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Plugins

Lightbus ships with two plugins, both of which are disabled by default.

State Plugin

Every Lightbus worker process which has the state plugin enabled will report it's state to the bus. This state information is available as the following events on the internal.state API.

This plugin should add minimal load to the bus and may be useful in developing tooling around the bus.

Events

worker_started

Parameters: process_name, metrics_enabled, api_names, listening_for, timestamp, ping_interval

Fired when the worker starts up.

worker_ping

Parameters: process_name, metrics_enabled, api_names, listening_for, timestamp, ping_interval

Fires every 60 seconds after worker startup. This indicates that the worker is still alive and has not died unexpectedly. This interval is configurable (see below).

worker_stopped

Parameters: process_name, timestamp

Fires when a worker shuts down cleanly.

Configuration

The following configuration options are available:

enabled (bool)

Default: False

Should the plugin be enabled?

ping_enabled (bool)

Default: True

Should ping messages be sent?

ping_enabled (int, seconds)

Default: 60

How often (in seconds) should a ping event be sent. A lower interval means more frequent messages, but reduces the time it takes any listeners to discover dead workers.

Example configuration

bus:
  ...

apis:
  ...

plugins:
  internal_state:
    enabled: true
    ping_enabled: true
    ping_interval: 60

Metrics Plugin

The metrics plugin sends metric events for every event & RPC processes. It therefore has a much bigger impact on performance than the state plugin, but also provides much more detailed information.

Events

The following events will be fired on the internal.metrics API:

Event	Parameters
rpc_call_sent	process_name, id, api_name, procedure_name, kwargs, timestamp
rpc_call_received	process_name, id, api_name, procedure_name, timestamp
rpc_response_sent	process_name, id, api_name, procedure_name, result, timestamp
rpc_response_received	process_name, id, api_name, procedure_name, timestamp
event_fired	process_name, event_id, api_name, event_name, kwargs, timestamp
event_received	process_name, event_id, api_name, event_name, kwargs, timestamp
event_processed	process_name, event_id, api_name, event_name, kwargs, timestamp

Configuration

The metrics plugin only includes the enabled configuration option. Configuration should therefore be:

bus:
  ...

apis:
  ...

plugins:
  internal_metrics:
    enabled: true