feat: minor adjustments (cba)

codec/yaml.go

@@ -5,8 +5,9 @@ import (
 	"fmt"
 	"reflect"
 
-	"github.com/lukasjarosch/skipper/data"
 	"gopkg.in/yaml.v3"
+
+	"github.com/lukasjarosch/skipper/data"
 )
 
 type YamlCodec struct{}
@@ -15,8 +16,8 @@ func NewYamlCodec() YamlCodec {
 	return YamlCodec{}
 }
 
-func (codec YamlCodec) Unmarshal(in []byte) (data.Map, error) {
-	var out data.Map
+func (codec YamlCodec) Unmarshal(in []byte) (map[string]interface{}, error) {
+	var out map[string]interface{}
 	err := codec.UnmarshalTarget(in, &out)
 	if err != nil {
 		return nil, err
@@ -48,13 +49,13 @@ func (codec YamlCodec) UnmarshalPath(in []byte, path data.Path, target interface
 		return fmt.Errorf("cannot decode with path: target must be a pointer")
 	}
 
-	var out data.Map
+	var out map[string]interface{}
 	err := yaml.Unmarshal(in, &out)
 	if err != nil {
 		return err
 	}
 
-	tree, err := out.Get(path)
+	tree, err := data.Get(out, path.String())
 	if err != nil {
 		return err
 	}

data/container.go

@@ -18,7 +18,7 @@ var (
 // The data can have only one key, which must match the container name.
 // So a container named 'foo' must have data like 'map[string]interface{"foo": ....}'
 type Container struct {
-	name string
+	Name string
 	data map[string]interface{}
 }
 
@@ -66,7 +66,7 @@ func NewContainer(name string, data map[string]interface{}) (*Container, error)
 	}
 
 	c := &Container{
-		name: name,
+		Name: name,
 		data: data,
 	}
 
@@ -88,8 +88,8 @@ func (container *Container) Get(path Path) (Value, error) {
 	}
 
 	// make sure the path is absolute and contains the container name as first segment (aka root key)
-	if path.First() != container.name {
-		path = path.Prepend(container.name)
+	if path.First() != container.Name {
+		path = path.Prepend(container.Name)
 	}
 
 	ret, err := DeepGet(container.data, []string(path))
@@ -121,8 +121,8 @@ func (container *Container) Set(path Path, value interface{}) error {
 	}
 
 	// ensure path is absolute
-	if path.First() != container.name {
-		path = path.Prepend(container.name)
+	if path.First() != container.Name {
+		path = path.Prepend(container.Name)
 	}
 
 	ret, err := DeepSet(container.data, path, value)

data/data.go

@@ -12,7 +12,7 @@ var (
 	ErrInvalidValue              = fmt.Errorf("invalid value")
 	ErrUnsupportedDataType       = fmt.Errorf("unsupported data type")
 	ErrNegativeIndex             = fmt.Errorf("negative index")
-	ErrTypeChange                = fmt.Errorf("changing types is not supported")
+	ErrTypeChange                = fmt.Errorf("changing data-types is not supported")
 )
 
 type WalkFunc func(path Path, data interface{}, isLeaf bool) error
@@ -28,7 +28,7 @@ func walk(parent interface{}, path Path, walkFn WalkFunc) error {
 		return nil
 	}
 
-	var parentValue = reflect.ValueOf(parent)
+	parentValue := reflect.ValueOf(parent)
 
 	switch parentValue.Kind() {
 	case reflect.Map:
@@ -108,14 +108,14 @@ func DeepGet(data interface{}, path Path) (interface{}, error) {
 	current := ResolveValue(data)
 
 	for i := 0; i < len(path); i++ {
-		var pathSegment = path[i]
-		var curValue = reflect.ValueOf(current)
+		pathSegment := path[i]
+		curValue := reflect.ValueOf(current)
 
 		if !curValue.IsValid() {
 			return nil, ErrInvalidValue
 		}
 
-		var curTyp = curValue.Type()
+		curTyp := curValue.Type()
 
 		// for pointers and interfaces, get the underlying type
 		switch curValue.Kind() {
@@ -308,8 +308,14 @@ func DeepSet(data interface{}, path Path, value interface{}) (interface{}, error
 		// value by evaluating the currentSegment just as above.
 		// But allowing to change scalar types would also mean that
 		// we should allow changing []interface{} to map[string]interface{}.
-		// Hence we simply don't allow chaning types at the moment.
-		return nil, ErrTypeChange
+		// This would introduce even more complexity because there might exist a []interface{1, 2, 3}
+		// which must then suddenly be mapped to map[string]interface{"0": 1, "1": 2, "2": 3}.
+		// This will also introduce side-effects which the user most likely does not expect.
+		// Hence we simply don't allow changing types at the moment.
+		//
+		// Additionally, dynamic data-type changes would not work once a user wants to
+		// use a schema with the data.
+		return nil, fmt.Errorf("cannot set path segment '%s': %w", path, ErrTypeChange)
 	}
 }
 
@@ -343,7 +349,7 @@ func Merge(baseData map[string]interface{}, mergeData map[string]interface{}) ma
 }
 
 func Keys(input interface{}) []interface{} {
-	var keys = make([]interface{}, 0)
+	keys := make([]interface{}, 0)
 
 	if input == nil {
 		return keys
@@ -370,6 +376,7 @@ type PathSelectorFunc func(data interface{}, path Path, isLeaf bool) bool
 var SelectAllPaths PathSelectorFunc = func(_ interface{}, path Path, isLeaf bool) bool {
 	return true
 }
+
 var SelectLeafPaths PathSelectorFunc = func(_ interface{}, path Path, isLeaf bool) bool {
 	if isLeaf {
 		return true

data/reflect.go

@@ -105,7 +105,7 @@ func IsInteger(in interface{}) bool {
 	return false
 }
 
-// Dectect whether the concrete underlying value of the given input is one or more
+// Detect whether the concrete underlying value of the given input is one or more
 // Kinds of value.
 func IsKind(in interface{}, kinds ...reflect.Kind) bool {
 	var inT reflect.Type

data/value.go

@@ -5,7 +5,9 @@ import (
 	"time"
 )
 
-// Value represents a generic value that originates fom [Data]
+var NilValue = Value{Raw: nil}
+
+// Value represents a generic value that originates from the underlying data.
 type Value struct {
 	Raw interface{}
 }