本文目录导读：
我来详细说明Python迭代工具（itertools）的封装方法,以及如何实现版本迭代管理。
基础迭代器封装示例
from itertools import chain, cycle, permutations, combinations
from typing import Iterator, List, Any
class ItertoolsWrapper:
"""itertools功能封装"""
def __init__(self, data: List[Any] = None):
self.data = data or []
def chained(self, *iterables) -> Iterator:
"""链式连接多个迭代器"""
return chain(*iterables)
def cycled(self, times: int = None) -> Iterator:
"""循环迭代，可选择次数"""
if times:
return (x for _ in range(times) for x in cycle(self.data))
return cycle(self.data)
def all_permutations(self, r: int = None) -> Iterator:
"""获取所有排列"""
return permutations(self.data, r)
def all_combinations(self, r: int) -> Iterator:
"""获取所有组合"""
return combinations(self.data, r)
版本迭代管理类
from itertools import cycle, count
from typing import Tuple, Generator
class VersionIterator:
"""版本迭代器管理"""
def __init__(self, major: int = 1, minor: int = 0, patch: int = 0):
self.version = [major, minor, patch]
self.version_types = ['major', 'minor', 'patch']
def increment(self, version_type: str = 'patch') -> Tuple[int, int, int]:
"""递增版本号"""
idx = self.version_types.index(version_type)
self.version[idx] += 1
# 重置更小的版本号
for i in range(idx + 1, len(self.version)):
self.version[i] = 0
return tuple(self.version)
def generate_versions(self) -> Generator:
"""生成器方式产生版本号"""
while True:
yield tuple(self.version)
self.version[2] += 1 # 默认递增patch
if self.version[2] == 10: # patch达到10后升minor
self.version[1] += 1
self.version[2] = 0
if self.version[1] == 10: # minor达到10后升major
self.version[0] += 1
self.version[1] = 0
class VersionHistory:
"""版本历史管理器"""
def __init__(self):
self.history = []
self.current_version = None
def add_version(self, version: Tuple[int, int, int],
features: List[str] = None):
"""添加版本记录"""
self.current_version = version
self.history.append({
'version': '.'.join(map(str, version)),
'features': features or [],
'changelog': f"Version {'.'.join(map(str, version))}"
})
def get_version(self, version_str: str) -> dict:
"""获取特定版本信息"""
for v in self.history:
if v['version'] == version_str:
return v
return None
def diff_versions(self, v1: str, v2: str) -> dict:
"""比较两个版本的差异"""
ver1 = self.get_version(v1)
ver2 = self.get_version(v2)
if ver1 and ver2:
return {
'added': set(ver2['features']) - set(ver1['features']),
'removed': set(ver1['features']) - set(ver2['features'])
}
return None
复杂迭代器封装
from itertools import product, groupby, islice, filterfalse, takewhile, dropwhile
from functools import partial
from typing import Callable, Dict
class AdvancedIterator:
"""高级迭代器封装"""
def __init__(self):
self._operations = []
def pipe(self, func: Callable, *args, **kwargs):
"""链式管道操作"""
self._operations.append(partial(func, *args, **kwargs))
return self
def process(self, data: List) -> List:
"""执行管道操作"""
result = data
for op in self._operations:
result = list(op(result))
return result
@staticmethod
def batch_process(data: List, batch_size: int = 100) -> Generator:
"""批量处理数据"""
it = iter(data)
while True:
batch = list(islice(it, batch_size))
if not batch:
break
yield batch
class IteratorFactory:
"""迭代器工厂模式"""
_iterators = {
'cycle': cycle,
'count': count,
'chain': chain,
'product': product,
'groupby': groupby
}
@classmethod
def create_iterator(cls, name: str, *args, **kwargs):
"""创建指定类型的迭代器"""
if name not in cls._iterators:
raise ValueError(f"Unsupported iterator type: {name}")
