"""Notebook related utilities""" # Copyright (c) Jupyter Development Team. # Distributed under the terms of the Modified BSD License. import asyncio import errno import importlib.util import inspect import os import socket import sys from contextlib import contextmanager from urllib.parse import urljoin # noqa: F401 from urllib.parse import SplitResult, quote, unquote, urlparse, urlsplit, urlunsplit from urllib.request import pathname2url # noqa: F401 from _frozen_importlib_external import _NamespacePath from packaging.version import Version from tornado.httpclient import AsyncHTTPClient, HTTPClient, HTTPRequest from tornado.netutil import Resolver def url_path_join(*pieces): """Join components of url into a relative url Use to prevent double slash when joining subpath. This will leave the initial and final / in place """ initial = pieces[0].startswith("/") final = pieces[-1].endswith("/") stripped = [s.strip("/") for s in pieces] result = "/".join(s for s in stripped if s) if initial: result = "/" + result if final: result = result + "/" if result == "//": result = "/" return result def url_is_absolute(url): """Determine whether a given URL is absolute""" return urlparse(url).path.startswith("/") def path2url(path): """Convert a local file path to a URL""" pieces = [quote(p) for p in path.split(os.sep)] # preserve trailing / if pieces[-1] == "": pieces[-1] = "/" url = url_path_join(*pieces) return url def url2path(url): """Convert a URL to a local file path""" 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 = path.split("/") return "/".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 "/".join([unquote(p) for p in path.split("/")]) def samefile_simple(path, other_path): """ Fill in for os.path.samefile when it is unavailable (Windows+py2). Do a case-insensitive string comparison in this case plus comparing the full stat result (including times) because Windows + py2 doesn't support the stat fields needed for identifying if it's the same file (st_ino, st_dev). Only to be used if os.path.samefile is not available. Parameters ---------- path : String representing a path to a file other_path : String representing a path to another file Returns ------- same: Boolean that is True if both path and other path are the same """ path_stat = os.stat(path) other_path_stat = os.stat(other_path) return path.lower() == other_path.lower() and path_stat == other_path_stat def to_os_path(path, root=""): """Convert an API path to a filesystem path If given, root will be prepended to the path. root must be a filesystem path already. """ parts = path.strip("/").split("/") parts = [p for p in parts if p != ""] # remove duplicate splits path = os.path.join(root, *parts) return os.path.normpath(path) 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. """ if os_path.startswith(root): os_path = os_path[len(root) :] parts = os_path.strip(os.path.sep).split(os.path.sep) parts = [p for p in parts if p != ""] # remove duplicate splits path = "/".join(parts) return path def check_version(v, check): """check version string v >= check If dev/prerelease tags result in TypeError for string-number comparison, it is assumed that the dependency is satisfied. Users on dev branches are responsible for keeping their own packages up to date. """ try: return Version(v) >= Version(check) except TypeError: return True # Copy of IPython.utils.process.check_pid: def _check_pid_win32(pid): import ctypes # OpenProcess returns 0 if no such process (of ours) exists # positive int otherwise return bool(ctypes.windll.kernel32.OpenProcess(1, 0, pid)) # type:ignore[attr-defined] def _check_pid_posix(pid): """Copy of IPython.utils.process.check_pid""" try: os.kill(pid, 0) except OSError as err: if err.errno == errno.ESRCH: return False elif err.errno == errno.EPERM: # Don't have permission to signal the process - probably means it exists return True raise else: return True if sys.platform == "win32": check_pid = _check_pid_win32 else: check_pid = _check_pid_posix async def ensure_async(obj): """Convert a non-awaitable object to a coroutine if needed, and await it if it was not already awaited. """ if inspect.isawaitable(obj): try: result = await obj except RuntimeError as e: if str(e) == "cannot reuse already awaited