fix: Improve randomness (#101)

.travis.yml

@@ -3,7 +3,6 @@ arch:
   - amd64
   - ppc64le
 python:
-  - "3.5"
   - "3.6"
   - "3.7"
   - "3.8"

README.md

@@ -18,7 +18,7 @@ Installation
 
 To install `shortuuid` you need:
 
--   Python 3.x.
+-   Python 3.6+
 
 If you have the dependencies, you have multiple options of installation:
 

pyproject.toml

@@ -6,7 +6,6 @@ license = "BSD-3-Clause"
 classifiers = [
   "License :: OSI Approved :: BSD License",
   "Programming Language :: Python",
-  "Programming Language :: Python :: 3.5",
   "Programming Language :: Python :: 3.6",
   "Programming Language :: Python :: 3.7",
   "Programming Language :: Python :: 3.8",
@@ -23,7 +22,7 @@ include = ["COPYING"]
 shortuuid = "shortuuid.cli:cli"
 
 [tool.poetry.dependencies]
-python = ">=3.5"
+python = ">=3.6"
 
 [build-system]
 requires = ["poetry-core"]

shortuuid/main.py

@@ -3,6 +3,7 @@
 import math
 import os
 import uuid as _uu
+import secrets
 from typing import List
 from typing import Optional
 
@@ -104,8 +105,7 @@ def random(self, length: Optional[int] = None) -> str:
         if length is None:
             length = self._length
 
-        random_num = int(binascii.b2a_hex(os.urandom(length)), 16)
-        return int_to_string(random_num, self._alphabet, padding=length)[:length]
+        return "".join(secrets.choice(self._alphabet) for _ in range(length))
 
     def get_alphabet(self) -> str:
         """Return the current alphabet used for new UUIDs."""