chrome/common/extensions/docs/server2/local_file_system.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import os
   6 import sys
   7
   8 from docs_server_utils import StringIdentity
   9 from file_system import FileSystem, FileNotFoundError, StatInfo
  10 from future import Future
  11 from path_util import AssertIsDirectory, AssertIsValid
  12 from test_util import ChromiumPath
  13
  14
  15 def _ConvertToFilepath(path):
  16   return path.replace('/', os.sep)
  17
  18
  19 def _ConvertFromFilepath(path):
  20   return path.replace(os.sep, '/')
  21
  22
  23 def _ReadFile(filename):
  24   try:
  25     with open(filename, 'rb') as f:
  26       return f.read()
  27   except IOError as e:
  28     raise FileNotFoundError('Read failed for %s: %s' % (filename, e))
  29
  30
  31 def _ListDir(dir_name):
  32   all_files = []
  33   try:
  34     files = os.listdir(dir_name)
  35   except OSError as e:
  36     raise FileNotFoundError('os.listdir failed for %s: %s' % (dir_name, e))
  37   for os_path in files:
  38     posix_path = _ConvertFromFilepath(os_path)
  39     if os_path.startswith('.'):
  40       continue
  41     if os.path.isdir(os.path.join(dir_name, os_path)):
  42       all_files.append(posix_path + '/')
  43     else:
  44       all_files.append(posix_path)
  45   return all_files
  46
  47
  48 def _CreateStatInfo(path):
  49   try:
  50     path_mtime = os.stat(path).st_mtime
  51     if os.path.isdir(path):
  52       child_versions = dict((_ConvertFromFilepath(filename),
  53                              os.stat(os.path.join(path, filename)).st_mtime)
  54           for filename in os.listdir(path))
  55       # This file system stat mimics subversion, where the stat of directories
  56       # is max(file stats). That means we need to recursively check the whole
  57       # file system tree :\ so approximate that by just checking this dir.
  58       version = max([path_mtime] + child_versions.values())
  59     else:
  60       child_versions = None
  61       version = path_mtime
  62     return StatInfo(version, child_versions)
  63   except OSError as e:
  64     raise FileNotFoundError('os.stat failed for %s: %s' % (path, e))
  65
  66
  67 class LocalFileSystem(FileSystem):
  68   '''FileSystem implementation which fetches resources from the local
  69   filesystem.
  70   '''
  71   def __init__(self, base_path):
  72     # Enforce POSIX path, so path validity checks pass for Windows.
  73     base_path = base_path.replace(os.sep, '/')
  74     AssertIsDirectory(base_path)
  75     self._base_path = _ConvertToFilepath(base_path)
  76
  77   @staticmethod
  78   def Create(*path):
  79     return LocalFileSystem(ChromiumPath(*path))
  80
  81   def Read(self, paths, skip_not_found=False):
  82     def resolve():
  83       result = {}
  84       for path in paths:
  85         AssertIsValid(path)
  86         full_path = os.path.join(self._base_path,
  87                                  _ConvertToFilepath(path).lstrip(os.sep))
  88         if path == '' or path.endswith('/'):
  89           result[path] = _ListDir(full_path)
  90         else:
  91           try:
  92             result[path] = _ReadFile(full_path)
  93           except FileNotFoundError:
  94             if skip_not_found:
  95               continue
  96             return Future(exc_info=sys.exc_info())
  97       return result
  98     return Future(callback=resolve)
  99
 100   def Refresh(self):
 101     return Future(value=())
 102
 103   def Stat(self, path):
 104     AssertIsValid(path)
 105     full_path = os.path.join(self._base_path,
 106                              _ConvertToFilepath(path).lstrip(os.sep))
 107     return _CreateStatInfo(full_path)
 108
 109   def GetIdentity(self):
 110     return '@'.join((self.__class__.__name__, StringIdentity(self._base_path)))
 111
 112   def __repr__(self):
 113     return 'LocalFileSystem(%s)' % self._base_path