return cls._iterators[name](*args, **kwargs)
@classmethod
def register(cls, name: str, iterator_class):
"""注册新的迭代器类型"""
cls._iterators[name] = iterator_class
实际应用案例
# 示例：数据版本迭代处理
class DataVersionProcessor:
"""数据版本处理器"""
def __init__(self, data: List[Dict]):
self.data = data
self.version_mgr = VersionIterator()
self.version_history = VersionHistory()
def process_with_version(self, transformation: Callable) -> Dict:
"""带版本控制的数据处理"""
# 获取当前版本
version = self.version_mgr.increment('minor')
# 应用转换
processed_data = list(map(transformation, self.data))
# 记录版本历史
self.version_history.add_version(
version,
features=[f"Applied {transformation.__name__}"]
)
return {
'version': '.'.join(map(str, version)),
'data': processed_data,
'changelog': self.version_history.history[-1]['changelog']
}
# 使用示例
if __name__ == "__main__":
# 创建版本迭代器
ver_iter = VersionIterator()
print("Version generation:")
for i in range(5):
print(f" {ver_iter.increment()}")
# 创建迭代器包装器
wrapper = ItertoolsWrapper([1, 2, 3])
print("\nCombinations:", list(wrapper.all_combinations(2)))
# 高级迭代器使用
adv_iter = AdvancedIterator()
result = adv_iter.pipe(filter, lambda x: x > 0)\
.pipe(sorted, reverse=True)\
.process([3, -1, 2, 5, -3, 1])
print("\nFiltered and sorted:", result)
# 数据版本处理
processor = DataVersionProcessor([
{'name': 'item1', 'value': 10},
{'name': 'item2', 'value': 20}
])
result = processor.process_with_version(
lambda x: {**x, 'value': x['value'] * 2}
)
print("\nProcessed with version:", result)
高级特性实现
from itertools import tee, accumulate, compress, dropwhile, zip_longest
import asyncio
from typing import AsyncIterator
class AsyncVersionIterator:
"""异步版本迭代器"""
def __init__(self, versions: List[Tuple[int, int, int]]):
self.versions = versions
async def __aiter__(self):
self._index = 0
return self
async def __anext__(self):
if self._index >= len(self.versions):
raise StopAsyncIteration
version = self.versions[self._index]
self._index += 1
await asyncio.sleep(0.1) # 模拟异步操作
return version
class IteratorChain:
"""迭代器链，支持复杂操作"""
def __init__(self):
self._iterators = []
self._processors = []
def add_source(self, iterator):
"""添加数据源"""
self._iterators.append(iterator)
return self
def add_processor(self, func):
"""添加处理器"""
self._processors.append(func)
return self
def execute(self):
"""执行迭代器链"""
current = chain(*self._iterators)
for processor in self._processors:
current = processor(current)
return current
测试和验证
import unittest
class TestIteratorTools(unittest.TestCase):
"""迭代器工具测试"""
def setUp(self):
self.wrapper = ItertoolsWrapper([1, 2, 3])
self.version_mgr = VersionIterator()
def test_version_increment(self):
"""测试版本递增"""
versions = []
for _ in range(5):
versions.append(self.version_mgr.increment())
self.assertEqual(len(versions), 5)
self.assertEqual(versions[-1], (1, 0, 5))
def test_combinations(self):
"""测试组合"""
combs = list(self.wrapper.all_combinations(2))
self.assertEqual(len(combs), 3)
self.assertIn((1, 2), combs)
def test_pipeline(self):
"""测试管道操作"""
adv = AdvancedIterator()
result = adv.pipe(lambda x: [i*2 for i in x]).process([1,2,3])
self.assertEqual(result, [2, 4, 6])
if __name__ == "__main__":
unittest.main()
这个封装方案提供了：
- 基础封装：将itertools函数封装成易用的接口
- 版本管理：完整的版本控制逻辑
- 链式操作：支持管道式和链式调用
- 工厂模式：灵活创建不同类型的迭代器
- 异步支持：异步版本迭代器
- 历史记录：版本历史追踪和比较
- 测试覆盖：单元测试确保功能正确
可以根据具体需求选择使用不同的封装层次和功能组合。
