add parsing for time (#121)

env.go

@@ -7,6 +7,7 @@ import (
 	"reflect"
 	"strconv"
 	"strings"
+	"time"
 
 	"dario.cat/mergo"
 	"go.unistack.org/micro/v4/config"
@@ -50,6 +51,8 @@ func (c *envConfig) Load(ctx context.Context, opts ...config.LoadOption) error {
 
 	options := config.NewLoadOptions(opts...)
 	mopts := []func(*mergo.Config){mergo.WithTypeCheck}
+	tt := timeTransformer{override: options.Override}
+	mopts = append(mopts, mergo.WithTransformers(tt))
 	if options.Override {
 		mopts = append(mopts, mergo.WithOverride)
 	}
@@ -143,7 +146,7 @@ func fillValue(ctx context.Context, value reflect.Value, val string) error {
 		if err != nil {
 			return err
 		}
-		value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(int8(v)))
 	case reflect.Int16:
 		v, err := strconv.ParseInt(val, 10, 16)
 		if err != nil {
@@ -157,6 +160,14 @@ func fillValue(ctx context.Context, value reflect.Value, val string) error {
 		}
 		value.Set(reflect.ValueOf(int32(v)))
 	case reflect.Int64:
+		if value.Type() == reflect.TypeOf(time.Duration(0)) {
+			d, err := time.ParseDuration(val)
+			if err != nil {
+				return fmt.Errorf("cannot parse duration %q: %w", val, err)
+			}
+			value.SetInt(int64(d))
+			return nil
+		}
 		v, err := strconv.ParseInt(val, 10, 64)
 		if err != nil {
 			return err
@@ -217,7 +228,7 @@ func (c *envConfig) setValues(ctx context.Context, valueOf reflect.Value) error
 		if rutil.IsZero(value) {
 			continue
 		}
-		if len(field.PkgPath) != 0 {
+		if !field.IsExported() {
 			continue
 		}
 		switch value.Kind() {
@@ -248,6 +259,20 @@ func (c *envConfig) setValues(ctx context.Context, valueOf reflect.Value) error
 	return nil
 }
 
+func getEnvValue(field reflect.StructField, structTag string) (string, bool) {
+	tags, ok := field.Tag.Lookup(structTag)
+	if !ok {
+		return "", false
+	}
+	var val string
+	for _, tag := range strings.Split(tags, ",") {
+		if v, ok := os.LookupEnv(tag); ok {
+			val = v
+		}
+	}
+	return val, len(val) > 0
+}
+
 func fillValues(ctx context.Context, valueOf reflect.Value, structTag string) error {
 	var values reflect.Value
 
@@ -265,21 +290,42 @@ func fillValues(ctx context.Context, valueOf reflect.Value, structTag string) er
 
