add ability to update yaml path while preserving comments

pkg/utils/yaml_utils/yaml_utils.go

@@ -0,0 +1,54 @@
+package yaml_utils
+
+import (
+	"fmt"
+
+	"gopkg.in/yaml.v3"
+)
+
+// takes a yaml document in bytes, a path to a key, and a value to set. The value must be a scalar.
+func UpdateYaml(yamlBytes []byte, path []string, value string) ([]byte, error) {
+	// Parse the YAML file.
+	var node yaml.Node
+	err := yaml.Unmarshal(yamlBytes, &node)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse YAML: %w", err)
+	}
+
+	body := node.Content[0]
+
+	updateYamlNode(body, path, value)
+
+	// Convert the updated YAML node back to YAML bytes.
+	updatedYAMLBytes, err := yaml.Marshal(body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to convert YAML node to bytes: %w", err)
+	}
+
+	return updatedYAMLBytes, nil
+}
+
+// Recursive function to update the YAML node.
+func updateYamlNode(node *yaml.Node, path []string, value string) {
+	if len(path) == 0 {
+		node.Value = value
+		return
+	}
+
+	key := path[0]
+	for i := 0; i < len(node.Content)-1; i += 2 {
+		if node.Content[i].Value == key {
+			updateYamlNode(node.Content[i+1], path[1:], value)
+			return
+		}
+	}
+
+	// if the key doesn't exist, we'll add it
+	node.Content = append(node.Content, &yaml.Node{
+		Kind:  yaml.ScalarNode,
+		Value: key,
+	}, &yaml.Node{
+		Kind:  yaml.ScalarNode,
+		Value: value,
+	})
+}