cmd/frostfs-node/config/config.go

@@ -14,7 +14,9 @@ import (
 type Config struct {
 	v *viper.Viper
 
-	opts configViper.Opts
+	configFile string
+	configDir  string
+	envPrefix  string
 
 	defaultPath []string
 	path        []string
@@ -28,23 +30,31 @@ const (
 
 // New creates a new Config instance.
 //
-// If file option is provided (WithConfigFile),
+// If file option is provided,
 // configuration values are read from it.
 // Otherwise, Config is a degenerate tree.
-func New(opts ...configViper.Option) *Config {
-	v, o, err := configViper.CreateViper(opts...)
+func New(configFile, configDir, envPrefix string) *Config {
+	v, err := configViper.CreateViper(
+		configViper.WithConfigFile(configFile),
+		configViper.WithConfigDir(configDir),
+		configViper.WithEnvPrefix(envPrefix))
 
 	if err != nil {
 		panic(err)
 	}
 
 	return &Config{
-		v:    v,
-		opts: *o,
+		v:          v,
+		configFile: configFile,
+		configDir:  configDir,
+		envPrefix:  envPrefix,
 	}
 }
 
 // Reload reads configuration path if it was provided to New.
 func (x *Config) Reload() error {
-	return configViper.ReloadViper(x.v, x.opts)
+	return configViper.ReloadViper(
+		configViper.WithViper(x.v), configViper.WithConfigFile(x.configFile),
+		configViper.WithConfigDir(x.configDir),
+		configViper.WithEnvPrefix(x.envPrefix))
 }

cmd/frostfs-node/config/configdir_test.go

@@ -5,7 +5,6 @@ import (
 	"path"
 	"testing"
 
-	configViper "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/internal/common/config"
 	"github.com/spf13/cast"
 	"github.com/stretchr/testify/require"
 )
@@ -19,7 +18,7 @@ func TestConfigDir(t *testing.T) {
 	require.NoError(t, os.WriteFile(cfgFileName0, []byte(`{"storage":{"shard_pool_size":15}}`), 0777))
 	require.NoError(t, os.WriteFile(cfgFileName1, []byte("logger:\n  level: debug"), 0777))
 
-	c := New(configViper.WithConfigDir(dir))
+	c := New("", dir, "")
 	require.Equal(t, "debug", cast.ToString(c.Sub("logger").Value("level")))
 	require.EqualValues(t, 15, cast.ToUint32(c.Sub("storage").Value("shard_pool_size")))
 }

cmd/frostfs-node/config/test/config.go

@@ -7,22 +7,19 @@ import (
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/cmd/frostfs-node/config"
-	configViper "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/internal/common/config"
 	"github.com/stretchr/testify/require"
 )
 
 func fromFile(path string) *config.Config {
 	os.Clearenv() // ENVs have priority over config files, so we do this in tests
 
-	return config.New(
-		configViper.WithConfigFile(path),
-	)
+	return config.New(path, "", "")
 }
 
 func fromEnvFile(t testing.TB, path string) *config.Config {
 	loadEnv(t, path) // github.com/joho/godotenv can do that as well
 
-	return config.New(configViper.WithEnvPrefix(config.EnvPrefix))
+	return config.New("", "", config.EnvPrefix)
 }
 
 func forEachFile(paths []string, f func(*config.Config)) {
@@ -48,7 +45,7 @@ func ForEnvFileType(t testing.TB, pref string, f func(*config.Config)) {
 
 // EmptyConfig returns config without any values and sections.
 func EmptyConfig() *config.Config {
-	return config.New(configViper.WithEnvPrefix(config.EnvPrefix))
+	return config.New("", "", config.EnvPrefix)
 }
 
 // loadEnv reads .env file, parses `X=Y` records and sets OS ENVs.

cmd/frostfs-node/main.go

@@ -8,7 +8,6 @@ import (
 	"os"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/cmd/frostfs-node/config"
-	configViper "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/internal/common/config"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/misc"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/services/control"
@@ -47,9 +46,7 @@ func main() {
 		os.Exit(SuccessReturnCode)
 	}
 
-	appCfg := config.New(
-		configViper.WithConfigFile(*configFile), configViper.WithConfigDir(*configDir),
-		configViper.WithEnvPrefix(config.EnvPrefix))
+	appCfg := config.New(*configFile, *configDir, config.EnvPrefix)
 
 	err := validateConfig(appCfg)
 	fatalOnErr(err)

cmd/frostfs-node/validate_test.go

@@ -7,7 +7,6 @@ import (
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/cmd/frostfs-node/config"
 	configtest "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/frostfs-node/config/test"
-	configViper "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/internal/common/config"
 	"github.com/stretchr/testify/require"
 )
 
