57 lines
1.0 KiB
Go
57 lines
1.0 KiB
Go
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package handler
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import (
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"errors"
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"io/fs"
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"net/http"
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"os"
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"path/filepath"
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"strings"
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)
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type FileHandler struct {
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Root string
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Default string
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http.FileSystem
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}
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func (f FileHandler) Open(name string) (http.File, error) {
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if strings.HasPrefix(name, "../") {
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return nil, errors.New("not permitted")
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}
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rPath := filepath.Join(f.Root, strings.TrimPrefix(name, "/"))
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if rPath == f.Root {
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if f.Default == "" {
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return nil, errors.New("not permit list dir")
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}
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rPath = filepath.Join(rPath, f.Default)
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}
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fInfo, _, err := FileExists(rPath)
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if err != nil {
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return nil, err
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}
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if fInfo.IsDir() {
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return nil, errors.New("not permit list dir")
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}
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if fInfo.Mode() == fs.ModeSymlink {
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return nil, errors.New("not permit follow symbol link")
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}
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return os.Open(rPath)
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}
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func FileExists(name string) (os.FileInfo, bool, error) {
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info, err := os.Stat(name)
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if err != nil {
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return nil, os.IsExist(err), err
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}
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return info, true, nil
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}
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func NewFileHandler(f FileHandler) http.Handler {
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return http.FileServer(f)
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}
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