code.vegaprotocol.io/vega@v0.79.0/libs/fs/fs.go (about)

     1  // Copyright (C) 2023 Gobalsky Labs Limited
     2  //
     3  // This program is free software: you can redistribute it and/or modify
     4  // it under the terms of the GNU Affero General Public License as
     5  // published by the Free Software Foundation, either version 3 of the
     6  // License, or (at your option) any later version.
     7  //
     8  // This program is distributed in the hope that it will be useful,
     9  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    10  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    11  // GNU Affero General Public License for more details.
    12  //
    13  // You should have received a copy of the GNU Affero General Public License
    14  // along with this program.  If not, see <http://www.gnu.org/licenses/>.
    15  
    16  package fs
    17  
    18  import (
    19  	"errors"
    20  	"fmt"
    21  	"io/fs"
    22  	"os"
    23  	"path/filepath"
    24  )
    25  
    26  var ErrIsADirectory = errors.New("is a directory")
    27  
    28  // EnsureDir will make sure a directory exists or is created at the given path.
    29  func EnsureDir(path string) error {
    30  	_, err := os.Stat(path)
    31  	if err != nil {
    32  		if os.IsNotExist(err) {
    33  			return os.MkdirAll(path, os.ModeDir|0o700)
    34  		}
    35  		return err
    36  	}
    37  	return nil
    38  }
    39  
    40  // PathExists returns whether a link exists at the given path.
    41  func PathExists(path string) (bool, error) {
    42  	_, err := os.Stat(path)
    43  	if err == nil {
    44  		return true, nil
    45  	}
    46  	if os.IsNotExist(err) {
    47  		return false, nil
    48  	}
    49  	return false, err
    50  }
    51  
    52  // FileExists similar to PathExists, but ensures the path is to a file, not a
    53  // directory.
    54  func FileExists(path string) (bool, error) {
    55  	fileInfo, err := os.Stat(path)
    56  	if err == nil {
    57  		if fileInfo.IsDir() {
    58  			return false, ErrIsADirectory
    59  		}
    60  		return true, nil
    61  	}
    62  	if os.IsNotExist(err) {
    63  		return false, nil
    64  	}
    65  	return false, err
    66  }
    67  
    68  func ReadFile(path string) ([]byte, error) {
    69  	dir, fileName := filepath.Split(path)
    70  	if len(dir) == 0 {
    71  		dir = "."
    72  	}
    73  
    74  	buf, err := fs.ReadFile(os.DirFS(dir), fileName)
    75  	if err != nil {
    76  		return nil, fmt.Errorf("couldn't read file: %w", err)
    77  	}
    78  
    79  	return buf, nil
    80  }
    81  
    82  func WriteFile(path string, content []byte) error {
    83  	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o600)
    84  	if err != nil {
    85  		return fmt.Errorf("couldn't create file: %w", err)
    86  	}
    87  	defer f.Close()
    88  
    89  	_, err = f.Write(content)
    90  	if err != nil {
    91  		return fmt.Errorf("couldn't write file: %w", err)
    92  	}
    93  
    94  	return nil
    95  }