coroutine": # obj is already the coroutine's result return obj raise return result # obj doesn't need to be awaited return obj def run_sync(maybe_async): """If async, runs maybe_async and blocks until it has executed, possibly creating an event loop. If not async, just returns maybe_async as it is the result of something that has already executed. Parameters ---------- maybe_async : async or non-async object The object to be executed, if it is async. Returns ------- result Whatever the async object returns, or the object itself. """ if not inspect.isawaitable(maybe_async): # that was not something async, just return it return maybe_async # it is async, we need to run it in an event loop def wrapped(): create_new_event_loop = False try: loop = asyncio.get_event_loop() except RuntimeError: create_new_event_loop = True else: if loop.is_closed(): create_new_event_loop = True if create_new_event_loop: loop = asyncio.new_event_loop() asyncio.set_event_loop(loop) try: result = loop.run_until_complete(maybe_async) except RuntimeError as e: if str(e) == "This event loop is already running": # just return a Future, hoping that it will be awaited result = asyncio.ensure_future(maybe_async) else: raise e return result return wrapped() async def run_sync_in_loop(maybe_async): """Runs a function synchronously whether it is an async function or not. If async, runs maybe_async and blocks until it has executed. If not async, just returns maybe_async as it is the result of something that has already executed. Parameters ---------- maybe_async : async or non-async object The object to be executed, if it is async. Returns ------- result Whatever the async object returns, or the object itself. """ if not inspect.isawaitable(maybe_async): return maybe_async return await maybe_async def urlencode_unix_socket_path(socket_path): """Encodes a UNIX socket path string from a socket path for the `http+unix` URI form.""" return socket_path.replace("/", "%2F") def urldecode_unix_socket_path(socket_path): """Decodes a UNIX sock path string from an encoded sock path for the `http+unix` URI form.""" return socket_path.replace("%2F", "/") def urlencode_unix_socket(socket_path): """Encodes a UNIX socket URL from a socket path for the `http+unix` URI form.""" return "http+unix://%s" % urlencode_unix_socket_path(socket_path) def unix_socket_in_use(socket_path): """Checks whether a UNIX socket path on disk is in use by attempting to connect to it.""" if not os.path.exists(socket_path): return False try: sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) sock.connect(socket_path) except OSError: return False else: return True finally: sock.close() @contextmanager def _request_for_tornado_client(urlstring, method="GET", body=None, headers=None): """A utility that provides a context that handles HTTP, HTTPS, and HTTP+UNIX request. Creates a tornado HTTPRequest object with a URL that tornado's HTTPClients can accept. If the request is made to a unix socket, temporarily configure the AsyncHTTPClient to resolve the URL and connect to the proper socket. """ parts = urlsplit(urlstring) if parts.scheme in ["http", "https"]: pass elif parts.scheme == "http+unix": # If unix socket, mimic HTTP. parts = SplitResult( scheme="http", netloc=parts.netloc, path=parts.path, query=parts.query, fragment=parts.fragment, ) class UnixSocketResolver(Resolver): """A resolver that routes HTTP requests to unix sockets in tornado HTTP clients. Due to constraints in Tornados' API, the scheme of the must be `http` (not `http+unix`). Applications should replace the scheme in URLS before making a request to the HTTP client. """ def initialize(self, resolver): self.resolver = resolver def close(self): self.resolver.close() async def resolve(self, host, port, *args, **kwargs): return [(socket.AF_UNIX, urldecode_unix_socket_path(host))] resolver = UnixSocketResolver(resolver=Resolver()) AsyncHTTPClient.configure(None, resolver=resolver) else: raise Exception("Unknown URL scheme.") # Yield the request for the given client. url = urlunsplit(parts) request = HTTPRequest(url, method=method, body=body, headers=headers) yield request def fetch(urlstring, method="GET", body=None, headers=None): """ Send a HTTP, HTTPS, or HTTP+UNIX request to a