Injector

The injector is used to inject events directly into specific IP block emulators at provided timestamps/offsets.

Injector Configuration

If the injector is being run through kubernetes/minikube, the injector config is passed automatically as part of the Helm chart (see Helm Configuration). Otherwise, the injector will fall back to injector_config.json. This configuration specifies RabbitMQ connection info as well as a list of emulators. Example configuration:

{
  "rabbitmq_host": "rabbitmq",
  "rabbitmq_port": 5672,
  "bitstream_emulators": [
    "fhs-vcc-emulator-1",
    "fhs-vcc-emulator-2"
  ]
}

Using the Injector / API

Injecting events into an emulator is as simple as sending an API request. This may contain one or several events at a time, so long as the JSON follows the above specification.

If running via minikube/k8s (the preferred way), the hostname for the injector is

injector-service.ska-mid-cbf-emulators.svc.cluster.local:5002

which can be accessed via any pod in the cluster, e.g.

curl -v -d @events_body.json -H 'Content-Type: application/json' injector-service.ska-mid-cbf-emulators.svc.cluster.local:5002/inject

Otherwise, for Docker, it is http://injector:5002 (preferred by Docker) or http://localhost:5002 and is only accessible from within the same container as the running injector.

Inject events

POST /inject

Inject events into an emulator.

Example request:

curl -v -d @events_body.json -H 'Content-Type: application/json' injector-service.ska-mid-cbf-emulators.svc.cluster.local:5002/inject

events_body.json follows this schema, of which an example looks like:

{
  "injector_event_groups": [
    {
      "bitstream_emulator_id": "fhs-vcc-emulator-1",
      "ip_block_emulator_id": "ethernet_200g",
      "events": [
        {
          "severity": "WARNING",
          "value": {
            "id": "inj01234",
            "injection_type": "update_link_badness",
            "message": "Degrade the link.",
            "badness": 0.75
          },
          "offset": 10000
        },
        {
          "severity": "GENERAL",
          "value": {
            "id": "inj01235",
            "injection_type": "update_link_badness",
            "message": "Fix the link.",
            "badness": 0.2
          },
          "offset": 20000
        }
      ]
    },
    {
      "bitstream_emulator_id": "fhs-vcc-emulator-2",
      "ip_block_emulator_id": "wideband_input_buffer",
      "events": [
        {
          "severity": "FATAL_ERROR",
          "value": {
            "id": "inj01236",
            "injection_type": "fault",
            "message": "The Wideband Input Buffer has been hit by a meteorite."
          },
          "timestamp": 1727740800000
        }
      ]
    }
  ]
}

Example response:

{}

Request JSON Object:

injector_event_groups (list[object]) – a list of event groups, in which each event group specifies a list of events for a specific IP block in a specific bitstream emulator.
bitstream_emulator_id (string) – the bitstream emulator ID to inject this group of events into.
ip_block_emulator_id (string) – the IP block emulator ID within the specified bitstream emulator to inject this group of events into.
events (list[object]) – a list of event objects to inject.
severity (string) – the severity of this event. Must be a member of the EventSeverity enum.
offset (string) – an offset, in milliseconds from the start of injection, by which to delay this event’s injection. May not be used in conjunction with timestamp.
timestamp (string) – a specific timestamp, in milliseconds from the emulator’s epoch, at which to trigger this event’s injection. May not be used in conjunction with offset.
value (object) –

an arbitrary value object to inject.
Must contain an injection_type property, but is otherwise unrestricted.

reqjson string injection_type:

an arbitrary string representing the type of injection.

Request Headers:

Content-Type – application/json

Response Headers:

Content-Type – application/json

Status Codes:

200 OK – Injections successfully queued.
400 Bad Request – The provided body encountered validation errors.

Signal Generator Injection

[TODO] The Signal Generator also supports certain injected events in order to change signal values during runtime. The update_signal_properties injection type allows you to update specific signal values, and the update_signal injection type allows you to update the entire signal all at once. See the Signal Generator injection schema for more details.

For example:

{
  "injector_event_groups": [
    {
      "bitstream_emulator_id": "fhs-vcc-emulator-1",
      "ip_block_emulator_id": "signal_generator",
      "events": [
        {
          "severity": "GENERAL",
          "value": {
            "id": "inj1000",
            "injection_type": "update_signal_properties",
            "message": "Update the sample rate.",
            "updated_properties": {
              "sample_rate": 3_900_123_456
            }
          },
          "offset": 10000
        },
        {
          "severity": "GENERAL",
          "value": {
              "id": "inj1001",
              "injection_type": "update_signal",
              "message": "Change the initial signal.",
              "signal": {
                  "packet_rate": 1_500_123.5,
                  "sample_rate": 3_900_456_789,
                  "dish_id": "MKT004",
                  "band_id": "4",
                  "regular_sky_power": [0.7, 0.9],
                  "noise_diode_on_power": [0.8, 0.95],
                  "duty_cycle": 0.79
              }
          }
          "offset": 20000
        }
      ]
    }
  ]
}