assets: convert usage of go-bindata to Go embed (#6851)

Co-authored-by: Joe Chen <jc@unknwon.io>

1 files changed, 89 insertions, 0 deletions

diff --git a/templates/embed.go b/templates/embed.go
new file mode 100644
index 00000000..429f19ed
--- /dev/null
+++ b/templates/embed.go
@@ -0,0 +1,89 @@
+// Copyright 2020 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package templates
+
+import (
+	"bytes"
+	"embed"
+	"fmt"
+	"io"
+	"io/fs"
+	"io/ioutil"
+	"path"
+	"strings"
+
+	"gopkg.in/macaron.v1"
+
+	"gogs.io/gogs/internal/osutil"
+)
+
+//go:embed *.tmpl **/*
+var files embed.FS
+
+// fileSystem implements the macaron.TemplateFileSystem interface.
+type fileSystem struct {
+	files []macaron.TemplateFile
+}
+
+func (fs *fileSystem) ListFiles() []macaron.TemplateFile {
+	return fs.files
+}
+
+func (fs *fileSystem) Get(name string) (io.Reader, error) {
+	for i := range fs.files {
+		if fs.files[i].Name()+fs.files[i].Ext() == name {
+			return bytes.NewReader(fs.files[i].Data()), nil
+		}
+	}
+	return nil, fmt.Errorf("file %q not found", name)
+}
+
+func mustNames(fsys fs.FS) []string {
+	var names []string
+	walkDirFunc := func(path string, d fs.DirEntry, err error) error {
+		if !d.IsDir() {
+			names = append(names, path)
+		}
+		return nil
+	}
+	if err := fs.WalkDir(fsys, ".", walkDirFunc); err != nil {
+		panic("assetNames failure: " + err.Error())
+	}
+	return names
+}
+
+// NewTemplateFileSystem returns a macaron.TemplateFileSystem instance for embedded assets.
+// The argument "dir" can be used to serve subset of embedded assets. Template file
+// found under the "customDir" on disk has higher precedence over embedded assets.
+func NewTemplateFileSystem(dir, customDir string) macaron.TemplateFileSystem {
+	if dir != "" && !strings.HasSuffix(dir, "/") {
+		dir += "/"
+	}
+
+	var err error
+	var tmplFiles []macaron.TemplateFile
+	names := mustNames(files)
+	for _, name := range names {
+		if !strings.HasPrefix(name, dir) {
+			continue
+		}
+		// Check if corresponding custom file exists
+		var data []byte
+		fpath := path.Join(customDir, name)
+		if osutil.IsFile(fpath) {
+			data, err = ioutil.ReadFile(fpath)
+		} else {
+			data, err = files.ReadFile(name)
+		}
+		if err != nil {
+			panic(err)
+		}
+		name = strings.TrimPrefix(name, dir)
+		ext := path.Ext(name)
+		name = strings.TrimSuffix(name, ext)
+		tmplFiles = append(tmplFiles, macaron.NewTplFile(name, data, ext))
+	}
+	return &fileSystem{files: tmplFiles}
+}