Tornado Web Server. Returns a tornado HTTPResponse. """ with _request_for_tornado_client( urlstring, method=method, body=body, headers=headers ) as request: response = HTTPClient(AsyncHTTPClient).fetch(request) return response async def async_fetch(urlstring, method="GET", body=None, headers=None, io_loop=None): """ Send an asynchronous HTTP, HTTPS, or HTTP+UNIX request to a Tornado Web Server. Returns a tornado HTTPResponse. """ with _request_for_tornado_client( urlstring, method=method, body=body, headers=headers ) as request: response = await AsyncHTTPClient(io_loop).fetch(request) return response def is_namespace_package(namespace): """Is the provided namespace a Python Namespace Package (PEP420). https://www.python.org/dev/peps/pep-0420/#specification Returns `None` if module is not importable. """ # NOTE: using submodule_search_locations because the loader can be None try: spec = importlib.util.find_spec(namespace) except ValueError: # spec is not set - see https://docs.python.org/3/library/importlib.html#importlib.util.find_spec return None if not spec: # e.g. module not installed return None return isinstance(spec.submodule_search_locations, _NamespacePath) def filefind(filename, path_dirs=None): """Find a file by looking through a sequence of paths. This iterates through a sequence of paths looking for a file and returns the full, absolute path of the first occurence of the file. If no set of path dirs is given, the filename is tested as is, after running through :func:`expandvars` and :func:`expanduser`. Thus a simple call:: filefind('myfile.txt') will find the file in the current working dir, but:: filefind('~/myfile.txt') Will find the file in the users home directory. This function does not automatically try any paths, such as the cwd or the user's home directory. Parameters ---------- filename : str The filename to look for. path_dirs : str, None or sequence of str The sequence of paths to look for the file in. If None, the filename need to be absolute or be in the cwd. If a string, the string is put into a sequence and the searched. If a sequence, walk through each element and join with ``filename``, calling :func:`expandvars` and :func:`expanduser` before testing for existence. Returns ------- Raises :exc:`IOError` or returns absolute path to file. """ # If paths are quoted, abspath gets confused, strip them... filename = filename.strip('"').strip("'") # If the input is an absolute path, just check it exists if os.path.isabs(filename) and os.path.isfile(filename): return filename if path_dirs is None: path_dirs = ("",) elif isinstance(path_dirs, str): path_dirs = (path_dirs,) for path in path_dirs: if path == ".": path = os.getcwd() testname = expand_path(os.path.join(path, filename)) if os.path.isfile(testname): return os.path.abspath(testname) raise OSError(f"File {filename!r} does not exist in any of the search paths: {path_dirs!r}") def expand_path(s): """Expand $VARS and ~names in a string, like a shell :Examples: In [2]: os.environ['FOO']='test' In [3]: expand_path('variable FOO is $FOO') Out[3]: 'variable FOO is test' """ # This is a pretty subtle hack. When expand user is given a UNC path # on Windows (\\server\share$\%username%), os.path.expandvars, removes # the $ to get (\\server\share\%username%). I think it considered $ # alone an empty var. But, we need the $ to remains there (it indicates # a hidden share). if os.name == "nt": s = s.replace("$\\", "IPYTHON_TEMP") s = os.path.expandvars(os.path.expanduser(s)) if os.name == "nt": s = s.replace("IPYTHON_TEMP", "$\\") return s def import_item(name): """Import and return ``bar`` given the string ``foo.bar``. Calling ``bar = import_item("foo.bar")`` is the functional equivalent of executing the code ``from foo import bar``. Parameters ---------- name : string The fully qualified name of the module/package being imported. Returns ------- mod : module object The module that was imported. """ parts = name.rsplit(".", 1) if len(parts) == 2: # called with 'foo.bar....' package, obj = parts module = __import__(package, fromlist=[obj]) try: pak = getattr(module, obj) except AttributeError: raise ImportError("No module named %s" % obj) return pak else: # called with un-dotted string return __import__(parts[0])