Logging in most Google Cloud libraries is possible by enabling the logging of the lower-level libraries used to make the API calls. These libraries are GRPC and Google API Client.

require "logger"

app_logger = Logger.new $stderr
app_logger.level = Logger::WARN

# Set GRPC logger
GRPC::DefaultLogger::LOGGER = app_logger

# Set the Google API Client logger
Google::Apis.logger = app_logger

Logging can be very useful for debugging applications, or performance tuning. We think this should be documented somewhere that users can more easily discover which to choose for the library they are using.

See #1216 for more discussion about this.