Merge pull request #527 from meejah/492.attrs-deprecated

incorporate deprecated attrs code

NEWS.md

@@ -3,6 +3,7 @@ User-visible changes in "magic-wormhole":
 ## Upcoming Release
 
 * add release-notes here when making PRs
+* Incorporate attrs' zope-interface support (#492)
 
 
 ## Release 0.14.0 (28-Mar-2024)

src/wormhole/_allocator.py

@@ -1,7 +1,7 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from attr import attrib, attrs
-from attr.validators import provides
+from wormhole.util import provides
 from automat import MethodicalMachine
 from zope.interface import implementer
 

src/wormhole/_boss.py

@@ -1,7 +1,7 @@
 import re
 
 from attr import attrib, attrs
-from attr.validators import instance_of, optional, provides
+from attr.validators import instance_of, optional
 from automat import MethodicalMachine
 from twisted.python import log
 from zope.interface import implementer
@@ -23,7 +23,7 @@ from ._terminator import Terminator
 from ._wordlist import PGPWordList
 from .errors import (LonelyError, OnlyOneCodeError, ServerError, WelcomeError,
                      WrongPasswordError, _UnknownPhaseError)
-from .util import bytes_to_dict
+from .util import bytes_to_dict, provides
 
 
 @attrs

src/wormhole/_code.py

@@ -1,11 +1,11 @@
 from __future__ import print_function, absolute_import, unicode_literals
 from zope.interface import implementer
 from attr import attrs, attrib
-from attr.validators import provides
 from automat import MethodicalMachine
 from . import _interfaces
 from ._nameplate import validate_nameplate
 from .errors import KeyFormatError
+from .util import provides
 
 
 def validate_code(code):

src/wormhole/_dilation/connection.py

@@ -1,6 +1,6 @@
 from collections import namedtuple
 from attr import attrs, attrib
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from automat import MethodicalMachine
 from zope.interface import Interface, implementer
 from twisted.python import log
@@ -8,6 +8,7 @@ from twisted.internet.protocol import Protocol
 from twisted.internet.interfaces import ITransport
 from .._interfaces import IDilationConnector
 from ..observer import OneShotObserver
+from ..util import provides
 from .encode import to_be4, from_be4
 from .roles import LEADER, FOLLOWER
 from ._noise import NoiseInvalidMessage, NoiseHandshakeError, NOISE_MAX_PAYLOAD, NOISE_MAX_CIPHERTEXT

src/wormhole/_dilation/connector.py

@@ -2,7 +2,7 @@ from __future__ import print_function, unicode_literals
 from collections import defaultdict
 from binascii import hexlify
 from attr import attrs, attrib
-from attr.validators import instance_of, provides, optional
+from attr.validators import instance_of, optional
 from automat import MethodicalMachine
 from zope.interface import implementer
 from twisted.internet.task import deferLater
@@ -16,7 +16,7 @@ from .. import ipaddrs  # TODO: move into _dilation/
 from .._interfaces import IDilationConnector, IDilationManager
 from ..timing import DebugTiming
 from ..observer import EmptyableSet
-from ..util import HKDF, to_unicode
+from ..util import HKDF, to_unicode, provides
 from .connection import DilatedConnectionProtocol, KCM
 from .roles import LEADER
 

src/wormhole/_dilation/inbound.py

@@ -1,9 +1,9 @@
 from __future__ import print_function, unicode_literals
 from attr import attrs, attrib
-from attr.validators import provides
 from zope.interface import implementer
 from twisted.python import log
 from .._interfaces import IDilationManager, IInbound, ISubChannel
+from ..util import provides
 from .subchannel import (SubChannel, _SubchannelAddress)
 
