST

Force a specific response code for the all (the next) Kafka Message Dispatcher module operations. Unless it is reset, it will always send the same response code back.

URL path:

/dispatcheradmin/forceresponse?code=<http-response-code>

Parameters:

code: (Required)

The HTTP response code to return.

Responses:

200:

Force response code: <expected code> set for all all dispatcher response until it is resetted

Examples:

Call:

curl -X POST "http://localhost:7075/dispatcheradmin/forceresponse?code=500"

Result:

200:

Force response code: 500 set for all dispatcher response until it is resetted

Reset response-manipulation

It is possible to reset the response manipulation on the Kafka Message Dispatcher module

POST

Clears specific response code for all (the next) Kafka Message Dispatcher module operation.

URL path:

/dispatcheradmin/forceresponse

Parameters:

code: (Required)

The HTTP response code to return.

Responses:

200:

Force response code has been resetted for dispatcher responses

Examples:

Call:

curl -X POST "http://localhost:7075/dispatcheradmin/forceresponse"

Result:

200:

Force response code has been resetted for dispatcher responses

Response time manipulation

It is possible to set a period of time to delay response time.

POST

Force delayed response of all dispatcher responses. The setting will remain until the delay is cleared.

URL path:

/dispatcheradmin/forcedelay?delay=<delay-time-seconds>

Parameters:

delay: (Required)

The time in seconds to delay all responses.

Responses:

200:

Force delay: <expected_delay> sec set for all dispatcher responses until it is resetted

Examples:

Call:

curl -X POST "http://localhost:7075/dispatcheradmin/forcedelay?delay=5"

Result:

200:

Force delay: 5 sec set for all dispatcher responses until it is resetted

Reset response time manipulation

It is also possible to reset delay response time.

POST

The setting will clear the delay.

URL path:

/dispatcheradmin/forcedelay

Parameters:

None.

The time in seconds to delay all responses.

Responses:

200:

Force delay has been resetted for all dispatcher responses

Examples:

Call:

curl -X POST "http://localhost:7075/dispatcheradmin/forcedelay"

Result:

200:

Force delay has been resetted for all dispatcher responses