Logging¶

TypedBus produces structured log output from all components when a logger is configured.

Enabling Logging¶

TypedBus.configure do |config|
  config.logger    = Logger.new($stdout)
  config.log_level = Logger::INFO
end

Or use the shortcut:

TypedBus.logger = Logger.new($stdout)

Set to nil (the default) to disable logging.

Log Level¶

Setting log_level automatically applies it to the logger:

TypedBus.configure do |config|
  config.logger    = Logger.new($stdout)
  config.log_level = Logger::DEBUG     # applies to the logger
end

# Or change it later:
TypedBus.configuration.log_level = Logger::WARN

What Gets Logged¶

INFO Level¶

Bus initialization
Channel creation with parameters
Subscriber registration and unsubscription
Message publish events
Delivery acks
DLQ drains
Channel close and clear operations

WARN Level¶

Delivery nacks
Delivery timeouts
DLQ entries added
Publishing with no subscribers

ERROR Level¶

Subscriber exceptions
Type mismatches

DEBUG Level¶

Individual subscriber notifications
Throttle delay calculations
Backpressure wait/resume events

Log Format¶

All log messages are prefixed with the originating component:

TypedBus::MessageBus message bus initialized (default_throttle=off)
TypedBus::Channel[:orders] channel created (type=Order, timeout=10s, max_pending=100, throttle=off)
TypedBus::Channel[:orders] published message (type=Order, subscribers=2)
TypedBus::Delivery[:orders#1] acked
TypedBus::DeliveryTracker[:orders] fully delivered (all 2 subscribers acked)

Custom Formatter¶

Use a custom formatter for colorized or structured output:

logger = Logger.new($stdout)
logger.formatter = proc do |severity, datetime, _progname, msg|
  timestamp = datetime.strftime("%H:%M:%S.%L")
  "#{timestamp} [#{severity.ljust(5)}] #{msg}\n"
end

TypedBus.configure do |config|
  config.logger    = logger
  config.log_level = Logger::DEBUG
end