ref: 837e084bbe53e9e2e6cd471d2a3daf273a874d92
dir: /hugofs/filter_fs.go/
// Copyright 2019 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package hugofs
import (
"fmt"
"io"
"os"
"path/filepath"
"sort"
"strings"
"syscall"
"time"
"github.com/gohugoio/hugo/hugofs/files"
"github.com/spf13/afero"
)
var (
_ afero.Fs = (*FilterFs)(nil)
_ afero.Lstater = (*FilterFs)(nil)
_ afero.File = (*filterDir)(nil)
)
func NewLanguageFs(langs map[string]int, fs afero.Fs) (afero.Fs, error) {
applyMeta := func(fs *FilterFs, name string, fis []os.FileInfo) {
for i, fi := range fis {
if fi.IsDir() {
filename := filepath.Join(name, fi.Name())
fis[i] = decorateFileInfo(fi, fs, fs.getOpener(filename), "", "", nil)
continue
}
meta := fi.(FileMetaInfo).Meta()
lang := meta.Lang()
fileLang, translationBaseName, translationBaseNameWithExt := langInfoFrom(langs, fi.Name())
weight := 0
if fileLang != "" {
weight = 1
if fileLang == lang {
// Give priority to myfile.sv.txt inside the sv filesystem.
weight++
}
lang = fileLang
}
fim := NewFileMetaInfo(fi, FileMeta{
metaKeyLang: lang,
metaKeyWeight: weight,
metaKeyOrdinal: langs[lang],
metaKeyTranslationBaseName: translationBaseName,
metaKeyTranslationBaseNameWithExt: translationBaseNameWithExt,
metaKeyClassifier: files.ClassifyContentFile(fi.Name(), meta.GetOpener()),
})
fis[i] = fim
}
}
all := func(fis []os.FileInfo) {
// Maps translation base name to a list of language codes.
translations := make(map[string][]string)
trackTranslation := func(meta FileMeta) {
name := meta.TranslationBaseNameWithExt()
translations[name] = append(translations[name], meta.Lang())
}
for _, fi := range fis {
if fi.IsDir() {
continue
}
meta := fi.(FileMetaInfo).Meta()
trackTranslation(meta)
}
for _, fi := range fis {
fim := fi.(FileMetaInfo)
langs := translations[fim.Meta().TranslationBaseNameWithExt()]
if len(langs) > 0 {
fim.Meta()["translations"] = sortAndremoveStringDuplicates(langs)
}
}
}
return &FilterFs{
fs: fs,
applyPerSource: applyMeta,
applyAll: all,
}, nil
}
func NewFilterFs(fs afero.Fs) (afero.Fs, error) {
applyMeta := func(fs *FilterFs, name string, fis []os.FileInfo) {
for i, fi := range fis {
if fi.IsDir() {
fis[i] = decorateFileInfo(fi, fs, fs.getOpener(fi.(FileMetaInfo).Meta().Filename()), "", "", nil)
}
}
}
ffs := &FilterFs{
fs: fs,
applyPerSource: applyMeta,
}
return ffs, nil
}
// FilterFs is an ordered composite filesystem.