 	for idx := 0; idx < fields.NumField(); idx++ {
 		field := fields.Field(idx)
+		if !field.IsExported() {
+			continue
+		}
 		value := values.Field(idx)
 		if !value.CanSet() {
 			continue
 		}
-		if len(field.PkgPath) != 0 {
-			continue
-		}
+
 		switch value.Kind() {
 		case reflect.Struct:
+			if value.Type() == reflect.TypeOf(time.Time{}) {
+				if eval, ok := getEnvValue(field, structTag); ok {
+					parsed, err := time.Parse(time.RFC3339, eval)
+					if err != nil {
+						return fmt.Errorf("cannot parse time.Time %q: %w", eval, err)
+					}
+					value.Set(reflect.ValueOf(parsed))
+				}
+				continue
+			}
 			value.Set(reflect.Indirect(reflect.New(value.Type())))
 			if err := fillValues(ctx, value, structTag); err != nil {
 				return err
 			}
 			continue
 		case reflect.Ptr:
+			if value.Type().Elem() == reflect.TypeOf(time.Time{}) {
+				if eval, ok := getEnvValue(field, structTag); ok {
+					parsed, err := time.Parse(time.RFC3339, eval)
+					if err != nil {
+						return fmt.Errorf("cannot parse *time.Time %q: %w", eval, err)
+					}
+					value.Set(reflect.ValueOf(&parsed))
+				}
+				continue
+			}
 			if value.IsNil() {
 				if value.Type().Elem().Kind() != reflect.Struct {
 					// nil pointer to a non-struct: leave it alone
@@ -288,34 +334,18 @@ func fillValues(ctx context.Context, valueOf reflect.Value, structTag string) er
 				// nil pointer to struct: create a zero instance
 				value.Set(reflect.New(value.Type().Elem()))
 			}
-			value = value.Elem()
-			if err := fillValues(ctx, value, structTag); err != nil {
+			if err := fillValues(ctx, value.Elem(), structTag); err != nil {
 				return err
 			}
 			continue
-		}
-		tags, ok := field.Tag.Lookup(structTag)
-		if !ok {
-			continue
-		}
-
-		var eval string
-		for _, tag := range strings.Split(tags, ",") {
-			if val, ok := os.LookupEnv(tag); !ok {
-				continue
-			} else {
-				eval = val
+		default:
+			if eval, ok := getEnvValue(field, structTag); ok {
+				if err := fillValue(ctx, value, eval); err != nil {
+					return err
+				}
 			}
 		}
-		if eval == "" {
-			continue
-		}
-
-		if err := fillValue(ctx, value, eval); err != nil {
-			return err
-		}
 	}
-
 	return nil
 }
 
@@ -375,3 +405,38 @@ func NewConfig(opts ...config.Option) config.Config {
 	}
 	return &envConfig{opts: options}
 }
+
+type timeTransformer struct {
+	override bool
+}
+
+func (t timeTransformer) Transformer(typ reflect.Type) func(dst, src reflect.Value) error {
+	if typ == reflect.TypeOf(time.Time{}) {
+		return func(dst, src reflect.Value) error {
+			if !dst.CanSet() || src.IsZero() {
+				return nil
+			}
+			if !t.override && !dst.IsZero() {
+				return nil
+			}
+			dst.Set(src)
+			return nil
+		}
+	}
+	if typ == reflect.TypeOf((*time.Time)(nil)) {
+		return func(dst, src reflect.Value) error {
+			if !dst.CanSet() || src.IsNil() {
+				return nil
+			}
+			if src.Elem().IsZero() {
+				return nil
+			}
+			if !t.override && !dst.IsNil() && !dst.Elem().IsZero() {
+				return nil
+			}
+			dst.Set(src)
+			return nil
+		}
+	}
+	return nil
+}

