Validate attribute names are correct when parsing JSON/YAML (#74)

glide.yaml

@@ -24,3 +24,5 @@ import:
     ref:     c72df929b80ef4930aaa75d5e486887ff2f3e06a
   - package: gopkg.in/yaml.v2
     ref:     f7716cbe52baa25d2e9b0d0da546fcf909fc16b4
+  - package: github.com/oleiade/reflections
+    ref:     632977f98cd34d217c4b57d0840ec188b3d3dcaf

resource/resource.go

@@ -4,8 +4,10 @@ import (
 	"fmt"
 	"path/filepath"
 	"strconv"
+	"strings"
 
 	"github.com/aelsabbahy/goss/system"
+	"github.com/oleiade/reflections"
 )
 
 type Resource interface {
@@ -43,3 +45,15 @@ func deprecateAtoI(depr interface{}, desc string) interface{} {
 	}
 	return float64(i)
 }
+
+func validAttrs(i interface{}, t string) (map[string]bool, error) {
+	validAttrs := make(map[string]bool)
+	tags, err := reflections.Tags(i, t)
+	if err != nil {
+		return nil, err
+	}
+	for _, v := range tags {
+		validAttrs[strings.Split(v, ",")[0]] = true
+	}
+	return validAttrs, nil
+}