[chore] [pkg/ottl] Introduce ctxutil.GetMap() and ctxutil.GetMapKeyName() internal functions

pkg/ottl/contexts/internal/ctxutil/map.go

@@ -18,16 +18,9 @@ func GetMapValue[K any](ctx context.Context, tCtx K, m pcommon.Map, keys []ottl.
 		return nil, errors.New("cannot get map value without keys")
 	}
 
-	s, err := keys[0].String(ctx, tCtx)
+	s, err := GetMapKeyName(ctx, tCtx, keys[0])
 	if err != nil {
-		return nil, err
-	}
-	if s == nil {
-		resString, err := FetchValueFromExpression[K, string](ctx, tCtx, keys[0])
-		if err != nil {
-			return nil, fmt.Errorf("unable to resolve a string index in map: %w", err)
-		}
-		s = resString
+		return nil, fmt.Errorf("cannot get map value: %w", err)
 	}
 
 	val, ok := m.Get(*s)
@@ -40,19 +33,12 @@ func GetMapValue[K any](ctx context.Context, tCtx K, m pcommon.Map, keys []ottl.
 
 func SetMapValue[K any](ctx context.Context, tCtx K, m pcommon.Map, keys []ottl.Key[K], val any) error {
 	if len(keys) == 0 {
-		return errors.New("cannot set map value without key")
+		return errors.New("cannot set map value without keys")
 	}
 
-	s, err := keys[0].String(ctx, tCtx)
+	s, err := GetMapKeyName(ctx, tCtx, keys[0])
 	if err != nil {
-		return err
-	}
-	if s == nil {
-		resString, err := FetchValueFromExpression[K, string](ctx, tCtx, keys[0])
-		if err != nil {
-			return fmt.Errorf("unable to resolve a string index in map: %w", err)
-		}
-		s = resString
+		return fmt.Errorf("cannot set map value: %w", err)
 	}
 
 	currentValue, ok := m.Get(*s)
@@ -62,6 +48,20 @@ func SetMapValue[K any](ctx context.Context, tCtx K, m pcommon.Map, keys []ottl.
 	return SetIndexableValue[K](ctx, tCtx, currentValue, val, keys[1:])
 }
 
+func GetMapKeyName[K any](ctx context.Context, tCtx K, key ottl.Key[K]) (*string, error) {
+	resolvedKey, err := key.String(ctx, tCtx)
+	if err != nil {
+		return nil, err
+	}
+	if resolvedKey == nil {
+		resolvedKey, err = FetchValueFromExpression[K, string](ctx, tCtx, key)
+		if err != nil {
+			return nil, fmt.Errorf("unable to resolve a string index in map: %w", err)
+		}
+	}
+	return resolvedKey, nil
+}
+
 func FetchValueFromExpression[K any, T int64 | string](ctx context.Context, tCtx K, key ottl.Key[K]) (*T, error) {
 	p, err := key.ExpressionGetter(ctx, tCtx)
 	if err != nil {
@@ -89,5 +89,19 @@ func SetMap(target pcommon.Map, val any) error {
 	if rm, ok := val.(map[string]any); ok {
 		return target.FromRaw(rm)
 	}
-	return nil
+	return fmt.Errorf("failed to convert type %T into pcommon.Map", val)
+}
+
+func GetMap(val any) (pcommon.Map, error) {
+	if m, ok := val.(pcommon.Map); ok {
+		return m, nil
+	}
+	if rm, ok := val.(map[string]any); ok {
+		m := pcommon.NewMap()
+		if err := m.FromRaw(rm); err != nil {
+			return pcommon.Map{}, err
+		}
+		return m, nil
+	}
+	return pcommon.Map{}, fmt.Errorf("failed to convert type %T into pcommon.Map", val)
 }

