add test for random_hex and random_hex_with_timestamp

docs/source/api_doc/utils/index.rst

@@ -8,4 +8,5 @@ treevalue.utils
     enum
     final
     func
+    random
     singleton

docs/source/api_doc/utils/random.rst

+treevalue.utils.random
+============================
+
+seed_random
+~~~~~~~~~~~~~~~~~~
+
+.. autofunction:: treevalue.utils.random.seed_random
+
+
+random_hex
+~~~~~~~~~~~~~~~~~~~
+
+.. autofunction:: treevalue.utils.random.random_hex
+
+
+random_hex_with_timestamp
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autofunction:: treevalue.utils.random.random_hex_with_timestamp
+

test/utils/test_random.py

+import re
+
 import pytest
 
-from treevalue.utils import seed_random
+from treevalue.utils import seed_random, random_hex, random_hex_with_timestamp
 
 
 @pytest.mark.unittest
@@ -13,3 +15,11 @@ class TestUtilsRandom:
         with seed_random(233) as rnd:
             a, b, c = rnd.randint(0x00, 0xff), rnd.randint(0x00, 0xff), rnd.randint(0x00, 0xff)
         assert (a, b, c) == (89, 118, 247)
+
+    def test_random_hex(self):
+        assert re.fullmatch(r'^[a-f0-9]{32}$', random_hex())
+        assert re.fullmatch(r'^[a-f0-9]{48}$', random_hex(48))
+
+    def test_random_hex_with_timestamp(self):
+        assert re.fullmatch(r'^\d{8}_\d{12}_[a-f0-9]{12}$', random_hex_with_timestamp())
+        assert re.fullmatch(r'^\d{8}_\d{12}_[a-f0-9]{48}$', random_hex_with_timestamp(48))

treevalue/utils/__init__.py

@@ -2,6 +2,6 @@ from .clazz import init_magic, class_wraps, common_bases, common_direct_base
 from .enum import int_enum_loads
 from .final import FinalMeta
 from .func import args_iter, dynamic_call
-from .random import seed_random
+from .random import seed_random, random_hex, random_hex_with_timestamp
 from .singleton import SingletonMeta, ValueBasedSingletonMeta, SingletonMark
 from .tree import build_tree

treevalue/utils/random.py

+import random
 from contextlib import contextmanager
+from datetime import datetime
 from random import Random
 
 
@@ -11,9 +13,43 @@ def seed_random(seed):
     Arguments:
         - seed (:obj:`int`): Random seed, should be a `int`.
     """
-    random = Random()
-    random.seed(seed)
+    rnd = Random()
+    rnd.seed(seed)
     try:
-        yield random
+        yield rnd
     finally:
-        random.seed()
+        rnd.seed()
+
+
+def random_hex(length: int = 32) -> str:
+    """
+    Overview:
+        Generate random hex string.
+
+    Arguments:
+        - length (:obj:`int`): Length of hex string, default is `32`.
+
+    Returns:
+        - string (:obj:`str`): Generated string.
+
+    Examples:
+        >>> random_hex()  # 'ca7f14b25aa4498efdacb54e9ff72784'
+    """
+    return ''.join([hex(random.randint(0, 15))[2:] for _ in range(length)])
+
+
+def random_hex_with_timestamp(length: int = 12) -> str:
+    """
+    Overview:
+        Generate random hex string, with prefix of timestamp.
+
+    Arguments:
+        - length (:obj:`int`): Length of hex string, default is `12`.
+
+    Returns:
+        - string (:obj:`str`): Generated string.
+
+    Examples:
+        >>> random_hex_with_timestamp()  # '20210729_202059576266_69603d64afad'
+    """
+    return datetime.now().strftime("%Y%m%d_%H%M%S%f") + "_" + random_hex(length)

treevalue/utils/tree.py

+import re
 from queue import Queue
 
+from graphviz import Digraph
 from treelib import Tree as LibTree
 
+from .random import random_hex_with_timestamp
+
 _ROOT_ID = '_root'
 _NODE_ID_TEMP = '_node_{id}'
 
@@ -31,3 +35,23 @@ def build_tree(root, represent=None, iterate=None, recurse=None) -> LibTree:
                 _queue.put((_current_id, value))
 
     return _tree
+
+
+_NAME_PATTERN = re.compile('^[a-zA-Z_][a-zA-Z0-9_]*$')
+
+
+def _title_flatten(title):
+    title = re.sub(r'[^a-zA-Z0-9_]+', '_', str(title))
+    title = re.sub(r'_+', '_', title)
+    title = title.strip('_').lower()
+    return title
+
+
+def build_graph(root, name=None, title=None, represent=None, iterate=None, recurse=None):
+    represent = represent or repr
+    iterate = iterate or (lambda x: x.items())
+    recurse = recurse or (lambda x: hasattr(x, 'items'))
+
+    title = title or 'untitled_' + random_hex_with_timestamp()
+    name = name or _title_flatten(title)
+    graph = Digraph(name=name, comment=title)