fine tune

Author: wxiaoguang

modules/assetfs/embed.go

@@ -21,7 +21,7 @@ import (
 
 type EmbeddedFile interface {
 	io.ReadSeeker
-	fs.File
+	fs.ReadDirFile
 	ReadDir(n int) ([]fs.DirEntry, error)
 }
 
@@ -50,6 +50,7 @@ type embeddedFileInfo struct {
 }
 
 func (fi *embeddedFileInfo) GetGzipContent() ([]byte, bool) {
+	// when generating the bindata, if the compressed data equals or is larger than the original data, we store the original data
 	if fi.DataLen == fi.OriginSize {
 		return nil, false
 	}
@@ -63,6 +64,7 @@ type EmbeddedFileBase struct {
 }
 
 func (f *EmbeddedFileBase) ReadDir(n int) ([]fs.DirEntry, error) {
+	// this method is used to satisfy the "func (f ioFile) ReadDir(...)" in httpfs
 	l, err := f.info.fs.ReadDir(f.info.fullName)
 	if err != nil {
 		return nil, err
@@ -83,10 +85,6 @@ type EmbeddedCompressedFile struct {
 	decompressorPos int64
 }
 
-func (f *EmbeddedCompressedFile) GzipBytes() []byte {
-	return f.info.data
-}
-
 type embeddedFS struct {
 	meta func() *EmbeddedMeta
 
@@ -336,20 +334,19 @@ func GenerateEmbedBindata(fsRootPath, outputFile string) error {
 				if err = gz.Close(); err != nil {
 					return err
 				}
-				outputBytes := util.Iif(len(compressed.Bytes()) < len(data), compressed.Bytes(), data)
 
+				// only use the compressed data if it is smaller than the original data
+				outputBytes := util.Iif(len(compressed.Bytes()) < len(data), compressed.Bytes(), data)
 				child := &embeddedFileInfo{
 					BaseName:   dirEntry.Name(),
 					OriginSize: int64(len(data)),
 					DataBegin:  outputOffset,
 					DataLen:    int64(len(outputBytes)),
 				}
-
 				if _, err = output.Write(outputBytes); err != nil {
 					return err
 				}
 				outputOffset += child.DataLen
-
 				parent.Children = append(parent.Children, child)
 			}
 		}

modules/assetfs/embed_test.go

@@ -27,21 +27,38 @@ func TestEmbed(t *testing.T) {
 	require.NoError(t, err)
 	efs := NewEmbeddedFS(data)
 
+	// test a non-existing file
 	_, err = fs.ReadFile(efs, "not exist")
 	assert.ErrorIs(t, err, fs.ErrNotExist)
 
+	// test a normal file (no compression)
 	content, err := fs.ReadFile(efs, "a.txt")
 	require.NoError(t, err)
 	assert.Equal(t, "a", string(content))
+	fi, err := fs.Stat(efs, "a.txt")
+	require.NoError(t, err)
+	_, ok := fi.(EmbeddedFileInfo).GetGzipContent()
+	assert.False(t, ok)
 
+	// test a compressed file
 	content, err = fs.ReadFile(efs, "foo/bar/b.txt")
 	require.NoError(t, err)
 	assert.Equal(t, bytes.Repeat([]byte("a"), 1000), content)
+	fi, err = fs.Stat(efs, "foo/bar/b.txt")
+	require.NoError(t, err)
+	gzipContent, ok := fi.(EmbeddedFileInfo).GetGzipContent()
+	assert.True(t, ok)
+	assert.Greater(t, len(gzipContent), 1)
+	assert.Less(t, len(gzipContent), 1000)
 
+	// test list root directory
 	entries, err := fs.ReadDir(efs, ".")
 	require.NoError(t, err)
 	assert.Len(t, entries, 2)
+	assert.Equal(t, "a.txt", entries[0].Name())
+	assert.False(t, entries[0].IsDir())
 
+	// test list subdirectory
 	entries, err = fs.ReadDir(efs, "foo")
 	require.NoError(t, err)
 	require.Len(t, entries, 2)
@@ -50,21 +67,23 @@ func TestEmbed(t *testing.T) {
 	assert.Equal(t, "c.txt", entries[1].Name())
 	assert.False(t, entries[1].IsDir())
 
-	entries, err = fs.ReadDir(efs, "foo/bar")
-	require.NoError(t, err)
-	require.Len(t, entries, 1)
-	assert.Equal(t, "b.txt", entries[0].Name())
-	assert.False(t, entries[0].IsDir())
-
+	// test httpfs
 	hfs := http.FS(efs)
 	hf, err := hfs.Open("foo/bar/b.txt")
 	require.NoError(t, err)
 	hi, err := hf.Stat()
 	require.NoError(t, err)
-	fi, ok := hi.(EmbeddedFileInfo)
+	fiEmbedded, ok := hi.(EmbeddedFileInfo)
 	require.True(t, ok)
-	gzipContent, ok := fi.GetGzipContent()
+	gzipContent, ok = fiEmbedded.GetGzipContent()
 	assert.True(t, ok)
 	assert.Greater(t, len(gzipContent), 1)
 	assert.Less(t, len(gzipContent), 1000)
+
+	// test httpfs directory listing
+	hf, err = hfs.Open("foo")
+	require.NoError(t, err)
+	dirs, err := hf.Readdir(1)
+	require.NoError(t, err)
+	assert.Len(t, dirs, 1)
 }