feat: load explicit configuration references and remove implicit env overlays

database/database.go

@@ -5,17 +5,16 @@ package database
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
 	"errors"
 	"fmt"
-	"os"
-	"strconv"
 	"strings"
 	"time"
 )
 
 type Config struct {
 	Driver          string        `json:"driver"`
-	DSN             string        `json:"-"`
+	DSN             string        `json:"dsn"`
 	MaxOpenConns    int           `json:"maxOpenConns"`
 	MaxIdleConns    int           `json:"maxIdleConns"`
 	ConnMaxLifetime time.Duration `json:"connMaxLifetime"`
@@ -23,6 +22,14 @@ type Config struct {
 	PingTimeout     time.Duration `json:"pingTimeout"`
 }
 
+// MarshalJSON omits the connection credential from serialized diagnostics.
+func (c Config) MarshalJSON() ([]byte, error) {
+	type plain Config
+	safe := plain(c)
+	safe.DSN = ""
+	return json.Marshal(safe)
+}
+
 func DefaultConfig() Config { return DefaultPoolConfig().config() }
 
 // PoolConfig returns driver-independent connection pool settings.
@@ -34,49 +41,6 @@ func (c Config) PoolConfig() PoolConfig {
 	}
 }
 
-// ConfigFromEnv reads GO_OMNI_DB_* style settings. DSN is required.
-func ConfigFromEnv(prefix string) (Config, error) {
-	return ApplyEnv(DefaultConfig(), prefix)
-}
-
-// ApplyEnv overlays nonempty environment settings on file/default configuration.
-// DSN is environment-only when Config is decoded from JSON or YAML.
-func ApplyEnv(cfg Config, prefix string) (Config, error) {
-	prefix = strings.TrimSpace(prefix)
-	if prefix == "" {
-		prefix = "GO_OMNI_DB_"
-	}
-	if value := strings.TrimSpace(os.Getenv(prefix + "DRIVER")); value != "" {
-		cfg.Driver = value
-	}
-	if cfg.Driver == "" {
-		cfg.Driver = "mysql"
-	}
-	if value := strings.TrimSpace(os.Getenv(prefix + "DSN")); value != "" {
-		cfg.DSN = value
-	}
-	if cfg.DSN == "" {
-		return Config{}, fmt.Errorf("%sDSN is required", prefix)
-	}
-	var err error
-	if cfg.MaxOpenConns, err = envInt(prefix+"MAX_OPEN_CONNS", cfg.MaxOpenConns); err != nil {
-		return Config{}, err
-	}
-	if cfg.MaxIdleConns, err = envInt(prefix+"MAX_IDLE_CONNS", cfg.MaxIdleConns); err != nil {
-		return Config{}, err
-	}
-	if cfg.ConnMaxLifetime, err = envDuration(prefix+"CONN_MAX_LIFETIME", cfg.ConnMaxLifetime); err != nil {
-		return Config{}, err
-	}
-	if cfg.ConnMaxIdleTime, err = envDuration(prefix+"CONN_MAX_IDLE_TIME", cfg.ConnMaxIdleTime); err != nil {
-		return Config{}, err
-	}
-	if cfg.PingTimeout, err = envDuration(prefix+"PING_TIMEOUT", cfg.PingTimeout); err != nil {
-		return Config{}, err
-	}
-	return cfg, cfg.Validate()
-}
-
 func (c Config) Validate() error {
 	if strings.TrimSpace(c.Driver) == "" {
 		return errors.New("database driver is required")
@@ -165,27 +129,3 @@ func (db *DB) InTx(ctx context.Context, options *sql.TxOptions, work func(*sql.T
 	}
 	return nil
 }
-
-func envInt(key string, fallback int) (int, error) {
-	value := strings.TrimSpace(os.Getenv(key))
-	if value == "" {
-		return fallback, nil
-	}
-	parsed, err := strconv.Atoi(value)
-	if err != nil {
-		return 0, fmt.Errorf("%s must be an integer: %w", key, err)
-	}
-	return parsed, nil
-}
-
-func envDuration(key string, fallback time.Duration) (time.Duration, error) {
-	value := strings.TrimSpace(os.Getenv(key))
-	if value == "" {
-		return fallback, nil
-	}
-	parsed, err := time.ParseDuration(value)
-	if err != nil {
-		return 0, fmt.Errorf("%s must be a duration: %w", key, err)
-	}
-	return parsed, nil
-}