Workaround for Windows Containers

notebook/services/contents/filemanager.py

@@ -9,6 +9,7 @@
 import os
 import shutil
 import stat
+import sys
 import warnings
 import mimetypes
 import nbformat
@@ -18,6 +19,7 @@
 from .filecheckpoints import FileCheckpoints
 from .fileio import FileManagerMixin
 from .manager import ContentsManager
+from ...utils import exists
 
 from ipython_genutils.importstring import import_item
 from traitlets import Any, Unicode, Bool, TraitError, observe, default, validate
@@ -220,12 +222,12 @@ def exists(self, path):
         """
         path = path.strip('/')
         os_path = self._get_os_path(path=path)
-        return os.path.exists(os_path)
+        return exists(os_path)
 
     def _base_model(self, path):
         """Build the common base of a contents model"""
         os_path = self._get_os_path(path)
-        info = os.stat(os_path)
+        info = os.lstat(os_path)
         last_modified = tz.utcfromtimestamp(info.st_mtime)
         created = tz.utcfromtimestamp(info.st_ctime)
         # Create the base model.
@@ -275,7 +277,7 @@ def _dir_model(self, path, content=True):
                     continue
 
                 try:
-                    st = os.stat(os_path)
+                    st = os.lstat(os_path)
                 except OSError as e:
                     # skip over broken symlinks in listing
                     if e.errno == errno.ENOENT:
@@ -284,7 +286,9 @@ def _dir_model(self, path, content=True):
                         self.log.warning("Error stat-ing %s: %s", os_path, e)
                     continue
 
-                if not stat.S_ISREG(st.st_mode) and not stat.S_ISDIR(st.st_mode):
+                if (not stat.S_ISLNK(st.st_mode)
+                        and not stat.S_ISREG(st.st_mode)
+                        and not stat.S_ISDIR(st.st_mode)):
                     self.log.debug("%s not a regular file", os_path)
                     continue
 

notebook/services/contents/tests/test_manager.py

@@ -108,7 +108,7 @@ def test_checkpoint_subdir(self):
         self.assertEqual(cp_dir, os.path.join(root, cpm.checkpoint_dir, cp_name))
         self.assertEqual(cp_subdir, os.path.join(root, subd, cpm.checkpoint_dir, cp_name))
 
-    @dec.skip_win32
+    @dec.skipif(sys.platform == 'win32' and sys.version_info[0] < 3)
     def test_bad_symlink(self):
         with TemporaryDirectory() as td:
             cm = FileContentsManager(root_dir=td)
@@ -120,9 +120,16 @@ def test_bad_symlink(self):
             # create a broken symlink
             self.symlink(cm, "target", '%s/%s' % (path, 'bad symlink'))
             model = cm.get(path)
-            self.assertEqual(model['content'], [file_model])
 
-    @dec.skip_win32
+            contents = {
+                content['name']: content for content in model['content']
+            }
+            self.assertTrue('untitled.txt' in contents)
+            self.assertEqual(contents['untitled.txt'], file_model)
+            # broken symlinks should still be shown in the contents manager
+            self.assertTrue('bad symlink' in contents)
+
+    @dec.skipif(sys.platform == 'win32' and sys.version_info[0] < 3)
     def test_good_symlink(self):
         with TemporaryDirectory() as td:
             cm = FileContentsManager(root_dir=td)
@@ -224,7 +231,7 @@ def check_populated_dir_files(self, api_path):
                 self.assertEqual(entry['name'], "nb.ipynb")
                 complete_path = "/".join([api_path, "nb.ipynb"])
                 self.assertEqual(entry["path"], complete_path)
-    
+
     def setUp(self):
         self._temp_dir = TemporaryDirectory()
         self.td = self._temp_dir.name

notebook/services/kernels/kernelmanager.py

@@ -17,7 +17,7 @@
 from jupyter_client.multikernelmanager import MultiKernelManager
 from traitlets import Bool, Dict, List, Unicode, TraitError, Integer, default, validate
 
-from notebook.utils import to_os_path
+from notebook.utils import to_os_path, exists
 from notebook._tz import utcnow, isoformat
 from ipython_genutils.py3compat import getcwd
 