type FilterFs struct {
fs afero.Fs
applyPerSource func(fs *FilterFs, name string, fis []os.FileInfo)
applyAll func(fis []os.FileInfo)
}
func (fs *FilterFs) Chmod(n string, m os.FileMode) error {
return syscall.EPERM
}
func (fs *FilterFs) Chtimes(n string, a, m time.Time) error {
return syscall.EPERM
}
func (fs *FilterFs) LstatIfPossible(name string) (os.FileInfo, bool, error) {
fi, b, err := lstatIfPossible(fs.fs, name)
if err != nil {
return nil, false, err
}
if fi.IsDir() {
return decorateFileInfo(fi, fs, fs.getOpener(name), "", "", nil), false, nil
}
parent := filepath.Dir(name)
fs.applyFilters(parent, -1, fi)
return fi, b, nil
}
func (fs *FilterFs) Mkdir(n string, p os.FileMode) error {
return syscall.EPERM
}
func (fs *FilterFs) MkdirAll(n string, p os.FileMode) error {
return syscall.EPERM
}
func (fs *FilterFs) Name() string {
return "WeightedFileSystem"
}
func (fs *FilterFs) Open(name string) (afero.File, error) {
f, err := fs.fs.Open(name)
if err != nil {
return nil, err
}
return &filterDir{
File: f,
ffs: fs,
}, nil
}
func (fs *FilterFs) OpenFile(name string, flag int, perm os.FileMode) (afero.File, error) {
return fs.fs.Open(name)
}
func (fs *FilterFs) ReadDir(name string) ([]os.FileInfo, error) {
panic("not implemented")
}
func (fs *FilterFs) Remove(n string) error {
return syscall.EPERM
}
func (fs *FilterFs) RemoveAll(p string) error {
return syscall.EPERM
}
func (fs *FilterFs) Rename(o, n string) error {
return syscall.EPERM
}
func (fs *FilterFs) Stat(name string) (os.FileInfo, error) {
fi, _, err := fs.LstatIfPossible(name)
return fi, err
}
func (fs *FilterFs) Create(n string) (afero.File, error) {
return nil, syscall.EPERM
}
func (fs *FilterFs) getOpener(name string) func() (afero.File, error) {
return func() (afero.File, error) {
return fs.Open(name)
}
}
func (fs *FilterFs) applyFilters(name string, count int, fis ...os.FileInfo) ([]os.FileInfo, error) {
if fs.applyPerSource != nil {
fs.applyPerSource(fs, name, fis)
}
seen := make(map[string]bool)
var duplicates []int
for i, dir := range fis {
if !dir.IsDir() {
continue
}
if seen[dir.Name()] {
duplicates = append(duplicates, i)
} else {
seen[dir.Name()] = true
}
}
// Remove duplicate directories, keep first.
if len(duplicates) > 0 {
for i := len(duplicates) - 1; i >= 0; i-- {
idx := duplicates[i]
fis = append(fis[:idx], fis[idx+1:]...)
}
}
if fs.applyAll != nil {
fs.applyAll(fis)
}
if count > 0 && len(fis) >= count {
return fis[:count], nil
}
return fis, nil
}
type filterDir struct {
afero.File
ffs *FilterFs
}
func (f *filterDir) Readdir(count int) ([]os.FileInfo, error) {
fis, err := f.File.Readdir(-1)
if err != nil {
return nil, err
}
return f.ffs.applyFilters(f.Name(), count, fis...)
}
func (f *filterDir) Readdirnames(count int) ([]string, error) {
dirsi, err := f.Readdir(count)
if err != nil {
return nil, err
}
dirs := make([]string, len(dirsi))
for i, d := range dirsi {
dirs[i] = d.Name()
}
return dirs, nil
}
// Try to extract the language from the given filename.
// Any valid language identificator in the name will win over the
// language set on the file system, e.g. "mypost.en.md".
func langInfoFrom(languages map[string]int, name string) (string, string, string) {
var lang string
baseName := filepath.Base(name)
ext := filepath.Ext(baseName)
translationBaseName := baseName
if ext != "" {
translationBaseName = strings.TrimSuffix(translationBaseName, ext)
}
fileLangExt := filepath.Ext(translationBaseName)
fileLang := strings.TrimPrefix(fileLangExt, ".")
if _, found := languages[fileLang]; found {
lang = fileLang
translationBaseName = strings.TrimSuffix(translationBaseName, fileLangExt)
}
translationBaseNameWithExt := translationBaseName
if ext != "" {
translationBaseNameWithExt += ext
}
return lang, translationBaseName, translationBaseNameWithExt
}
func printFs(fs afero.Fs, path string, w io.Writer) {
if fs == nil {
return
}
afero.Walk(fs, path, func(path string, info os.FileInfo, err error) error {
fmt.Println("p:::", path)
return nil
})
}
func sortAndremoveStringDuplicates(s []string) []string {
ss := sort.StringSlice(s)
ss.Sort()
i := 0
for j := 1; j < len(s); j++ {
if !ss.Less(i, j) {
continue
}
i++
s[i] = s[j]
}
return s[:i+1]
}