From 1ae1737c1c4be766771e6f1c8f84c176acf61174 Mon Sep 17 00:00:00 2001
From: Erik Unger <erik@erikunger.com>
Date: Fri, 17 May 2024 17:28:57 +0200
Subject: [PATCH] added RemoveFileProvider

---
 fileprovider.go | 71 ++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 55 insertions(+), 16 deletions(-)

diff --git a/fileprovider.go b/fileprovider.go
index 7833f84..3f4f6ff 100644
--- a/fileprovider.go
+++ b/fileprovider.go
@@ -26,12 +26,12 @@ type dirFileProvider struct {
 	dir fs.File
 }
 
-func (d dirFileProvider) HasFile(filename string) (bool, error) {
-	return d.dir.Join(filename).Exists(), nil
+func (p dirFileProvider) HasFile(filename string) (bool, error) {
+	return p.dir.Join(filename).Exists(), nil
 }
 
-func (d dirFileProvider) ListFiles(ctx context.Context) (filenames []string, err error) {
-	err = d.dir.ListDirContext(ctx, func(file fs.File) error {
+func (p dirFileProvider) ListFiles(ctx context.Context) (filenames []string, err error) {
+	err = p.dir.ListDirContext(ctx, func(file fs.File) error {
 		filenames = append(filenames, file.Name())
 		return nil
 	})
@@ -42,8 +42,8 @@ func (d dirFileProvider) ListFiles(ctx context.Context) (filenames []string, err
 	return filenames, nil
 }
 
-func (d dirFileProvider) ReadFile(ctx context.Context, filename string) ([]byte, error) {
-	return d.dir.Join(filename).ReadAllContext(ctx)
+func (p dirFileProvider) ReadFile(ctx context.Context, filename string) ([]byte, error) {
+	return p.dir.Join(filename).ReadAllContext(ctx)
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -52,7 +52,7 @@ func (d dirFileProvider) ReadFile(ctx context.Context, filename string) ([]byte,
 // ExtFileProvider returns a FileProvider that extends a base FileProvider
 // with additional files that will be returned before the files of the base FileProvider.
 func ExtFileProvider(base FileProvider, extFiles ...fs.FileReader) FileProvider {
-	return &extFileProvider{base, extFiles}
+	return extFileProvider{base, extFiles}
 }
 
 type extFileProvider struct {
@@ -60,21 +60,21 @@ type extFileProvider struct {
 	extFiles []fs.FileReader
 }
 
-func (e *extFileProvider) HasFile(filename string) (bool, error) {
-	for _, f := range e.extFiles {
+func (p extFileProvider) HasFile(filename string) (bool, error) {
+	for _, f := range p.extFiles {
 		if f.Name() == filename {
 			return true, nil
 		}
 	}
-	return e.base.HasFile(filename)
+	return p.base.HasFile(filename)
 }
 
-func (d extFileProvider) ListFiles(ctx context.Context) (filenames []string, err error) {
-	filenames, err = d.base.ListFiles(ctx)
+func (p extFileProvider) ListFiles(ctx context.Context) (filenames []string, err error) {
+	filenames, err = p.base.ListFiles(ctx)
 	if err != nil {
 		return nil, err
 	}
-	for _, f := range d.extFiles {
+	for _, f := range p.extFiles {
 		if !slices.Contains(filenames, f.Name()) {
 			filenames = append(filenames, f.Name())
 		}
@@ -83,13 +83,52 @@ func (d extFileProvider) ListFiles(ctx context.Context) (filenames []string, err
 	return filenames, nil
 }
 
-func (d extFileProvider) ReadFile(ctx context.Context, filename string) ([]byte, error) {
-	for _, f := range d.extFiles {
+func (p extFileProvider) ReadFile(ctx context.Context, filename string) ([]byte, error) {
+	for _, f := range p.extFiles {
 		if f.Name() == filename {
 			return f.ReadAllContext(ctx)
 		}
 	}
-	return d.base.ReadFile(ctx, filename)
+	return p.base.ReadFile(ctx, filename)
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// RemoveFileProvider
+
+// RemoveFileProvider returns a FileProvider that wraps a base FileProvider
+// and does not return files with the passed removeFilenames.
+func RemoveFileProvider(base FileProvider, removeFilenames ...string) FileProvider {
+	return &removeFileProvider{base, removeFilenames}
+}
+
+type removeFileProvider struct {
+	base   FileProvider
+	remove []string
+}
+
+func (p *removeFileProvider) HasFile(filename string) (bool, error) {
+	if slices.Contains(p.remove, filename) {
+		return false, nil
+	}
+	return p.base.HasFile(filename)
+}
+
+func (p removeFileProvider) ListFiles(ctx context.Context) (filenames []string, err error) {
+	filenames, err = p.base.ListFiles(ctx)
+	if err != nil {
+		return nil, err
+	}
+	filenames = slices.DeleteFunc(filenames, func(filename string) bool {
+		return slices.Contains(p.remove, filename)
+	})
+	return filenames, nil
+}
+
+func (p removeFileProvider) ReadFile(ctx context.Context, filename string) ([]byte, error) {
+	if slices.Contains(p.remove, filename) {
+		return nil, fs.NewErrPathDoesNotExist(filename)
+	}
+	return p.base.ReadFile(ctx, filename)
 }
 
 // func MemFileProvider(file fs.MemFile) FileProvider {