github.com/powerman/golang-tools@v0.1.11-0.20220410185822-5ad214d8d803/godoc/vfs/vfs.go (about)

     1  // Copyright 2013 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Package vfs defines types for abstract file system access and provides an
     6  // implementation accessing the file system of the underlying OS.
     7  package vfs // import "github.com/powerman/golang-tools/godoc/vfs"
     8  
     9  import (
    10  	"io"
    11  	"io/ioutil"
    12  	"os"
    13  )
    14  
    15  // RootType indicates the type of files contained within a directory.
    16  //
    17  // It is used to indicate whether a directory is the root
    18  // of a GOROOT, a GOPATH, or neither.
    19  // An empty string represents the case when a directory is neither.
    20  type RootType string
    21  
    22  const (
    23  	RootTypeGoRoot RootType = "GOROOT"
    24  	RootTypeGoPath RootType = "GOPATH"
    25  )
    26  
    27  // The FileSystem interface specifies the methods godoc is using
    28  // to access the file system for which it serves documentation.
    29  type FileSystem interface {
    30  	Opener
    31  	Lstat(path string) (os.FileInfo, error)
    32  	Stat(path string) (os.FileInfo, error)
    33  	ReadDir(path string) ([]os.FileInfo, error)
    34  	RootType(path string) RootType
    35  	String() string
    36  }
    37  
    38  // Opener is a minimal virtual filesystem that can only open regular files.
    39  type Opener interface {
    40  	Open(name string) (ReadSeekCloser, error)
    41  }
    42  
    43  // A ReadSeekCloser can Read, Seek, and Close.
    44  type ReadSeekCloser interface {
    45  	io.Reader
    46  	io.Seeker
    47  	io.Closer
    48  }
    49  
    50  // ReadFile reads the file named by path from fs and returns the contents.
    51  func ReadFile(fs Opener, path string) ([]byte, error) {
    52  	rc, err := fs.Open(path)
    53  	if err != nil {
    54  		return nil, err
    55  	}
    56  	defer rc.Close()
    57  	return ioutil.ReadAll(rc)
    58  }