env_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/stretchr/testify/require"
 	"go.unistack.org/micro/v4/config"
 	rutil "go.unistack.org/micro/v4/util/reflect"
 )
@@ -238,3 +239,336 @@ func TestLoadMultiple(t *testing.T) {
 		}
 	}
 }
+
+func TestEnv_SupportedTypes(t *testing.T) {
+	type Config struct {
+		IntValue   int   `env:"INT_VALUE"`
+		Int8Value  int8  `env:"INT8_VALUE"`
+		Int16Value int16 `env:"INT16_VALUE"`
+		Int32Value int32 `env:"INT32_VALUE"`
+		Int64Value int64 `env:"INT64_VALUE"`
+
+		UintValue   uint   `env:"UINT_VALUE"`
+		Uint8Value  uint8  `env:"UINT8_VALUE"`
+		Uint16Value uint16 `env:"UINT16_VALUE"`
+		Uint32Value uint32 `env:"UINT32_VALUE"`
+		Uint64Value uint64 `env:"UINT64_VALUE"`
+
+		Float32Value float32 `env:"FLOAT32_VALUE"`
+		Float64Value float64 `env:"FLOAT64_VALUE"`
+
+		BoolValue bool `env:"BOOL_VALUE"`
+
+		StringValue string `env:"STRING_VALUE"`
+
+		StringSlice []string `env:"STRING_SLICE"`
+		IntSlice    []int    `env:"INT_SLICE"`
+
+		MapStringValue map[string]string `env:"MAP_STRING"`
+		MapIntValue    map[string]int    `env:"MAP_INT"`
+
+		DurationValue time.Duration `env:"DURATION_VALUE"`
+		TimeValue     time.Time     `env:"TIME_VALUE"`
+		TimePtrValue  *time.Time    `env:"TIME_PTR_VALUE"`
+	}
+
+	tests := []struct {
+		name   string
+		envVar string
+		envVal string
+		want   func() *Config
+	}{
+		// integers
+		{
+			name:   "int type",
+			envVar: "INT_VALUE",
+			envVal: "100",
+			want:   func() *Config { return &Config{IntValue: 100} },
+		},
+		{
+			name:   "int8 type",
+			envVar: "INT8_VALUE",
+			envVal: "127",
+			want:   func() *Config { return &Config{Int8Value: 127} },
+		},
+		{
+			name:   "int16 type",
+			envVar: "INT16_VALUE",
+			envVal: "32767",
+			want:   func() *Config { return &Config{Int16Value: 32767} },
+		},
+		{
+			name:   "int32 type",
+			envVar: "INT32_VALUE",
+			envVal: "2147483647",
+			want:   func() *Config { return &Config{Int32Value: 2147483647} },
+		},
+		{
+			name:   "int64 type",
+			envVar: "INT64_VALUE",
+			envVal: "9223372036854775807",
+			want:   func() *Config { return &Config{Int64Value: 9223372036854775807} },
+		},
+		// unsigned integers
+		{
+			name:   "uint type",
+			envVar: "UINT_VALUE",
+			envVal: "100",
+			want:   func() *Config { return &Config{UintValue: 100} },
+		},
+		{
+			name:   "uint8 type",
+			envVar: "UINT8_VALUE",
+			envVal: "255",
+			want:   func() *Config { return &Config{Uint8Value: 255} },
+		},
+		{
+			name:   "uint16 type",
+			envVar: "UINT16_VALUE",
+			envVal: "65535",
+			want:   func() *Config { return &Config{Uint16Value: 65535} },
+		},
+		{
+			name:   "uint32 type",
+			envVar: "UINT32_VALUE",
+			envVal: "4294967295",
+			want:   func() *Config { return &Config{Uint32Value: 4294967295} },
+		},
+		{
+			name:   "uint64 type",
+			envVar: "UINT64_VALUE",
+			envVal: "18446744073709551615",
+			want:   func() *Config { return &Config{Uint64Value: 18446744073709551615} },
+		},
+		// floats
+		{
+			name:   "float32 type",
+			envVar: "FLOAT32_VALUE",
+			envVal: "3.14159",
+			want:   func() *Config { return &Config{Float32Value: 3.14159} },
+		},
+		{
+			name:   "float64 type",
+			envVar: "FLOAT64_VALUE",
+			envVal: "3.141592653589793",
+			want:   func() *Config { return &Config{Float64Value: 3.141592653589793} },
+		},
+		// bool
+		{
+			name:   "bool true",
+			envVar: "BOOL_VALUE",
+			envVal: "true",
+			want:   func() *Config { return &Config{BoolValue: true} },
+		},
+		{
+			name:   "bool false",
+			envVar: "BOOL_VALUE",
+			envVal: "false",
+			want:   func() *Config { return &Config{BoolValue: false} },
+		},
+		{
+			name:   "bool 1",
+			envVar: "BOOL_VALUE",
+			envVal: "1",
+			want:   func() *Config { return &Config{BoolValue: true} },
+		},
+		{
+			name:   "bool 0",
+			envVar: "BOOL_VALUE",
+			envVal: "0",
+			want:   func() *Config { return &Config{BoolValue: false} },
+		},
+		// string
+		{
+			name:   "string type",
+			envVar: "STRING_VALUE",
+			envVal: "hello world",
+			want:   func() *Config { return &Config{StringValue: "hello world"} },
+		},
+		// slices
+		{
+			name:   "string slice comma separated",
+			envVar: "STRING_SLICE",
+			envVal: "val1,val2,val3",
+			want:   func() *Config { return &Config{StringSlice: []string{"val1", "val2", "val3"}} },
+		},
+		{
+			name:   "string slice semicolon separated",
+			envVar: "STRING_SLICE",
