feat(core): add argspec util to get corresponding type from argstype (#2850)

Author: Codelax

internal/core/arg_specs.go

@@ -3,9 +3,11 @@ package core
 import (
 	"context"
 	"fmt"
+	"reflect"
 	"strings"
 
 	"github.com/scaleway/scaleway-sdk-go/scw"
+	"github.com/scaleway/scaleway-sdk-go/strcase"
 	"github.com/scaleway/scaleway-sdk-go/validation"
 )
 
@@ -119,6 +121,13 @@ func (a *ArgSpec) ConflictWith(b *ArgSpec) bool {
 		(a.OneOfGroup == b.OneOfGroup)
 }
 
+// GetArgsTypeField returns the type of the argument in the given ArgsType
+func (a *ArgSpec) GetArgsTypeField(argsType reflect.Type) (reflect.Type, error) {
+	argSpecGoName := strcase.ToPublicGoName(a.Name)
+
+	return getTypeForFieldByName(argsType, strings.Split(argSpecGoName, "."))
+}
+
 type DefaultFunc func(ctx context.Context) (value string, doc string)
 
 func ZoneArgSpec(zones ...scw.Zone) *ArgSpec {

internal/core/arg_specs_test.go

@@ -1,6 +1,7 @@
 package core
 
 import (
+	"reflect"
 	"testing"
 
 	"github.com/alecthomas/assert"
@@ -36,3 +37,35 @@ func TestOneOf(t *testing.T) {
 	assert.False(t, a.ConflictWith(c))
 	assert.False(t, e.ConflictWith(e))
 }
+
+func TestArgSpecGetArgsTypeField(t *testing.T) {
+	data := struct {
+		Field       string
+		FieldStruct struct {
+			NestedField int
+		}
+		FieldSlice []float32
+		FieldMap   map[string]bool
+	}{}
+	dataType := reflect.TypeOf(data)
+
+	fieldSpec := ArgSpec{Name: "field"}
+	typ, err := fieldSpec.GetArgsTypeField(dataType)
+	assert.Nil(t, err)
+	assert.Equal(t, reflect.TypeOf("string"), typ, "%s is not string", typ.Name())
+
+	fieldSpec = ArgSpec{Name: "field-struct.nested-field"}
+	typ, err = fieldSpec.GetArgsTypeField(dataType)
+	assert.Nil(t, err)
+	assert.Equal(t, reflect.TypeOf(int(1)), typ, "%s is not int", typ.Name())
+
+	fieldSpec = ArgSpec{Name: "field-slice.{index}"}
+	typ, err = fieldSpec.GetArgsTypeField(dataType)
+	assert.Nil(t, err)
+	assert.Equal(t, reflect.TypeOf(float32(1)), typ, "%s is not float32", typ.Name())
+
+	fieldSpec = ArgSpec{Name: "field-map.{key}"}
+	typ, err = fieldSpec.GetArgsTypeField(dataType)
+	assert.Nil(t, err)
+	assert.Equal(t, reflect.TypeOf(true), typ, "%s is not bool", typ.Name())
+}

internal/core/reflect.go

@@ -109,3 +109,32 @@ func getValuesForFieldByName(value reflect.Value, parts []string) (values []refl
 
 	return nil, fmt.Errorf("case is not handled")
 }
+
+// getTypeForFieldByName recursively search for fields in an ArgsType
+// The search is based on the name of the field.
+func getTypeForFieldByName(value reflect.Type, parts []string) (reflect.Type, error) {
+	if len(parts) == 0 {
+		return value, nil
+	}
+
+	switch value.Kind() {
+	case reflect.Ptr:
+		return getTypeForFieldByName(value.Elem(), parts)
+
+	case reflect.Slice:
+		return getTypeForFieldByName(value.Elem(), parts[1:])
+
+	case reflect.Map:
+		return getTypeForFieldByName(value.Elem(), parts[1:])
+
+	case reflect.Struct:
+		fieldName := strcase.ToPublicGoName(parts[0])
+		field, hasField := value.FieldByName(fieldName)
+		if !hasField {
+			return nil, fmt.Errorf("field %v does not exist for %v", fieldName, value.Name())
+		}
+		return getTypeForFieldByName(field.Type, parts[1:])
+	}
+
+	return nil, fmt.Errorf("type kind %s is not handled", value.Kind().String())
+}