Split marshal package from yqlib, implement interfaces

pkg/marshal/json_converter.go

@@ -0,0 +1,54 @@
+package marshal
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+
+	yaml "github.com/mikefarah/yaml/v2"
+)
+
+type JsonConverter interface {
+	JsonToString(context interface{}) (string, error)
+}
+
+type jsonConverter struct {}
+
+func NewJsonConverter() JsonConverter {
+	return &jsonConverter{}
+}
+
+func (j *jsonConverter) JsonToString(context interface{}) (string, error) {
+	out, err := json.Marshal(j.toJSON(context))
+	if err != nil {
+		return "", fmt.Errorf("error printing yaml as json: %v", err)
+	}
+	return string(out), nil
+}
+
+func (j *jsonConverter) toJSON(context interface{}) interface{} {
+	switch context := context.(type) {
+	case []interface{}:
+		oldArray := context
+		newArray := make([]interface{}, len(oldArray))
+		for index, value := range oldArray {
+			newArray[index] = j.toJSON(value)
+		}
+		return newArray
+	case yaml.MapSlice:
+		oldMap := context
+		newMap := make(map[string]interface{})
+		for _, entry := range oldMap {
+			if str, ok := entry.Key.(string); ok {
+				newMap[str] = j.toJSON(entry.Value)
+			} else if i, ok := entry.Key.(int); ok {
+				newMap[strconv.Itoa(i)] = j.toJSON(entry.Value)
+			} else if b, ok := entry.Key.(bool); ok {
+				newMap[strconv.FormatBool(b)] = j.toJSON(entry.Value)
+			}
+		}
+		return newMap
+	default:
+		return context
+	}
+}

pkg/marshal/json_converter_test.go

@@ -0,0 +1,47 @@
+package marshal
+
+import (
+	"testing"
+	"github.com/mikefarah/yq/test"
+)
+
+func TestJsonToString(t *testing.T) {
+	var data = test.ParseData(`
+---
+b:
+  c: 2
+`)
+	got, _ := NewJsonConverter().JsonToString(data)
+	test.AssertResult(t, "{\"b\":{\"c\":2}}", got)
+}
+
+func TestJsonToString_withIntKey(t *testing.T) {
+	var data = test.ParseData(`
+---
+b:
+  2: c
+`)
+	got, _ := NewJsonConverter().JsonToString(data)
+	test.AssertResult(t, `{"b":{"2":"c"}}`, got)
+}
+
+func TestJsonToString_withBoolKey(t *testing.T) {
+	var data = test.ParseData(`
+---
+b:
+  false: c
+`)
+	got, _ := NewJsonConverter().JsonToString(data)
+	test.AssertResult(t, `{"b":{"false":"c"}}`, got)
+}
+
+func TestJsonToString_withArray(t *testing.T) {
+	var data = test.ParseData(`
+---
+b:
+  - item: one
+  - item: two
+`)
+	got, _ := NewJsonConverter().JsonToString(data)
+	test.AssertResult(t, "{\"b\":[{\"item\":\"one\"},{\"item\":\"two\"}]}", got)
+}

pkg/marshal/yaml_converter.go

@@ -0,0 +1,42 @@
+package marshal
+
+import (
+	yaml "github.com/mikefarah/yaml/v2"
+	errors "github.com/pkg/errors"
+	"strings"
+)
+
+type YamlConverter interface {
+	YamlToString(context interface{}, trimOutput bool) (string, error)
+}
+
+type yamlConverter struct {}
+
+func NewYamlConverter() YamlConverter {
+	return &yamlConverter{}
+}
+
+func (y *yamlConverter) YamlToString(context interface{}, trimOutput bool) (string, error) {
+	switch context := context.(type) {
+	case string:
+		return context, nil
+	default:
+		return y.marshalContext(context, trimOutput)
+	}
+}
+
+func (y *yamlConverter) marshalContext(context interface{}, trimOutput bool) (string, error) {
+	out, err := yaml.Marshal(context)
+
+	if err != nil {
+		return "", errors.Wrap(err, "error printing yaml")
+	}
+
+	outStr := string(out)
+	// trim the trailing new line as it's easier for a script to add
+	// it in if required than to remove it
+	if trimOutput {
+		return strings.Trim(outStr, "\n "), nil
+	}
+	return outStr, nil
+}