+ static final String ENGINE_INSTANCE_ID = "engine_instance_id";
+ static final Gauge ENGINE_EVENT_EXECUTIONS = Gauge.build().name("engine_event_executions")
+ .namespace(PrometheusUtils.PdpType.PDPA.getNamespace()).labelNames(ENGINE_INSTANCE_ID)
+ .help("Total number of APEX events processed by the engine.").register();
+ static final Gauge ENGINE_UPTIME = Gauge.build().name("engine_uptime")
+ .namespace(PrometheusUtils.PdpType.PDPA.getNamespace()).labelNames(ENGINE_INSTANCE_ID)
+ .help("Time elapsed since the engine was started.").register();
+ static final Gauge ENGINE_START_TIMESTAMP = Gauge.build().name("engine_last_start_timestamp_epoch")
+ .namespace(PrometheusUtils.PdpType.PDPA.getNamespace()).labelNames(ENGINE_INSTANCE_ID)
+ .help("Epoch timestamp of the instance when engine was last started.").register();
+ static final Gauge ENGINE_AVG_EXECUTION_TIME = Gauge.build().name("engine_average_execution_time_seconds")
+ .namespace(PrometheusUtils.PdpType.PDPA.getNamespace()).labelNames(ENGINE_INSTANCE_ID)
+ .help("Average time taken to execute an APEX policy in seconds.").register();
+ static final Histogram ENGINE_LAST_EXECUTION_TIME = Histogram.build()
+ .namespace(PrometheusUtils.PdpType.PDPA.getNamespace())
+ .name("engine_last_execution_time").labelNames(ENGINE_INSTANCE_ID)
+ .help("Time taken to execute the last APEX policy in seconds.").register();