+			envVal: "val1;val2;val3",
+			want:   func() *Config { return &Config{StringSlice: []string{"val1", "val2", "val3"}} },
+		},
+		{
+			name:   "int slice comma separated",
+			envVar: "INT_SLICE",
+			envVal: "1,2,3,4,5",
+			want:   func() *Config { return &Config{IntSlice: []int{1, 2, 3, 4, 5}} },
+		},
+		{
+			name:   "int slice semicolon separated",
+			envVar: "INT_SLICE",
+			envVal: "1;2;3;4;5",
+			want:   func() *Config { return &Config{IntSlice: []int{1, 2, 3, 4, 5}} },
+		},
+		// maps
+		{
+			name:   "string map",
+			envVar: "MAP_STRING",
+			envVal: "key1=val1,key2=val2",
+			want: func() *Config {
+				return &Config{MapStringValue: map[string]string{"key1": "val1", "key2": "val2"}}
+			},
+		},
+		{
+			name:   "int map",
+			envVar: "MAP_INT",
+			envVal: "key1=1,key2=2",
+			want: func() *Config {
+				return &Config{MapIntValue: map[string]int{"key1": 1, "key2": 2}}
+			},
+		},
+		// time && duration
+		{
+			name:   "duration type",
+			envVar: "DURATION_VALUE",
+			envVal: "15m30s",
+			want:   func() *Config { return &Config{DurationValue: 15*time.Minute + 30*time.Second} },
+		},
+		{
+			name:   "time type RFC3339",
+			envVar: "TIME_VALUE",
+			envVal: "2025-08-28T15:04:05Z",
+			want: func() *Config {
+				return &Config{TimeValue: time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC)}
+			},
+		},
+		{
+			name:   "time type RFC3339",
+			envVar: "TIME_PTR_VALUE",
+			envVal: "2025-08-28T15:04:05Z",
+			want: func() *Config {
+				timeValue := time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC)
+				return &Config{TimePtrValue: &timeValue}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			require.NoError(t, os.Setenv(tt.envVar, tt.envVal))
+			defer os.Unsetenv(tt.envVar)
+
+			cfgData := &Config{}
+			cfg := NewConfig(config.Struct(cfgData))
+
+			require.NoError(t, cfg.Init())
+			require.NoError(t, cfg.Load(context.Background()))
+
+			require.Equal(t, tt.want(), cfgData)
+		})
+	}
+}
+
+func TestEnv_TimeType_Override(t *testing.T) {
+	type Config struct {
+		TimeValue time.Time `env:"TIME"`
+	}
+
+	tests := []struct {
+		name   string
+		cfg    *Config
+		envVar string
+		envVal string
+		want   *Config
+	}{
+		{
+			name:   "init value is empty",
+			cfg:    &Config{},
+			envVar: "TIME",
+			envVal: "2025-08-28T15:04:05Z",
+			want: &Config{
+				TimeValue: time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC),
+			},
+		},
+		{
+			name: "init value is not empty",
+			cfg: &Config{
+				TimeValue: time.Date(2025, 5, 25, 15, 5, 5, 5, time.UTC),
+			},
+			envVar: "TIME",
+			envVal: "2025-08-28T15:04:05Z",
+			want: &Config{
+				TimeValue: time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC),
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			require.NoError(t, os.Setenv(tt.envVar, tt.envVal))
+			defer os.Unsetenv(tt.envVar)
+
+			cfg := NewConfig(config.Struct(tt.cfg))
+			require.NoError(t, cfg.Init())
+			require.NoError(t, cfg.Load(context.Background(), config.LoadOverride(true)))
+			require.Equal(t, tt.want, tt.cfg)
+		})
+	}
+}
+
+func TestEnv_TimePointerType_Override(t *testing.T) {
+	type Config struct {
+		TimeValue *time.Time `env:"TIME"`
+	}
+
+	tests := []struct {
+		name   string
+		cfg    func() *Config
+		envVar string
+		envVal string
+		want   func() *Config
+	}{
+		{
+			name:   "init value is empty",
+			cfg:    func() *Config { return &Config{} },
+			envVar: "TIME",
+			envVal: "2025-08-28T15:04:05Z",
+			want: func() *Config {
+				timeValue := time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC)
+				return &Config{
+					TimeValue: &timeValue,
+				}
+			},
+		},
+		{
+			name: "init value is not empty",
+			cfg: func() *Config {
+				timeValue := time.Date(2025, 5, 25, 15, 5, 5, 5, time.UTC)
+				return &Config{
+					TimeValue: &timeValue,
+				}
+			},
+			envVar: "TIME",
+			envVal: "2025-08-28T15:04:05Z",
+			want: func() *Config {
+				timeValue := time.Date(2025, 8, 28, 15, 4, 5, 0, time.UTC)
+				return &Config{
+					TimeValue: &timeValue,
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			require.NoError(t, os.Setenv(tt.envVar, tt.envVal))
+			defer os.Unsetenv(tt.envVar)
+
+			cfgData := tt.cfg()
+			cfg := NewConfig(config.Struct(cfgData))
+			require.NoError(t, cfg.Init())
+			require.NoError(t, cfg.Load(context.Background(), config.LoadOverride(true)))
+			require.Equal(t, tt.want(), cfgData)
+		})
+	}
+}

