JSON log output (#1027)

* WIP JSON log output

* Dont need isatty directly

* Dont output banner/startup info as reg text if not running with console output

* Dont run tests with -v as zap will log tests that fail

* Simplify

* Add test

* Update cmd/flipt/main.go

Co-authored-by: George <me@georgemac.com>

* Update cmd/flipt/main.go

Co-authored-by: George <me@georgemac.com>

* starting -> available

Co-authored-by: George <me@georgemac.com>

Taskfile.yml

@@ -150,5 +150,4 @@ tasks:
     vars:
       COVERAGE_FILE: coverage.txt
       TEST_PATTERN: .
-      TEST_FLAGS: -v
       TEST_OPTS: -race

cmd/flipt/main.go

@@ -80,7 +80,6 @@ var (
 
 	cfgPath      string
 	forceMigrate bool
-
 	version      = devVersion
 	commit       string
 	date         string
@@ -94,7 +93,7 @@ func main() {
 		once         sync.Once
 		loggerConfig = zap.Config{
 			Level:       zap.NewAtomicLevelAt(zap.InfoLevel),
-			Development: true,
+			Development: false,
 			Encoding:    "console",
 			EncoderConfig: zapcore.EncoderConfig{
 				// Keys can be anything except the empty string.
@@ -213,6 +212,13 @@ func main() {
 		if err != nil {
 			logger().Fatal("parsing log level", zap.String("level", cfg.Log.Level), zap.Error(err))
 		}
+
+		if cfg.Log.Encoding > config.LogEncodingConsole {
+			loggerConfig.Encoding = cfg.Log.Encoding.String()
+
+			// don't encode with colors if not using console log output
+			loggerConfig.EncoderConfig.EncodeLevel = zapcore.CapitalLevelEncoder
+		}
 	})
 
 	rootCmd.SetVersionTemplate(banner)
@@ -234,27 +240,30 @@ func main() {
 }
 
 func run(ctx context.Context, logger *zap.Logger) error {
-	color.Cyan(banner)
-	fmt.Println()
-
 	ctx, cancel := context.WithCancel(ctx)
-
 	defer cancel()
 
 	interrupt := make(chan os.Signal, 1)
 	signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
-
 	defer signal.Stop(interrupt)
 
 	shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer shutdownCancel()
 
 	var (
-		isRelease       = isRelease()
+		isRelease = isRelease()
+		isConsole = cfg.Log.Encoding == config.LogEncodingConsole
+
 		updateAvailable bool
 		cv, lv          semver.Version
 	)
 
+	if isConsole {
+		color.Cyan("%s\n", banner)
+	} else {
+		logger.Info("flipt starting", zap.String("version", version), zap.String("commit", commit), zap.String("date", date), zap.String("go_version", goVersion))
+	}
+
 	if isRelease {
 		var err error
 		cv, err = semver.ParseTolerant(version)
@@ -639,13 +648,26 @@ func run(ctx context.Context, logger *zap.Logger) error {
 
 		logger.Debug("starting http server")
 
-		color.Green("\nAPI: %s://%s:%d/api/v1", cfg.Server.Protocol, cfg.Server.Host, httpPort)
+		var (
+			apiAddr = fmt.Sprintf("%s://%s:%d/api/v1", cfg.Server.Protocol, cfg.Server.Host, httpPort)
+			uiAddr  = fmt.Sprintf("%s://%s:%d", cfg.Server.Protocol, cfg.Server.Host, httpPort)
+		)
 
-		if cfg.UI.Enabled {
-			color.Green("UI: %s://%s:%d", cfg.Server.Protocol, cfg.Server.Host, httpPort)
-		}
+		if isConsole {
+			color.Green("\nAPI: %s", apiAddr)
+
+			if cfg.UI.Enabled {
+				color.Green("UI: %s", uiAddr)
+			}
+
+			fmt.Println()
+		} else {
+			logger.Info("api available", zap.String("address", apiAddr))
 
-		fmt.Println()
+			if cfg.UI.Enabled {
+				logger.Info("ui available", zap.String("address", uiAddr))
+			}
+		}
 
 		if cfg.Server.Protocol == config.HTTPS {
 			httpServer.TLSConfig = &tls.Config{

config/config.go

@@ -32,10 +32,35 @@ type Config struct {
 }
 
 type LogConfig struct {
-	Level string `json:"level,omitempty"`
-	File  string `json:"file,omitempty"`
+	Level    string      `json:"level,omitempty"`
+	File     string      `json:"file,omitempty"`
+	Encoding LogEncoding `json:"encoding,omitempty"`
 }
 
+type LogEncoding uint8
+
+func (e LogEncoding) String() string {
+	return logEncodingToString[e]
+}
+
+const (
+	_ LogEncoding = iota
+	LogEncodingConsole
+	LogEncodingJSON
+)
+
+var (
+	logEncodingToString = map[LogEncoding]string{
+		LogEncodingConsole: "console",
+		LogEncodingJSON:    "json",
+	}
+
+	stringToLogEncoding = map[string]LogEncoding{
+		"console": LogEncodingConsole,
+		"json":    LogEncodingJSON,
+	}
+)
+
 type UIConfig struct {
 	Enabled bool `json:"enabled"`
 }
@@ -189,7 +214,8 @@ var (
 func Default() *Config {
 	return &Config{
 		Log: LogConfig{
-			Level: "INFO",
+			Level:    "INFO",
+			Encoding: LogEncodingConsole,
 		},
 
 		UI: UIConfig{
@@ -248,8 +274,9 @@ func Default() *Config {
 
 const (
 	// Logging
-	logLevel = "log.level"
-	logFile  = "log.file"
+	logLevel    = "log.level"
+	logFile     = "log.file"
+	logEncoding = "log.encoding"
 
 	// UI
 	uiEnabled = "ui.enabled"
@@ -325,6 +352,10 @@ func Load(path string) (*Config, error) {
 		cfg.Log.File = viper.GetString(logFile)
 	}
 
+	if viper.IsSet(logEncoding) {
+		cfg.Log.Encoding = stringToLogEncoding[viper.GetString(logEncoding)]
+	}
+
 	// UI
 	if viper.IsSet(uiEnabled) {
 		cfg.UI.Enabled = viper.GetBool(uiEnabled)

config/config_test.go

@@ -106,6 +106,36 @@ func TestDatabaseProtocol(t *testing.T) {
 	}
 }
 
+func TestLogEncoding(t *testing.T) {
+	tests := []struct {
+		name     string
+		encoding LogEncoding
+		want     string
+	}{
+		{
+			name:     "console",
+			encoding: LogEncodingConsole,
+			want:     "console",
+		},
+		{
+			name:     "json",
+			encoding: LogEncodingJSON,
+			want:     "json",
+		},
+	}
+
+	for _, tt := range tests {
+		var (
+			encoding = tt.encoding
+			want     = tt.want
+		)
+
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, want, encoding.String())
+		})
+	}
+}
+
 func TestLoad(t *testing.T) {
 	tests := []struct {
 		name     string
@@ -197,8 +227,9 @@ func TestLoad(t *testing.T) {
 			expected: func() *Config {
 				cfg := Default()
 				cfg.Log = LogConfig{
-					Level: "WARN",
-					File:  "testLogFile.txt",
+					Level:    "WARN",
+					File:     "testLogFile.txt",
+					Encoding: LogEncodingJSON,
 				}
 				cfg.UI = UIConfig{
 					Enabled: false,

config/testdata/advanced.yml

@@ -1,6 +1,7 @@
 log:
   level: WARN
   file: "testLogFile.txt"
+  encoding: "json"
 
 ui:
   enabled: false