burrow_format_logger.go

// Copyright Monax Industries Limited
// SPDX-License-Identifier: Apache-2.0

package loggers

import (
	"encoding"
	"encoding/json"
	"fmt"
	"sync"
	"time"

	"github.com/go-kit/kit/log"
	"github.com/hyperledger/burrow/logging/structure"
	"github.com/tmthrgd/go-hex"
)

// Logger that implements some formatting conventions for burrow and burrow-client
// This is intended for applying consistent value formatting before the final 'output' logger;
// we should avoid prematurely formatting values here if it is useful to let the output logger
// decide how it wants to display values. Ideal candidates for 'early' formatting here are types that
// we control and generic output loggers are unlikely to know about.
type burrowFormatLogger struct {
	sync.Mutex
	logger log.Logger
}

var _ log.Logger = &burrowFormatLogger{}

func (bfl *burrowFormatLogger) Log(keyvals ...interface{}) error {
	if bfl.logger == nil {
		return nil
	}
	keyvals, err := structure.MapKeyValues(keyvals,
		func(key interface{}, value interface{}) (interface{}, interface{}) {
			switch v := value.(type) {
			case string, json.Marshaler, encoding.TextMarshaler:
			case time.Time:
				value = v.Format(time.RFC3339Nano)
			case fmt.Stringer:
				value = v.String()
			case []byte:
				value = hex.EncodeUpperToString(v)
			}
			return structure.StringifyKey(key), value
		})
	if err != nil {
		return err
	}
	bfl.Lock()
	defer bfl.Unlock()
	return bfl.logger.Log(keyvals...)
}

func BurrowFormatLogger(logger log.Logger) *burrowFormatLogger {
	return &burrowFormatLogger{logger: logger}
}