mirror of https://github.com/jumpserver/jumpserver
107 lines
3.1 KiB
Python
107 lines
3.1 KiB
Python
# -*- coding: utf-8 -*-
|
||
#
|
||
from itertools import chain
|
||
from .utils import lazyproperty
|
||
|
||
|
||
class Stack(list):
|
||
def is_empty(self):
|
||
return len(self) == 0
|
||
|
||
@property
|
||
def top(self):
|
||
if self.is_empty():
|
||
return None
|
||
return self[-1]
|
||
|
||
@property
|
||
def bottom(self):
|
||
if self.is_empty():
|
||
return None
|
||
return self[0]
|
||
|
||
def size(self):
|
||
return len(self)
|
||
|
||
def push(self, item):
|
||
self.append(item)
|
||
|
||
|
||
class QuerySetChain:
|
||
def __init__(self, querysets):
|
||
self.querysets = querysets
|
||
|
||
@lazyproperty
|
||
def querysets_counts(self):
|
||
counts = [s.count() for s in self.querysets]
|
||
return counts
|
||
|
||
def count(self):
|
||
return self.total_count
|
||
|
||
@lazyproperty
|
||
def total_count(self):
|
||
return sum(self.querysets_counts)
|
||
|
||
def __iter__(self):
|
||
self._chain = chain(*self.querysets)
|
||
return self
|
||
|
||
def __next__(self):
|
||
return next(self._chain)
|
||
|
||
def __getitem__(self, ndx):
|
||
querysets_count_zip = zip(self.querysets, self.querysets_counts)
|
||
length = 0 # 加上本数组后的大数组长度
|
||
pre_length = 0 # 不包含本数组的大数组长度
|
||
items = [] # 返回的值
|
||
loop = 0
|
||
|
||
if isinstance(ndx, slice):
|
||
ndx_start = ndx.start or 0
|
||
ndx_stop = ndx.stop or self.total_count
|
||
ndx_step = ndx.step or 1
|
||
else:
|
||
ndx_start = ndx
|
||
ndx_stop, ndx_step = None, None
|
||
|
||
for queryset, count in querysets_count_zip:
|
||
length += count
|
||
loop += 1
|
||
# 取当前数组的start角标, 存在3中情况
|
||
# 1. start角标在当前数组
|
||
if length > ndx_start >= pre_length:
|
||
start = ndx_start - pre_length
|
||
# print("[loop {}] Start is: {}".format(loop, start))
|
||
if ndx_step is None:
|
||
return queryset[start]
|
||
# 2. 不包含当前数组，因为起始已经超过了当前数组的长度
|
||
elif ndx_start >= length:
|
||
pre_length += count
|
||
continue
|
||
# 3. 不在当前数组，但是应该从当前数组0开始计算
|
||
else:
|
||
start = 0
|
||
|
||
# 可能取单个值, ndx_stop 为None, 不应该再找
|
||
if ndx_stop is None:
|
||
pre_length += count
|
||
continue
|
||
|
||
# 取当前数组的stop角标, 存在2中情况
|
||
# 不存在第3中情况是因为找到了会提交结束循环
|
||
# 1. 结束角标小于length代表 结束位在当前数组上
|
||
if ndx_stop < length:
|
||
stop = ndx_stop - pre_length
|
||
# 2. 结束位置包含改数组到了最后
|
||
else:
|
||
stop = count
|
||
# print("[loop {}] Slice: {} {} {}".format(loop, start, stop, ndx_step))
|
||
items.extend(list(queryset[slice(start, stop, ndx_step)]))
|
||
pre_length += count
|
||
|
||
# 如果结束再当前数组，则结束循环
|
||
if ndx_stop < length:
|
||
break
|
||
return items
|