 

src/wormhole/_dilation/manager.py

@@ -2,7 +2,7 @@ import os
 from collections import deque
 from collections.abc import Sequence
 from attr import attrs, attrib
-from attr.validators import provides, instance_of, optional
+from attr.validators import instance_of, optional
 from automat import MethodicalMachine
 from zope.interface import implementer
 from twisted.internet.defer import Deferred
@@ -10,7 +10,7 @@ from twisted.internet.interfaces import (IStreamClientEndpoint,
                                          IStreamServerEndpoint)
 from twisted.python import log, failure
 from .._interfaces import IDilator, IDilationManager, ISend, ITerminator
-from ..util import dict_to_bytes, bytes_to_dict, bytes_to_hexstr
+from ..util import dict_to_bytes, bytes_to_dict, bytes_to_hexstr, provides
 from ..observer import OneShotObserver
 from .._key import derive_key
 from .subchannel import (SubChannel, _SubchannelAddress, _WormholeAddress,

src/wormhole/_dilation/outbound.py

@@ -1,12 +1,12 @@
 from __future__ import print_function, unicode_literals
 from collections import deque
 from attr import attrs, attrib
-from attr.validators import provides
 from zope.interface import implementer
 from twisted.internet.interfaces import IPushProducer, IPullProducer
 from twisted.python import log
 from twisted.python.reflect import safe_str
 from .._interfaces import IDilationManager, IOutbound
+from ..util import provides
 from .connection import KCM, Ping, Pong, Ack
 
 

src/wormhole/_dilation/subchannel.py

@@ -1,6 +1,6 @@
 from collections import deque
 from attr import attrs, attrib
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from zope.interface import implementer
 from twisted.internet.defer import inlineCallbacks, returnValue
 from twisted.internet.interfaces import (ITransport, IProducer, IConsumer,
@@ -12,6 +12,7 @@ from twisted.internet.error import ConnectionDone
 from automat import MethodicalMachine
 from .._interfaces import ISubChannel, IDilationManager
 from ..observer import OneShotObserver
+from ..util import provides
 
 # each subchannel frame (the data passed into transport.write(data)) gets a
 # 9-byte header prefix (type, subchannel id, and sequence number), then gets

src/wormhole/_input.py

@@ -6,14 +6,13 @@ from __future__ import absolute_import, print_function, unicode_literals
 import threading
 
 from attr import attrib, attrs
-from attr.validators import provides
 from automat import MethodicalMachine
 from twisted.internet import defer
 from zope.interface import implementer
 
 from . import _interfaces, errors
 from ._nameplate import validate_nameplate
-
+from .util import provides
 
 def first(outputs):
     return list(outputs)[0]

src/wormhole/_key.py

@@ -1,7 +1,7 @@
 from hashlib import sha256
 
 from attr import attrib, attrs
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from automat import MethodicalMachine
 from nacl import utils
 from nacl.exceptions import CryptoError
@@ -11,7 +11,7 @@ from zope.interface import implementer
 
 from . import _interfaces
 from .util import (bytes_to_dict, bytes_to_hexstr, dict_to_bytes,
-                   hexstr_to_bytes, to_bytes, HKDF)
+                   hexstr_to_bytes, to_bytes, HKDF, provides)
 
 CryptoError
 __all__ = ["derive_key", "derive_phase_key", "CryptoError", "Key"]

src/wormhole/_lister.py

@@ -1,11 +1,11 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from attr import attrib, attrs
-from attr.validators import provides
 from automat import MethodicalMachine
 from zope.interface import implementer
 
 from . import _interfaces
+from .util import provides
 
 
 @attrs

src/wormhole/_order.py

@@ -1,11 +1,12 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from attr import attrib, attrs
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from automat import MethodicalMachine
 from zope.interface import implementer
 
 from . import _interfaces
+from .util import provides
 
 
 @attrs

src/wormhole/_receive.py

@@ -1,12 +1,13 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from attr import attrib, attrs
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from automat import MethodicalMachine
 from zope.interface import implementer
 
 from . import _interfaces
 from ._key import CryptoError, decrypt_data, derive_key, derive_phase_key
+from .util import provides
 
