Adding the ability to exclude some files or file extensions in FileSystem Source

pkg/migration/filesystem.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"os"
+	gopath "path"
 	"path/filepath"
 
 	"github.com/pkg/errors"
@@ -20,9 +21,11 @@ var (
 
 // FileSystemSource is a source implementation to read resources from filesystem
 type FileSystemSource struct {
-	index int
-	items []UnstructuredWithMetadata
-	afero afero.Afero
+	index              int
+	items              []UnstructuredWithMetadata
+	afero              afero.Afero
+	excludedFiles      map[string]struct{}
+	excludedExtensions map[string]struct{}
 }
 
 // FileSystemSourceOption allows you to configure FileSystemSource
@@ -35,6 +38,20 @@ func FsWithFileSystem(f afero.Fs) FileSystemSourceOption {
 	}
 }
 
+// WithExcludedFiles configures the excludedFiles.
+func WithExcludedFiles(ef map[string]struct{}) FileSystemSourceOption {
+	return func(fs *FileSystemSource) {
+		fs.excludedFiles = ef
+	}
+}
+
+// WithExcludedExtensions configures the excludedExtensions.
+func WithExcludedExtensions(ee map[string]struct{}) FileSystemSourceOption {
+	return func(fs *FileSystemSource) {
+		fs.excludedExtensions = ee
+	}
+}
+
 // NewFileSystemSource returns a FileSystemSource
 func NewFileSystemSource(dir string, opts ...FileSystemSourceOption) (*FileSystemSource, error) {
 	fs := &FileSystemSource{
@@ -53,6 +70,10 @@ func NewFileSystemSource(dir string, opts ...FileSystemSourceOption) (*FileSyste
 			return nil
 		}
 
+		if isExcluded(path, fs.excludedFiles, fs.excludedExtensions) {
+			return nil
+		}
+
 		data, err := fs.afero.ReadFile(path)
 		if err != nil {
 			return errors.Wrap(err, "cannot read source file")
@@ -80,6 +101,16 @@ func NewFileSystemSource(dir string, opts ...FileSystemSourceOption) (*FileSyste
 	return fs, nil
 }
 
+func isExcluded(path string, excludedFiles, excludedExtensions map[string]struct{}) bool {
+	if _, ok := excludedFiles[path]; ok {
+		return true
+	}
+	if _, ok := excludedExtensions[gopath.Ext(path)]; ok {
+		return true
+	}
+	return false
+}
+
 // HasNext checks the next item
 func (fs *FileSystemSource) HasNext() (bool, error) {
 	return fs.index < len(fs.items), nil