FromContext returns zap.Logger from context.

New creates a new zap logger with the given log level, service name and environment.

NewDiscard creates logger which output to ioutil.Discard.

SetDefaultLogger sets the specified zap.Logger as default logger.

WithContext creates a new context with a new zap.Logger specified by argument.

WithFields adds zap.Fields to the zap.Logger in the context directly and create a new context with it.