"""A base class for contents managers.""" # Copyright (c) IPython Development Team. # Distributed under the terms of the Modified BSD License. from fnmatch import fnmatch import itertools import json import os import re from tornado.web import HTTPError from .checkpoints import Checkpoints from IPython.config.configurable import LoggingConfigurable from IPython.nbformat import sign, validate, ValidationError from IPython.nbformat.v4 import new_notebook from IPython.utils.importstring import import_item from IPython.utils.traitlets import ( Any, Dict, Instance, List, TraitError, Type, Unicode, ) from IPython.utils.py3compat import string_types copy_pat = re.compile(r'\-Copy\d*\.') class ContentsManager(LoggingConfigurable): """Base class for serving files and directories. This serves any text or binary file, as well as directories, with special handling for JSON notebook documents. Most APIs take a path argument, which is always an API-style unicode path, and always refers to a directory. - unicode, not url-escaped - '/'-separated - leading and trailing '/' will be stripped - if unspecified, path defaults to '', indicating the root path. """ notary = Instance(sign.NotebookNotary) def _notary_default(self): return sign.NotebookNotary(parent=self) hide_globs = List(Unicode, [ u'__pycache__', '*.pyc', '*.pyo', '.DS_Store', '*.so', '*.dylib', '*~', ], config=True, help=""" Glob patterns to hide in file and directory listings. """) untitled_notebook = Unicode("Untitled", config=True, help="The base name used when creating untitled notebooks." ) untitled_file = Unicode("untitled", config=True, help="The base name used when creating untitled files." ) untitled_directory = Unicode("Untitled Folder", config=True, help="The base name used when creating untitled directories." ) pre_save_hook = Any(None, config=True, help="""Python callable or importstring thereof To be called on a contents model prior to save. This can be used to process the structure, such as removing notebook outputs or other side effects that should not be saved. It will be called as (all arguments passed by keyword): hook(path=path, model=model, contents_manager=self) model: the model to be saved. Includes file contents. modifying this dict will affect the file that is stored. path: the API path of the save destination contents_manager: this ContentsManager instance """ ) def _pre_save_hook_changed(self, name, old, new): if new and isinstance(new, string_types): self.pre_save_hook = import_item(self.pre_save_hook) elif new: if not callable(new): raise TraitError("pre_save_hook must be callable") def run_pre_save_hook(self, model, path, **kwargs): """Run the pre-save hook if defined, and log errors""" if self.pre_save_hook: try: self.log.debug("Running pre-save hook on %s", path) self.pre_save_hook(model=model, path=path, contents_manager=self, **kwargs) except Exception: self.log.error("Pre-save hook failed on %s", path, exc_info=True) checkpoints_class = Type(Checkpoints, config=True) checkpoints = Instance(Checkpoints, config=True) checkpoints_kwargs = Dict(allow_none=False, config=True) def _checkpoints_default(self): return self.checkpoints_class(**self.checkpoints_kwargs) def _checkpoints_kwargs_default(self): return dict( parent=self, log=self.log, ) # ContentsManager API part 1: methods that must be # implemented in subclasses. def dir_exists(self, path): """Does the API-style path (directory) actually exist? Like os.path.isdir Override this method in subclasses. Parameters ---------- path : string The path to check Returns ------- exists : bool Whether the path does indeed exist. """ raise NotImplementedError def is_hidden(self, path): """Does the API style path correspond to a hidden directory or file? Parameters ---------- path : string The path to check. This is an API path (`/` separated, relative to root dir). Returns ------- hidden : bool Whether the path is hidden. """ raise NotImplementedError def file_exists(self, path=''): """Does a file exist at the given path? Like os.path.isfile Override this method in subclasses. Parameters ---------- name : string The name of the file you are checking. path : string The relative path to the file's directory (with '/' as separator) Returns ------- exists : bool Whether the file exists. """ raise NotImplementedError('must be implemented in a subclass') def exists(self, path): """Does a file or directory exist at the given path? Like os.path.exists Parameters ---------- path : string The relative path to the file's directory (with '/' as separator) Returns ------- exists : bool Whether the target exists. """ return self.file_exists(path) or self.dir_exists(path) def get(self, path, content=True, type=None, format=None): """Get the model of a file or directory with or without content.""" raise NotImplementedError('must be implemented in a subclass') def save(self, model, path): """Save the file or directory and return the model with no content. Save implementations should call self.run_pre_save_hook(model=model, path=path) prior to writing any data. """ raise NotImplementedError('must be implemented in a subclass') def delete_file(self, path): """Delete file or directory by path.""" raise NotImplementedError('must be implemented in a subclass') def rename_file(self, old_path, new_path): """Rename a file.""" raise NotImplementedError('must be implemented in a subclass') # ContentsManager API part 2: methods that have useable default # implementations, but can be overridden in subclasses. def delete(self, path): """Delete a file/directory and any associated checkpoints.""" self.delete_file(path) self.checkpoints.delete_all_checkpoints(path) def rename(self, old_path, new_path): """Rename a file and any checkpoints associated with that file.""" self.rename_file(old_path, new_path) self.checkpoints.rename_all_checkpoints(old_path, new_path) def