pkg/config/config.go

@@ -118,6 +118,34 @@ type SamplerConfig struct {
 	Ratio float64 `mapstructure:"ratio"`
 }
 
+// peekJSONLogging determines whether JSON logging should be used before the full
+// config is loaded, solving the chicken-and-egg problem where the logger format
+// must be known before any log is emitted, yet the format is stored in the config.
+//
+// Resolution order (mirrors Viper's own priority):
+//  1. DLC_LOGGING_JSON env var — checked directly via os.Getenv (zero overhead)
+//  2. logging.json key in the config file — read with a minimal throwaway Viper
+//     instance so we don't parse the whole config twice unnecessarily
+func peekJSONLogging() bool {
+	// 1. Env var takes highest priority — check it first
+	if env := os.Getenv("DLC_LOGGING_JSON"); env != "" {
+		return strings.EqualFold(env, "true") || env == "1"
+	}
+
+	// 2. Try to read logging.json from the config file
+	preV := viper.New()
+	preV.SetDefault("logging.json", false)
+	if configFile := os.Getenv("DLC_CONFIG_FILE"); configFile != "" {
+		preV.SetConfigFile(configFile)
+	} else {
+		preV.SetConfigName("config")
+		preV.SetConfigType("yaml")
+		preV.AddConfigPath(".")
+	}
+	_ = preV.ReadInConfig() // ignore errors — defaults apply on failure
+	return preV.GetBool("logging.json")
+}
+
 // LoadConfig loads configuration from file, environment variables, and defaults
 // Configuration priority: file > environment variables > defaults
 // To specify a custom config file path, set DLC_CONFIG_FILE environment variable
@@ -129,9 +157,17 @@ func LoadConfig() (*Config, error) {
 
 	v := viper.New()
 
-	// Set up initial console logging for config loading messages
+	// Configure the logger format before emitting any log output.
-	consoleWriter := zerolog.ConsoleWriter{Out: os.Stderr}
+	// peekJSONLogging reads the JSON setting early (env var + config file pre-read)
-	log.Logger = log.Output(consoleWriter)
+	// so that every log line — including those produced during config loading — is
+	// already in the correct format.
+	jsonLogging := peekJSONLogging()
+	if jsonLogging {
+		log.Logger = log.Output(os.Stderr)
+	} else {
+		log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})
+	}
+	log.Info().Bool("json", jsonLogging).Msg("Logging configured")
 
 	// Set default values
 	v.SetDefault("server.host", "0.0.0.0")
@@ -227,15 +263,9 @@ func LoadConfig() (*Config, error) {
 		return nil, fmt.Errorf("config unmarshal error: %w", err)
 	}
 
-	// Configure log output format (JSON or console) first
+	// Setup logging based on configuration (level, output file, time format).
-	if config.Logging.JSON {
+	// The JSON/console format was already applied at the top of LoadConfig via
-		log.Logger = log.Output(os.Stderr)
+	// peekJSONLogging, so SetupLogging only needs to handle the remaining knobs.
-	} else {
-		consoleWriter := zerolog.ConsoleWriter{Out: os.Stderr}
-		log.Logger = log.Output(consoleWriter)
-	}
-
-	// Setup logging based on configuration
 	config.SetupLogging()
 
 	log.Info().

scripts/start-server.sh

@@ -4,7 +4,8 @@
 # This script starts the server in the background and provides control functions
 
 # Configuration
-PROJECT_DIR="/Users/gabrielradureau/Work/Vibe/dance-lessons-coach"
+SCRIPTS_DIR=$(dirname "$(realpath "${BASH_SOURCE[0]}")")
+PROJECT_DIR=$(dirname "$SCRIPTS_DIR")
 SERVER_CMD="go run ./cmd/server"
 LOG_FILE="server.log"
 PID_FILE="server.pid"

scripts/test-graceful-shutdown.sh

@@ -7,7 +7,8 @@
 set -e
 
 # Configuration
-PROJECT_DIR="/Users/gabrielradureau/Work/Vibe/dance-lessons-coach"
+SCRIPTS_DIR=$(dirname "$(realpath "${BASH_SOURCE[0]}")")
+PROJECT_DIR=$(dirname "$SCRIPTS_DIR")
 SERVER_CMD="./scripts/start-server.sh"
 LOG_FILE="server.log"
 PID_FILE="server.pid"

scripts/test-opentelemetry.sh

@@ -9,7 +9,8 @@ echo -e "\033[1;34m=== dance-lessons-coach OpenTelemetry Test ===\033[0m"
 echo ""
 
 # Configuration
-PROJECT_DIR="/Users/gabrielradureau/Work/Vibe/dance-lessons-coach"
+SCRIPTS_DIR=$(dirname "$(realpath "${BASH_SOURCE[0]}")")
+PROJECT_DIR=$(dirname "$SCRIPTS_DIR")
 SERVER_CMD="./scripts/start-server.sh"
 LOG_FILE="server.log"
 PID_FILE="server.pid"