go.mod

@@ -9,12 +9,18 @@ require (
 	go.unistack.org/micro/v4 v4.1.3
 )
 
+require (
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
+)
+
 require (
 	github.com/ash3in/uuidv8 v1.2.0 // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/matoous/go-nanoid v1.5.1 // indirect
 	github.com/spf13/cast v1.7.1 // indirect
+	github.com/stretchr/testify v1.11.1
 	go.unistack.org/micro-proto/v4 v4.1.0 // indirect
 	google.golang.org/protobuf v1.36.5 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/DATA-DOG/go-sqlmock v1.5.2 h1:OcvFkGmslmlZibjAjaHm3L//6LiuBgolP7Oputl
 github.com/DATA-DOG/go-sqlmock v1.5.2/go.mod h1:88MAG/4G7SMwSE3CeA0ZKzrT5CiOU3OJ+JlNzwDqpNU=
 github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
 github.com/ash3in/uuidv8 v1.2.0/go.mod h1:BnU0wJBxnzdEKmVg4xckBkD+VZuecTFTUP3M0dWgyY4=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
 github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
@@ -16,16 +18,18 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/matoous/go-nanoid v1.5.1 h1:aCjdvTyO9LLnTIi0fgdXhOPPvOHjpXN6Ik9DaNjIct4=
 github.com/matoous/go-nanoid v1.5.1/go.mod h1:zyD2a71IubI24efhpvkJz+ZwfwagzgSO6UNiFsZKN7U=
+github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
+github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
 github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
 github.com/spf13/cast v1.7.1 h1:cuNEagBQEHWN1FnbGEjCXL2szYEXqfJPbP2HNUaca9Y=
 github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 go.unistack.org/micro-proto/v4 v4.1.0 h1:qPwL2n/oqh9RE3RTTDgt28XK3QzV597VugQPaw9lKUk=
 go.unistack.org/micro-proto/v4 v4.1.0/go.mod h1:ArmK7o+uFvxSY3dbJhKBBX4Pm1rhWdLEFf3LxBrMtec=
 go.unistack.org/micro/v4 v4.1.3 h1:9QHiLHBTfPtfKyoY3HsLPNVSK0wlAAoMV+9saLz2iR4=
 go.unistack.org/micro/v4 v4.1.3/go.mod h1:lr3oYED8Ay1vjK68QqRw30QOtdk/ffpZqMFDasOUhKw=
-google.golang.org/protobuf v1.36.3 h1:82DV7MYdb8anAVi3qge1wSnMDrnKK7ebr+I0hHRN1BU=
-google.golang.org/protobuf v1.36.3/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 google.golang.org/protobuf v1.36.5 h1:tPhr+woSbjfYvY6/GPufUoYizxw1cF/yFoxJ2fmpwlM=
 google.golang.org/protobuf v1.36.5/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=