implement structured logging

utils/config.go

@@ -35,6 +35,8 @@ type ConfigStructure struct { // nolint: maligned
 	AzurePublishRoots      map[string]AzurePublishRoot      `json:"AzurePublishEndpoints"`
 	AsyncAPI               bool                             `json:"AsyncAPI"`
 	EnableMetricsEndpoint  bool                             `json:"enableMetricsEndpoint"`
+	LogLevel               string                           `json:"logLevel"`
+	LogFormat              string                           `json:"logFormat"`
 }
 
 // FileSystemPublishRoot describes single filesystem publishing entry point
@@ -112,6 +114,8 @@ var Config = ConfigStructure{
 	AzurePublishRoots:      map[string]AzurePublishRoot{},
 	AsyncAPI:               false,
 	EnableMetricsEndpoint:  false,
+	LogLevel:               "debug",
+	LogFormat:              "default",
 }
 
 // LoadConfig loads configuration from json file

utils/config_test.go

@@ -47,6 +47,9 @@ func (s *ConfigSuite) TestSaveConfig(c *C) {
 	s.config.AzurePublishRoots = map[string]AzurePublishRoot{"test": {
 		Container: "repo"}}
 
+	s.config.LogLevel = "info"
+	s.config.LogFormat = "json"
+
 	err := SaveConfig(configname, &s.config)
 	c.Assert(err, IsNil)
 
@@ -131,7 +134,9 @@ func (s *ConfigSuite) TestSaveConfig(c *C) {
 		"    }\n"+
 		"  },\n"+
 		"  \"AsyncAPI\": false,\n"+
-		"  \"enableMetricsEndpoint\": false\n"+
+		"  \"enableMetricsEndpoint\": false,\n"+
+		"  \"logLevel\": \"info\",\n"+
+		"  \"logFormat\": \"json\"\n"+
 		"}")
 }
 

utils/logging.go

@@ -0,0 +1,68 @@
+package utils
+
+import (
+	"io"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+type LogWriter struct {
+	Logger zerolog.Logger
+}
+
+func (lw LogWriter) Write(bs []byte) (int, error) {
+	return lw.Logger.With().Str("level", "info").Logger().Write(bs)
+}
+
+func SetupJSONLogger(levelStr string, w io.Writer) {
+	// zerolog.SetGlobalLevel(GetLogLevelOrDebug(levelStr))
+
+	zerolog.MessageFieldName = "message"
+	zerolog.LevelFieldName = "level"
+	// zerolog.TimestampFieldName= "time"
+
+	var tsHook timestampHook
+	log.Logger = zerolog.New(w).
+		Hook(&tsHook).
+		Level(GetLogLevelOrDebug(levelStr))
+}
+
+func SetupDefaultLogger(levelStr string) {
+	zerolog.MessageFieldName = "message"
+	zerolog.LevelFieldName = "level"
+
+	log.Logger = zerolog.New(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: time.RFC3339}).
+		Level(GetLogLevelOrDebug(levelStr)).
+		With().
+		Timestamp().
+		Logger()
+}
+
+func GetLogLevelOrDebug(levelStr string) zerolog.Level {
+	levelStr = strings.ToLower(levelStr)
+	if levelStr == "warning" {
+		levelStr = "warn"
+	}
+
+	var level zerolog.Level
+
+	err := level.UnmarshalText([]byte(levelStr))
+	if err == nil {
+		return level
+	}
+
+	log.Warn().Msgf("Unknown log level '%s', defaulting to debug", levelStr)
+	return zerolog.DebugLevel
+}
+
+type timestampHook struct{}
+
+func (h *timestampHook) Run(e *zerolog.Event, l zerolog.Level, msg string) {
+	t := time.Now()
+	ts := t.Format(time.RFC3339)
+	e.Str("time", ts)
+}