@@ -55,7 +55,7 @@ def _update_root_dir(self, proposal):
         if not os.path.isabs(value):
             # If we receive a non-absolute path, make it absolute.
             value = os.path.abspath(value)
-        if not os.path.exists(value) or not os.path.isdir(value):
+        if not exists(value) or not os.path.isdir(value):
             raise TraitError("kernel root dir %r is not a directory" % value)
         return value
 

notebook/utils.py

@@ -25,6 +25,17 @@
 UF_HIDDEN = getattr(stat, 'UF_HIDDEN', 32768)
 
 
+def exists(path):
+    """Replacement for `os.path.exists` which works for host mapped volumes
+    on Windows containers
+    """
+    try:
+        os.lstat(path)
+    except OSError:
+        return False
+    return True
+
+
 def url_path_join(*pieces):
     """Join components of url into a relative url
 
@@ -58,26 +69,25 @@ def url2path(url):
     pieces = [ unquote(p) for p in url.split('/') ]
     path = os.path.join(*pieces)
     return path
-    
+
 def url_escape(path):
     """Escape special characters in a URL path
-    
+
     Turns '/foo bar/' into '/foo%20bar/'
     """
     parts = py3compat.unicode_to_str(path, encoding='utf8').split('/')
     return u'/'.join([quote(p) for p in parts])
 
 def url_unescape(path):
     """Unescape special characters in a URL path
-    
+
     Turns '/foo%20bar/' into '/foo bar/'
     """
     return u'/'.join([
         py3compat.str_to_unicode(unquote(p), encoding='utf8')
         for p in py3compat.unicode_to_str(path, encoding='utf8').split('/')
     ])
 
-_win32_FILE_ATTRIBUTE_HIDDEN = 0x02
 
 def is_file_hidden_win(abs_path, stat_res=None):
     """Is a file hidden?
@@ -98,22 +108,15 @@ def is_file_hidden_win(abs_path, stat_res=None):
     if os.path.basename(abs_path).startswith('.'):
         return True
 
-    # check that dirs can be listed
-    if os.path.isdir(abs_path):
-        # can't trust os.access on Windows because it seems to always return True
-        try:
-            os.stat(abs_path)
-        except OSError:
-            # stat may fail on Windows junctions or non-user-readable dirs
-            return True
-
+    win32_FILE_ATTRIBUTE_HIDDEN = 0x02
     try:
         attrs = ctypes.windll.kernel32.GetFileAttributesW(
-            py3compat.cast_unicode(abs_path))
+            py3compat.cast_unicode(abs_path)
+        )
     except AttributeError:
         pass
     else:
-        if attrs > 0 and attrs & _win32_FILE_ATTRIBUTE_HIDDEN:
+        if attrs > 0 and attrs & win32_FILE_ATTRIBUTE_HIDDEN:
             return True
 
     return False
@@ -164,12 +167,12 @@ def is_file_hidden_posix(abs_path, stat_res=None):
 
 def is_hidden(abs_path, abs_root=''):
     """Is a file hidden or contained in a hidden directory?
-    
+
     This will start with the rightmost path element and work backwards to the
     given root to see if a path is hidden or in a hidden directory. Hidden is
-    determined by either name starting with '.' or the UF_HIDDEN flag as 
+    determined by either name starting with '.' or the UF_HIDDEN flag as
     reported by stat.
-    
+
     Parameters
     ----------
     abs_path : unicode
@@ -191,12 +194,12 @@ def is_hidden(abs_path, abs_root=''):
     # is_file_hidden() already checked the file, so start from its parent dir
     path = os.path.dirname(abs_path)
     while path and path.startswith(abs_root) and path != abs_root:
-        if not os.path.exists(path):
+        if not exists(path):
             path = os.path.dirname(path)
             continue
         try:
             # may fail on Windows junctions
-            st = os.stat(path)
+            st = os.lstat(path)
         except OSError:
             return True
         if getattr(st, 'st_flags', 0) & UF_HIDDEN:
@@ -244,7 +247,7 @@ def to_os_path(path, root=''):
 
 def to_api_path(os_path, root=''):
     """Convert a filesystem path to an API path
-    
+
     If given, root will be removed from the path.
     root must be a filesystem path already.
     """