pkg/ottl/contexts/internal/ctxutil/map_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
@@ -39,7 +40,7 @@ func Test_GetMapValue_Invalid(t *testing.T) {
 					G: getSetter,
 				},
 			},
-			err: errors.New("unable to resolve a string index in map: could not resolve key for map/slice, expecting 'string' but got '<nil>'"),
+			err: errors.New("cannot get map value: unable to resolve a string index in map: could not resolve key for map/slice, expecting 'string' but got '<nil>'"),
 		},
 		{
 			name: "index map with int",
@@ -171,7 +172,7 @@ func Test_SetMapValue_Invalid(t *testing.T) {
 					G: getSetter,
 				},
 			},
-			err: errors.New("unable to resolve a string index in map: could not resolve key for map/slice, expecting 'string' but got '<nil>'"),
+			err: errors.New("cannot set map value: unable to resolve a string index in map: could not resolve key for map/slice, expecting 'string' but got '<nil>'"),
 		},
 		{
 			name: "index map with int",
@@ -311,3 +312,132 @@ func Test_SetMapValue_NilKey(t *testing.T) {
 	err := ctxutil.SetMapValue[any](context.Background(), nil, pcommon.NewMap(), nil, "bar")
 	assert.Error(t, err)
 }
+
+func Test_SetMap(t *testing.T) {
+	createMap := func() pcommon.Map {
+		m := pcommon.NewMap()
+		require.NoError(t, m.FromRaw(map[string]any{"foo": "bar"}))
+		return m
+	}
+	tests := []struct {
+		name string
+		val  any
+		err  error
+	}{
+		{
+			name: "invalid type",
+			val:  "invalid",
+			err:  errors.New("failed to convert type string into pcommon.Map"),
+		},
+		{
+			name: "raw map",
+			val:  map[string]any{"foo": "bar"},
+		},
+		{
+			name: "pcommon.Map",
+			val:  createMap(),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			m := pcommon.NewMap()
+			err := ctxutil.SetMap(m, tt.val)
+			if tt.err != nil {
+				require.Equal(t, tt.err, err)
+				return
+			}
+			assert.Equal(t, m, createMap())
+		})
+	}
+}
+
+func Test_GetMap(t *testing.T) {
+	createMap := func() pcommon.Map {
+		m := pcommon.NewMap()
+		require.NoError(t, m.FromRaw(map[string]any{"foo": "bar"}))
+		return m
+	}
+	tests := []struct {
+		name string
+		val  any
+		err  error
+	}{
+		{
+			name: "invalid type",
+			val:  "invalid",
+			err:  errors.New("failed to convert type string into pcommon.Map"),
+		},
+		{
+			name: "raw map",
+			val:  map[string]any{"foo": "bar"},
+		},
+		{
+			name: "pcommon.Map",
+			val:  createMap(),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			m, err := ctxutil.GetMap(tt.val)
+			if tt.err != nil {
+				require.Equal(t, tt.err, err)
+				return
+			}
+			assert.Equal(t, m, createMap())
+		})
+	}
+}
+
+func Test_GetMapKeyName(t *testing.T) {
+	getSetter := &ottl.StandardGetSetter[any]{
+		Getter: func(_ context.Context, _ any) (any, error) {
+			return nil, nil
+		},
+	}
+	tests := []struct {
+		name string
+		keys []ottl.Key[any]
+		err  error
+		key  string
+	}{
+		{
+			name: "first key not a string",
+			keys: []ottl.Key[any]{
+				&pathtest.Key[any]{
+					I: ottltest.Intp(0),
+					G: getSetter,
+				},
+			},
+			err: errors.New("unable to resolve a string index in map: could not resolve key for map/slice, expecting 'string' but got '<nil>'"),
+		},
+		{
+			name: "first key not initialized",
+			keys: []ottl.Key[any]{
+				&pathtest.Key[any]{},
+			},
+			err: errors.New("unable to resolve a string index in map: invalid key type"),
+		},
+		{
+			name: "valid",
+			keys: []ottl.Key[any]{
+				&pathtest.Key[any]{
+					S: ottltest.Strp("string"),
+				},
+			},
+			key: "string",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			resolvedKey, err := ctxutil.GetMapKeyName[any](context.Background(), nil, tt.keys[0])
+			if tt.err != nil {
+				assert.Equal(t, tt.err.Error(), err.Error())
+				return
+			}
+			assert.Equal(t, tt.key, *resolvedKey)
+		})
+	}
+}

pkg/ottl/contexts/internal/ctxutil/value.go

@@ -74,17 +74,10 @@ func getIndexableValue[K any](ctx context.Context, tCtx K, value pcommon.Value,
 	for index := 0; index < len(keys); index++ {
 		switch val.Type() {
 		case pcommon.ValueTypeMap:
-			s, err := keys[index].String(ctx, tCtx)
+			s, err := GetMapKeyName(ctx, tCtx, keys[index])
 			if err != nil {
 				return nil, err
 			}
-			if s == nil {
-				resString, err := FetchValueFromExpression[K, string](ctx, tCtx, keys[index])
-				if err != nil {
-					return nil, fmt.Errorf("unable to resolve a string index in map: %w", err)
-				}
-				s = resString
-			}
 			val, ok = val.Map().Get(*s)
 			if !ok {
 				return nil, nil
@@ -128,17 +121,10 @@ func SetIndexableValue[K any](ctx context.Context, tCtx K, currentValue pcommon.
 	for index := 0; index < len(keys); index++ {
 		switch currentValue.Type() {
 		case pcommon.ValueTypeMap:
-			s, err := keys[index].String(ctx, tCtx)
+			s, err := GetMapKeyName(ctx, tCtx, keys[index])
 			if err != nil {
 				return err
 			}
-			if s == nil {
-				resString, err := FetchValueFromExpression[K, string](ctx, tCtx, keys[index])
-				if err != nil {
-					return fmt.Errorf("unable to resolve a string index in map: %w", err)
-				}
-				s = resString
-			}
 			potentialValue, ok := currentValue.Map().Get(*s)
 			if !ok {
 				currentValue = currentValue.Map().PutEmpty(*s)