Discovery is the process of enumerating resources to be used throughout the rest of the system. A discovery plugin interacts with any external system (for e.g. a CMDB) and produces a set of resources, with relevant metadata, which can be used by the rest of the system.
The base Panoptes package contains a discovery plugin that can read a JSON file for a list of resources and add them to the system.
The enrichment subsystem in Panoptes schedules and executes enrichment plugins and upserts their output into Redis.
Polling is the act of actually collecting metrics. As mentioned above, polling plugins (like all other plugins) are Python code and thus can collect from any source - SNMP, API, CLI.
The polling agent has the ability to apply transforms to telemetry collected by polling plugins - this is done before the data is placed on the message bus. Currently, there is only one implemented transformation - conversion from counter to gauge. This is immensely useful for network telemetry since a lot of devices return only counters.
The polling agent places collected and transformed metrics onto topics on the Kafka bus.
Consumers take the data produced by the discovery, enrichment or polling subsystems and integrate them with external systems. The base Panoptes package ships with a consumer to transform metrics and emit metrics to InfluxDB.