Make the package friendlier as a dependency

CHANGELOG.rst

@@ -8,13 +8,36 @@ All notable changes to this project will be documented in this file.
 The format is based on `Keep a Changelog`_, and this project adheres to
 `Semantic Versioning`_.
 
-`Unreleased`_
--------------
+`0.3.0`_ - 2024-05-15
+---------------------
+
+Incompatible
+~~~~~~~~~~~~
+
+- The `shamir` command no longer works out of the box. It is necessary to install the
+  `cli` extra while installing the package. See README for instructions.
+
+Added
+~~~~~
 
 - Added BIP32 master extended private key to test vectors.
 - Added support for extendable backup flag.
 
-.. _Unreleased: https://github.com/trezor/python-shamir-mnemonic/compare/v0.2.2...HEAD
+Changed
+~~~~~~~
+
+- The `shamir_mnemonic` package now has zero extra dependencies on Python 3.7 and up,
+  making it more suitable as a dependency of other projects.
+- The `shamir` CLI still requires `click`. A new extra `cli` was introduced to handle
+  this dependency. Use the command `pip install shamir-mnemonic[cli]` to install the CLI
+  dependencies along with the package.
+
+Removed
+~~~~~~~
+
+- Removed dependency on `attrs`.
+
+.. _0.3.0: https://github.com/trezor/python-shamir-mnemonic/compare/v0.2.2...v0.3.0
 
 
 `0.2.2`_ - 2021-12-07

README.rst

@@ -35,11 +35,11 @@ not be used for handling sensitive secrets**.
 Installation
 ------------
 
-With pip from GitHub:
+With pip from PyPI:
 
 .. code-block:: console
 
-    $ pip3 install shamir-mnemonic
+    $ pip3 install shamir-mnemonic[cli]  # for CLI tool
 
 From local checkout for development:
 

generate_vectors.py

@@ -1,8 +1,8 @@
 #!/usr/bin/env python3
 import json
 import random
+from dataclasses import astuple
 
-import attr
 from bip32utils import BIP32Key
 
 from shamir_mnemonic import constants, rs1024, shamir, wordlist
@@ -24,7 +24,7 @@ def encode_mnemonic(*args):
 
 
 def decode_mnemonic(mnemonic):
-    return list(attr.astuple(Share.from_mnemonic(mnemonic)))
+    return list(astuple(Share.from_mnemonic(mnemonic)))
 
 
 def generate_mnemonics_random(group_threshold, groups):

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "shamir-mnemonic"
-version = "0.2.3"
+version = "0.3.0"
 description = "SLIP-39 Shamir Mnemonics"
 authors = ["Trezor <[email protected]>"]
 license = "MIT"
@@ -11,14 +11,18 @@ readme = [
 
 [tool.poetry.dependencies]
 python = ">=3.6,<4.0"
-click = ">=7,<9"
-bip32utils = "^0.3.post4"
-pytest = "*"
+dataclasses = { version = "*", python = "<=3.6" }
+click = { version = ">=7,<9", optional = true }
 
 [tool.poetry.group.dev.dependencies]
+bip32utils = "^0.3.post4"
+pytest = "*"
 black = ">=20"
 isort = "^5"
 
+[tool.poetry.extras]
+cli = ["click"]
+
 [tool.poetry.scripts]
 shamir = "shamir_mnemonic.cli:cli"
 

shamir_mnemonic/cli.py

@@ -2,8 +2,14 @@
 import sys
 from typing import Sequence, Tuple
 
-import click
-from click import style
+try:
+    import click
+    from click import style
+
+except ImportError:
+    print("Required dependencies are missing. Install them with:")
+    print("  pip install shamir_mnemonic[cli]")
+    sys.exit(1)
 
 from .recovery import RecoveryState
 from .shamir import generate_mnemonics

shamir_mnemonic/recovery.py

@@ -1,8 +1,7 @@
 from collections import defaultdict
+from dataclasses import dataclass, field, replace
 from typing import Any, Dict, Optional, Tuple
 
-import attr
-
 from .constants import GROUP_PREFIX_LENGTH_WORDS
 from .shamir import ShareGroup, recover_ems
 from .share import Share, ShareCommonParameters
@@ -24,7 +23,7 @@ def group_prefix(self, group_index: int) -> str:
         if not self.last_share:
             raise RuntimeError("Add at least one share first")
 
-        fake_share = attr.evolve(self.last_share, group_index=group_index)
+        fake_share = replace(self.last_share, group_index=group_index)
         return " ".join(fake_share.words()[:GROUP_PREFIX_LENGTH_WORDS])
 
     def group_status(self, group_index: int) -> Tuple[int, int]:

shamir_mnemonic/shamir.py

@@ -21,10 +21,9 @@
 
 import hmac
 import secrets
+from dataclasses import dataclass
 from typing import Any, Dict, Iterable, Iterator, List, NamedTuple, Sequence, Set, Tuple
 
-import attr
-
 from . import cipher
 from .constants import (
     DIGEST_INDEX,
@@ -101,7 +100,7 @@ def is_complete(self) -> bool:
             return False
 
 
-@attr.s(auto_attribs=True, frozen=True)
+@dataclass(frozen=True)
 class EncryptedMasterSecret:
     identifier: int
     extendable: bool

shamir_mnemonic/share.py

@@ -1,7 +1,6 @@
+from dataclasses import dataclass
 from typing import Iterable, List, NamedTuple
 
-import attr
-
 from . import rs1024, wordlist
 from .constants import (
     CUSTOMIZATION_STRING_EXTENDABLE,
@@ -61,7 +60,7 @@ class ShareGroupParameters(NamedTuple):
     member_threshold: int
 
 
-@attr.s(auto_attribs=True, frozen=True)
+@dataclass(frozen=True)
 class Share:
     """Represents a single mnemonic share and its metadata"""