tendermint/log/logger.go

package log

import (
	"fmt"

	kitlog "github.com/go-kit/kit/log"
	"github.com/go-kit/kit/log/level"
)

// Logger is what any Tendermint library should take.
type Logger interface {
	Debug(msg string, keyvals ...interface{}) error
	Info(msg string, keyvals ...interface{}) error
	Error(msg string, keyvals ...interface{}) error
}

// With returns a new contextual logger with keyvals prepended to those passed
// to calls to Info, Debug or Error.
func With(logger Logger, keyvals ...interface{}) Logger {
	switch logger.(type) {
	case *tmLogger:
		return &tmLogger{kitlog.With(logger.(*tmLogger).srcLogger, keyvals...)}
	case *nopLogger:
		return logger
	default:
		panic(fmt.Sprintf("Unexpected logger of type %T", logger))
	}
}

// WithLevel returns a copy of the logger with a level set to lvl.
func WithLevel(logger Logger, lvl string) Logger {
	switch logger.(type) {
	case *tmLogger:
		switch lvl {
		case "info":
			return &tmLogger{level.NewFilter(logger.(*tmLogger).srcLogger, level.AllowInfo())}
		case "debug":
			return &tmLogger{level.NewFilter(logger.(*tmLogger).srcLogger, level.AllowDebug())}
		case "error":
			return &tmLogger{level.NewFilter(logger.(*tmLogger).srcLogger, level.AllowError())}
		default:
			panic(fmt.Sprintf("Unexpected level %v, expect either \"info\" or \"debug\" or \"error\"", lvl))
		}
	case *nopLogger:
		return logger
	default:
		panic(fmt.Sprintf("Unexpected logger of type %T", logger))
	}
}