 
 @attrs

src/wormhole/_rendezvous.py

@@ -1,7 +1,7 @@
 import os
 from urllib.parse import urlparse
 from attr import attrs, attrib
-from attr.validators import provides, instance_of, optional
+from attr.validators import instance_of, optional
 from zope.interface import implementer
 from twisted.python import log
 from twisted.internet import defer, endpoints, task
@@ -9,7 +9,7 @@ from twisted.application import internet
 from autobahn.twisted import websocket
 from . import _interfaces, errors
 from .util import (bytes_to_hexstr, hexstr_to_bytes, bytes_to_dict,
-                   dict_to_bytes)
+                   dict_to_bytes, provides)
 
 
 class WSClient(websocket.WebSocketClientProtocol):

src/wormhole/_send.py

@@ -1,12 +1,13 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from attr import attrib, attrs
-from attr.validators import instance_of, provides
+from attr.validators import instance_of
 from automat import MethodicalMachine
 from zope.interface import implementer
 
 from . import _interfaces
 from ._key import derive_phase_key, encrypt_data
+from .util import provides
 
 
 @attrs

src/wormhole/test/test_util_attrs_zope.py

@@ -0,0 +1,73 @@
+import zope.interface
+from twisted.trial import unittest
+from attr import Attribute
+from attr._make import NOTHING
+from wormhole.util import provides
+
+
+class IFoo(zope.interface.Interface):
+    """
+    An interface.
+    """
+
+    def f():
+        """
+        A function called f.
+        """
+
+
+def simple_attr(name):
+    return Attribute(
+        name=name,
+        default=NOTHING,
+        validator=None,
+        repr=True,
+        cmp=None,
+        eq=True,
+        hash=None,
+        init=True,
+        converter=None,
+        kw_only=False,
+        inherited=False,
+    )
+
+
+class TestProvides(unittest.TestCase):
+    """
+    Tests for `provides`.
+    """
+
+    def test_success(self):
+        """
+        Nothing happens if value provides requested interface.
+        """
+
+        @zope.interface.implementer(IFoo)
+        class C(object):
+            def f(self):
+                pass
+
+        v = provides(IFoo)
+        v(None, simple_attr("x"), C())
+
+    def test_fail(self):
+        """
+        Raises `TypeError` if interfaces isn't provided by value.
+        """
+        value = object()
+        a = simple_attr("x")
+
+        v = provides(IFoo)
+        with self.assertRaises(TypeError):
+            v(None, a, value)
+
+    def test_repr(self):
+        """
+        Returned validator has a useful `__repr__`.
+        """
+        v = provides(IFoo)
+        assert (
+            "<provides validator for interface {interface!r}>".format(
+                interface=IFoo
+            )
+        ) == repr(v)

src/wormhole/util.py

@@ -5,6 +5,7 @@ import unicodedata
 from binascii import hexlify, unhexlify
 from cryptography.hazmat.primitives.kdf import hkdf
 from cryptography.hazmat.primitives import hashes
+from attr import attrs, attrib
 
 
 def HKDF(skm, outlen, salt=None, CTXinfo=b""):
@@ -77,3 +78,42 @@ def estimate_free_space(target):
         return s.f_frsize * s.f_bfree
     except AttributeError:
         return None
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _ProvidesValidator:
+    interface = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not self.interface.providedBy(value):
+            msg = "'{name}' must provide {interface!r} which {value!r} doesn't.".format(
+                name=attr.name, interface=self.interface, value=value
+            )
+            raise TypeError(
+                msg,
+                attr,
+                self.interface,
+                value,
+            )
+
+    def __repr__(self):
+        return f"<provides validator for interface {self.interface!r}>"
+
+
+def provides(interface):
+    """
+    A validator that raises a `TypeError` if the initializer is called
+    with an object that does not provide the requested *interface* (checks are
+    performed using ``interface.providedBy(value)``.
+
+    :param interface: The interface to check for.
+    :type interface: ``zope.interface.Interface``
+
+    :raises TypeError: With a human readable error message, the attribute
+        (of type `attrs.Attribute`), the expected interface, and the
+        value it got.
+    """
+    return _ProvidesValidator(interface)