add slice support

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

env.go

@@ -4,12 +4,15 @@ import (
 	"github.com/unistack-org/micro/v3/config"
 	"context"
 	"reflect"
+	"strings"
 	"os"
 	"strconv"
+	"errors"
 )
 
 var (
 	DefaultStructTag = "env"
+	ErrInvalidStruct = errors.New("invalid struct specified")
 )
 
 type envConfig struct {
@@ -29,24 +32,29 @@ func (c *envConfig) Init(opts...config.Option) error {
 }
 
 func (c *envConfig) Load(ctx context.Context) error {
-	fields := reflect.TypeOf(c.opts.Struct).Elem()
+	valueOf := reflect.ValueOf(c.opts.Struct)
-	values := reflect.ValueOf(c.opts.Struct).Elem()
 
-	for idx := 0; idx < fields.NumField(); idx++ {
+	if err := c.fillValues(ctx, valueOf); err != nil {
-		field := fields.Field(idx)
+		return err
-		value := values.Field(idx)
-		if !value.CanSet() {
-			continue
 	}
-		tag, ok := field.Tag.Lookup(c.opts.StructTag)
+
-		if !ok {
+	return nil
-			continue
-		}
-		val, ok := os.LookupEnv(tag)
-		if !ok {
-			continue
 }
+
+func (c *envConfig) fillValue(ctx context.Context, value reflect.Value, val string) error {
 	switch value.Kind() {
+	case reflect.Slice, reflect.Array:
+		nvals := strings.FieldsFunc(val, func(c rune) bool { return c == ',' || c == ';' })
+	//	value = value.Elem()
+		value.Set(reflect.MakeSlice(reflect.SliceOf(value.Type().Elem()), len(nvals), len(nvals)))
+		for idx, nval := range nvals {
+			nvalue := reflect.Indirect(reflect.New(value.Type().Elem()))
+			if err := c.fillValue(ctx, nvalue, nval); err != nil {
+				return err
+			}
+			value.Index(idx).Set(nvalue)
+			//value.Set(reflect.Append(value, nvalue))
+		}
 	case reflect.Bool:
 		v, err := strconv.ParseBool(val)
 		if err != nil {
@@ -60,19 +68,19 @@ func (c *envConfig) Load(ctx context.Context) error {
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(float32(v)))
 	case reflect.Float64:
 		v, err := strconv.ParseFloat(val, 64)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(float64(v)))
 	case reflect.Int:
 		v, err := strconv.ParseInt(val, 10, 0)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(int(v)))
 	case reflect.Int8:
 		v, err := strconv.ParseInt(val, 10, 8)
 		if err != nil {
@@ -84,49 +92,107 @@ func (c *envConfig) Load(ctx context.Context) error {
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(int16(v)))
 	case reflect.Int32:
 		v, err := strconv.ParseInt(val, 10, 32)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(int32(v)))
 	case reflect.Int64:
 		v, err := strconv.ParseInt(val, 10, 64)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(int64(v)))
 	case reflect.Uint:
 		v, err := strconv.ParseUint(val, 10, 0)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(uint(v)))
 	case reflect.Uint8:
 		v, err := strconv.ParseUint(val, 10, 8)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(uint8(v)))
 	case reflect.Uint16:
 		v, err := strconv.ParseUint(val, 10, 16)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(uint16(v)))
 	case reflect.Uint32:
 		v, err := strconv.ParseUint(val, 10, 32)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(uint32(v)))
 	case reflect.Uint64:
 		v, err := strconv.ParseUint(val, 10, 64)
 		if err != nil {
 			return err
 		}
-			value.Set(reflect.ValueOf(v))
+		value.Set(reflect.ValueOf(uint64(v)))
+	}
+	return nil
+}
+
+func (c *envConfig) fillValues(ctx context.Context, valueOf reflect.Value) error {
+	var values reflect.Value
+
+	if valueOf.Kind() == reflect.Ptr {
+		values = valueOf.Elem()
+	} else {
+	values = valueOf
+	}
+
+	if values.Kind() == reflect.Invalid {
+		return ErrInvalidStruct
+	}
+
+	//	if values.Kind() != reflect.Struct {
+	//		return c.fillValue(ctx, values)
+	//	}
+
+	fields := values.Type()
+
+	for idx := 0; idx < fields.NumField(); idx++ {
+		field := fields.Field(idx)
+		value := values.Field(idx)
+		if !value.CanSet() {
+			continue
+		}
+		if len(field.PkgPath) != 0 {
+			continue
+		}
+		if value.Kind() == reflect.Ptr {
+			if value.IsNil() {
+				if value.Type().Elem().Kind() != reflect.Struct {
+					// nil pointer to a non-struct: leave it alone
+					break
+				}
+				// nil pointer to struct: create a zero instance
+				value.Set(reflect.New(value.Type().Elem()))
+			}
+			value = value.Elem()
+			if err := c.fillValues(ctx, value); err != nil {
+				return err
+			}
+			continue
+		}
+		tag, ok := field.Tag.Lookup(c.opts.StructTag)
+		if !ok {
+			return nil
+		}
+		val, ok := os.LookupEnv(tag)
+		if !ok {
+			return nil
+		}
+
+		if err := c.fillValue(ctx, value, val); err != nil {
+			return err
 		}
 	}
 

env_test.go

@@ -6,12 +6,14 @@ import (
 	"testing"
 	"context"
 	"os"
+	"fmt"
 )
 
 type Config struct {
 	StringValue string `env:"STRING_VALUE"`
 	BoolValue bool `env:"BOOL_VALUE"`
 	StringSlice []string `env:"STRING_SLICE"`
+	IntSlice []int `env:"INT_SLICE"`
 }
 
 func TestEnv(t *testing.T) {
@@ -34,7 +36,8 @@ func TestEnv(t *testing.T) {
 
 	os.Setenv("STRING_VALUE","STRING_VALUE")
 	os.Setenv("BOOL_VALUE","true")
-	os.Setenv("STRING_SLICE", "STRING_SLICE1,STRING_SLICE2")
+	os.Setenv("STRING_SLICE", "STRING_SLICE1,STRING_SLICE2;STRING_SLICE3")
+	os.Setenv("INT_SLICE", "1,2,3,4,5")
 
 	if err := cfg.Load(ctx); err !=nil {
 		t.Fatal(err)
@@ -47,7 +50,9 @@ func TestEnv(t *testing.T) {
 		t.Fatalf("something wrong with env config: %v", conf)
 	}
 
-	if len(conf.StringSlice) != 2 {
+	if len(conf.StringSlice) != 3 {
 		t.Fatalf("something wrong with env config: %v", conf)
 	}
+
+	fmt.Printf("%#+v\n", conf)
 }