Include json files for fn source

kyaml/kio/pkgio_reader.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"sigs.k8s.io/kustomize/kyaml/errors"
 	"sigs.k8s.io/kustomize/kyaml/kio/kioutil"
@@ -162,10 +163,18 @@ type LocalPackageReader struct {
 
 	// SetAnnotations are annotations to set on the Resources as they are read.
 	SetAnnotations map[string]string `yaml:"setAnnotations,omitempty"`
+
+	// IncludeJSON indicates if the json resources files must be included during read
+	IncludeJSON bool
 }
 
 var _ Reader = LocalPackageReader{}
 
+const (
+	JSONFilePattern = "*.json"
+	JSONSuffix      = ".json"
+)
+
 var DefaultMatch = []string{"*.yaml", "*.yml"}
 
 // Read reads the Resources.
@@ -178,6 +187,9 @@ func (r LocalPackageReader) Read() ([]*yaml.RNode, error) {
 	r.PackagePath = filepath.ToSlash(r.PackagePath)
 	if len(r.MatchFilesGlob) == 0 {
 		r.MatchFilesGlob = DefaultMatch
+		if r.IncludeJSON {
+			r.MatchFilesGlob = append(r.MatchFilesGlob, JSONFilePattern)
+		}
 	}
 
 	var operand ResourceNodeSlice
@@ -243,6 +255,7 @@ func (r *LocalPackageReader) readFile(path string, _ os.FileInfo) ([]*yaml.RNode
 		Reader:                f,
 		OmitReaderAnnotations: r.OmitReaderAnnotations,
 		SetAnnotations:        r.SetAnnotations,
+		JSON:                  strings.HasSuffix(path, JSONSuffix),
 	}
 	return rr.Read()
 }