Merge pull request #30 from ryanleary/fix-transform-in-place

Add Transform and TransformInPlace

kazaam.go

@@ -167,11 +167,20 @@ func transformErrorType(err error) error {
 
 // Transform takes the *simplejson.Json `data`, transforms it according
 // to the loaded spec, and returns the modified *simplejson.Json object.
+func (k *Kazaam) Transform(data *simplejson.Json) (*simplejson.Json, error) {
+	d := simplejson.New()
+	d.SetPath(nil, data.Interface())
+	err := k.TransformInPlace(d)
+	return d, err
+}
+
+// TransformInPlace takes the *simplejson.Json `data`, transforms it according
+// to the loaded spec, and modifies the *simplejson.Json object.
 //
 // Note: this is a destructive operation: the transformation is done in place.
 // You must perform a deep copy of the data prior to calling Transform if
 // the original JSON object must be retained.
-func (k *Kazaam) Transform(data *simplejson.Json) (*simplejson.Json, error) {
+func (k *Kazaam) TransformInPlace(data *simplejson.Json) error {
 	var err error
 	for _, specObj := range k.specJSON {
 		//spec := specObj.Get("spec")
@@ -185,7 +194,7 @@ func (k *Kazaam) Transform(data *simplejson.Json) (*simplejson.Json, error) {
 				jsonValue.SetPath(nil, x)
 				intErr := k.getTransform(&specObj)(specObj.Config, jsonValue)
 				if intErr != nil {
-					return nil, transformErrorType(err)
+					return transformErrorType(err)
 				}
 				transformedDataList = append(transformedDataList, jsonValue.Interface())
 			}
@@ -196,7 +205,7 @@ func (k *Kazaam) Transform(data *simplejson.Json) (*simplejson.Json, error) {
 			err = transformErrorType(err)
 		}
 	}
-	return data, err
+	return err
 }
 
 // TransformJSONStringToString loads the JSON string `data`, transforms
@@ -207,11 +216,11 @@ func (k *Kazaam) TransformJSONStringToString(data string) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	outputJSON, err := k.Transform(d)
+	err = k.TransformInPlace(d)
 	if err != nil {
 		return "", err
 	}
-	jsonString, err := outputJSON.MarshalJSON()
+	jsonString, err := d.MarshalJSON()
 	if err != nil {
 		return "", err
 	}
@@ -229,5 +238,6 @@ func (k *Kazaam) TransformJSONString(data string) (*simplejson.Json, error) {
 	if err != nil {
 		return nil, err
 	}
-	return k.Transform(d)
+	k.TransformInPlace(d)
+	return d, nil
 }

kazaam_int_test.go

@@ -8,7 +8,7 @@ import (
 	"github.com/qntfy/kazaam/transform"
 )
 
-const testJSONInput = `{"rating": {"primary": {"value": 3}, "example": {"value": 3}}}`
+const testJSONInput = `{"rating":{"example":{"value":3},"primary":{"value":3}}}`
 
 func TestKazaamBadInput(t *testing.T) {
 	jsonOut := ``
@@ -242,18 +242,27 @@ func TestMissingRequiredField(t *testing.T) {
 	}
 }
 
-func TestNullRequiredField(t *testing.T) {
-	jsonIn := `{"meta": {"image_cache": null}, "doc": "example"}`
-	spec := `[
- 		{"operation": "shift", "spec": {"results": "meta.image_cache[0].results[*]"}, "require": true}
-	]`
-
-	kazaamTransform, _ := kazaam.NewKazaam(spec)
-	k, err := kazaamTransform.TransformJSONStringToString(jsonIn)
+func TestKazaamNoModify(t *testing.T) {
+	spec := `[{"operation": "shift","spec": {"Rating": "rating.primary.value","example.old": "rating.example"}}]`
+	msgOut := `{"Rating":3,"example":{"old":{"value":3}}}`
+	tf, _ := kazaam.NewKazaam(spec)
+	data, _ := simplejson.NewJson([]byte(testJSONInput))
+	k, _ := tf.Transform(data)
+
+	jsonOut, _ := k.MarshalJSON()
+	jsonOutStr := string(jsonOut)
+
+	if jsonOutStr != msgOut || jsonOutStr == testJSONInput {
+		t.Error("Unexpected transformation result")
+		t.Error("Actual:", jsonOutStr)
+		t.Error("Expected:", msgOut)
+	}
 
-	if err == nil {
-		t.Error("Should have generated error for null image_cache value")
-		t.Error(k)
+	b, _ := data.MarshalJSON()
+	if string(b) != testJSONInput {
+		t.Error("Unexpected modification")
+		t.Error("Actual:", string(b))
+		t.Error("Expected:", testJSONInput)
 	}
 }
 

transform/util.go

@@ -54,9 +54,10 @@ func getJSONPath(j *simplejson.Json, path string, pathRequired bool) (*simplejso
 				// get the array
 				var exists bool
 				jin, exists = jin.CheckGet(objKey)
-				if pathRequired && !exists {
-					return nil, RequireError("Path does not exist")
-					//return nil, &Error{ErrMsg: fmt.Sprintf("Path does not exist"), ErrType: RequireError}
+				if !exists {
+					if pathRequired {
+						return jin, RequireError("Path does not exist")
+					}
 				}
 				arrayLength := len(jin.MustArray())
 				// construct the remainder of the jsonPath