update(self, model, path): """Update the file's path For use in PATCH requests, to enable renaming a file without re-uploading its contents. Only used for renaming at the moment. """ path = path.strip('/') new_path = model.get('path', path).strip('/') if path != new_path: self.rename(path, new_path) model = self.get(new_path, content=False) return model def info_string(self): return "Serving contents" def get_kernel_path(self, path, model=None): """Return the API path for the kernel KernelManagers can turn this value into a filesystem path, or ignore it altogether. The default value here will start kernels in the directory of the notebook server. FileContentsManager overrides this to use the directory containing the notebook. """ return '' def increment_filename(self, filename, path='', insert=''): """Increment a filename until it is unique. Parameters ---------- filename : unicode The name of a file, including extension path : unicode The API path of the target's directory Returns ------- name : unicode A filename that is unique, based on the input filename. """ path = path.strip('/') basename, ext = os.path.splitext(filename) for i in itertools.count(): if i: insert_i = '{}{}'.format(insert, i) else: insert_i = '' name = u'{basename}{insert}{ext}'.format(basename=basename, insert=insert_i, ext=ext) if not self.exists(u'{}/{}'.format(path, name)): break return name def validate_notebook_model(self, model): """Add failed-validation message to model""" try: validate(model['content']) except ValidationError as e: model['message'] = u'Notebook Validation failed: {}:\n{}'.format( e.message, json.dumps(e.instance, indent=1, default=lambda obj: ''), ) return model def new_untitled(self, path='', type='', ext=''): """Create a new untitled file or directory in path path must be a directory File extension can be specified. Use `new` to create files with a fully specified path (including filename). """ path = path.strip('/') if not self.dir_exists(path): raise HTTPError(404, 'No such directory: %s' % path) model = {} if type: model['type'] = type if ext == '.ipynb': model.setdefault('type', 'notebook') else: model.setdefault('type', 'file') insert = '' if model['type'] == 'directory': untitled = self.untitled_directory insert = ' ' elif model['type'] == 'notebook': untitled = self.untitled_notebook ext = '.ipynb' elif model['type'] == 'file': untitled = self.untitled_file else: raise HTTPError(400, "Unexpected model type: %r" % model['type']) name = self.increment_filename(untitled + ext, path, insert=insert) path = u'{0}/{1}'.format(path, name) return self.new(model, path) def new(self, model=None, path=''): """Create a new file or directory and return its model with no content. To create a new untitled entity in a directory, use `new_untitled`. """ path = path.strip('/') if model is None: model = {} if path.endswith('.ipynb'): model.setdefault('type', 'notebook') else: model.setdefault('type', 'file') # no content, not a directory, so fill out new-file model if 'content' not in model and model['type'] != 'directory': if model['type'] == 'notebook': model['content'] = new_notebook() model['format'] = 'json' else: model['content'] = '' model['type'] = 'file' model['format'] = 'text' model = self.save(model, path) return model def copy(self, from_path, to_path=None): """Copy an existing file and return its new model. If to_path not specified, it will be the parent directory of from_path. If to_path is a directory, filename will increment `from_path-Copy#.ext`. from_path must be a full path to a file. """ path = from_path.strip('/') if to_path is not None: to_path = to_path.strip('/') if '/' in path: from_dir, from_name = path.rsplit('/', 1) else: from_dir = '' from_name = path model = self.get(path) model.pop('path', None) model.pop('name', None) if model['type'] == 'directory': raise HTTPError(400, "Can't copy directories") if to_path is None: to_path = from_dir if self.dir_exists(to_path): name = copy_pat.sub(u'.', from_name) to_name = self.increment_filename(name, to_path, insert='-Copy') to_path = u'{0}/{1}'.format(to_path, to_name) model = self.save(model, to_path) return model def log_info(self): self.log.info(self.info_string()) def trust_notebook(self, path): """Explicitly trust a notebook Parameters ---------- path : string The path of a notebook """ model = self.get(path) nb = model['content'] self.log.warn("Trusting notebook %s", path) self.notary.mark_cells(nb, True) self.save(model, path) def check_and_sign(self, nb, path=''): """Check for trusted cells, and sign the notebook. Called as a part of saving notebooks. Parameters ---------- nb : dict The notebook dict path : string The notebook's path (for logging) """ if self.notary.check_cells(nb): self.notary.sign(nb) else: self.log.warn("Saving untrusted notebook %s", path) def mark_trusted_cells(self, nb, path=''): """Mark cells as trusted if the notebook signature matches. Called as a part of loading notebooks. Parameters ---------- nb : dict The notebook object (in current nbformat) path : string The notebook's path (for logging) """ trusted = self.notary.check_signature(nb) if not trusted: self.log.warn("Notebook %s is not trusted", path) self.notary.mark_cells(nb, trusted) def should_list(self, name): """Should this file/directory name be displayed in a listing?""" return not any(fnmatch(name, glob) for glob in self.hide_globs) # Part 3: Checkpoints API def create_checkpoint(self, path): """Create a checkpoint.""" return self.checkpoints.create_checkpoint(self, path) def restore_checkpoint(self, checkpoint_id, path): """ Restore a checkpoint. """ self.checkpoints.restore_checkpoint(self, checkpoint_id, path) def list_checkpoints(self, path): return self.checkpoints.list_checkpoints(path) def delete_checkpoint(self, checkpoint_id, path): return self.checkpoints.delete_checkpoint(checkpoint_id, path)