@@ -27,13 +26,13 @@ func TestValidate(t *testing.T) {
 	t.Run("mainnet", func(t *testing.T) {
 		os.Clearenv() // ENVs have priority over config files, so we do this in tests
 		p := filepath.Join(exampleConfigPrefix, "mainnet/config.yml")
-		c := config.New(configViper.WithConfigFile(p))
+		c := config.New(p, "", config.EnvPrefix)
 		require.NoError(t, validateConfig(c))
 	})
 	t.Run("testnet", func(t *testing.T) {
 		os.Clearenv() // ENVs have priority over config files, so we do this in tests
 		p := filepath.Join(exampleConfigPrefix, "testnet/config.yml")
-		c := config.New(configViper.WithConfigFile(p))
+		c := config.New(p, "", config.EnvPrefix)
 		require.NoError(t, validateConfig(c))
 	})
 }

cmd/internal/common/config/opts.go

@@ -1,38 +1,49 @@
 package config
 
-type Opts struct {
-	Path      string
-	ConfigDir string
-	EnvPrefix string
+import "github.com/spf13/viper"
+
+type opts struct {
+	path      string
+	configDir string
+	envPrefix string
+	v         *viper.Viper
 }
 
-func DefaultOpts() *Opts {
-	return new(Opts)
+func defaultOpts() *opts {
+	return new(opts)
 }
 
 // Option allows to set an optional parameter of the Config.
-type Option func(*Opts)
+type Option func(*opts)
 
 // WithConfigFile returns an option to set the system path
 // to the configuration file.
 func WithConfigFile(path string) Option {
-	return func(o *Opts) {
-		o.Path = path
+	return func(o *opts) {
+		o.path = path
 	}
 }
 
 // WithConfigDir returns an option to set the system path
 // to the directory with configuration files.
 func WithConfigDir(path string) Option {
-	return func(o *Opts) {
-		o.ConfigDir = path
+	return func(o *opts) {
+		o.configDir = path
 	}
 }
 
 // WithEnvPrefix returns an option to defines
 // a prefix that ENVIRONMENT variables will use.
 func WithEnvPrefix(envPrefix string) Option {
-	return func(o *Opts) {
-		o.EnvPrefix = envPrefix
+	return func(o *opts) {
+		o.envPrefix = envPrefix
+	}
+}
+
+// WithViper returns an option to defines
+// a predefined viper.Viper.
+func WithViper(v *viper.Viper) Option {
+	return func(o *opts) {
+		o.v = v
 	}
 }

cmd/internal/common/config/viper.go

@@ -15,48 +15,62 @@ const (
 	EnvSeparator = "_"
 )
 
-func CreateViper(opts ...Option) (*viper.Viper, *Opts, error) {
-	v := viper.New()
-
-	o := DefaultOpts()
+func CreateViper(opts ...Option) (*viper.Viper, error) {
+	o := defaultOpts()
 	for i := range opts {
 		opts[i](o)
 	}
 
-	if o.EnvPrefix != "" {
-		v.SetEnvPrefix(o.EnvPrefix)
+	var v *viper.Viper
+	if o.v != nil {
+		v = o.v
+	} else {
+		v = viper.New()
+	}
+
+	if o.envPrefix != "" {
+		v.SetEnvPrefix(o.envPrefix)
 		v.AutomaticEnv()
 		v.SetEnvKeyReplacer(strings.NewReplacer(Separator, EnvSeparator))
 	}
 
-	if o.Path != "" {
-		v.SetConfigFile(o.Path)
+	if o.path != "" {
+		v.SetConfigFile(o.path)
 
 		err := v.ReadInConfig()
 		if err != nil {
-			return nil, nil, fmt.Errorf("failed to read config: %w", err)
+			return nil, fmt.Errorf("failed to read config: %w", err)
 		}
 	}
 
-	if o.ConfigDir != "" {
-		if err := config.ReadConfigDir(v, o.ConfigDir); err != nil {
-			return nil, nil, fmt.Errorf("failed to read config dir: %w", err)
+	if o.configDir != "" {
+		if err := config.ReadConfigDir(v, o.configDir); err != nil {
+			return nil, fmt.Errorf("failed to read config dir: %w", err)
 		}
 	}
 
-	return v, o, nil
+	return v, nil
 }
 
-func ReloadViper(v *viper.Viper, o Opts) error {
-	if o.Path != "" {
-		err := v.ReadInConfig()
+func ReloadViper(opts ...Option) error {
+	o := defaultOpts()
+	for i := range opts {
+		opts[i](o)
+	}
+
+	if o.v == nil {
+		return fmt.Errorf("provide viper in opts")
+	}
+
+	if o.path != "" {
+		err := o.v.ReadInConfig()
 		if err != nil {
 			return fmt.Errorf("rereading configuration file: %w", err)
 		}
 	}
 
-	if o.ConfigDir != "" {
-		if err := config.ReadConfigDir(v, o.ConfigDir); err != nil {
+	if o.configDir != "" {
+		if err := config.ReadConfigDir(o.v, o.configDir); err != nil {
 			return fmt.Errorf("rereading configuration dir: %w", err)
 		}
 	}