我正在查询一个返回包含大量元素的XML输出的系统，但是我很难仅获取某些项目。
当我仅基于标签host_sn进行搜索时，它仅添加名称为host_sn且快照仅包含第0代的快照，而存在许多代。下面的xml输出以及示例生成0和1。
我如何遍历子元素并将所有世代和快照名称放入字典中。下面是我想要的输出示例。
我想要的输出：
#There should only be generation 0,1,2,3,etc.. never will see two gen 0,1,2
[{'generation': '0', 'timestamp': 'Thu Mar 26 22:10:55 2020', 'snapshot_link': 'No', 'snapshot_name': 'host_sn'}]
[{'generation': '1', 'timestamp': 'Thu Mar 26 22:20:55 2020', 'snapshot_link': 'No', 'snapshot_name': 'host_sn'}]
[{'generation': '2', 'timestamp': 'Thu Mar 26 22:30:55 2020', 'snapshot_link': 'No', 'snapshot_name': 'host_sn'}]
我只将第0代附加到字典中的代码（我玩过这个代码，并且会添加所有项，而不是像上面期望的输出那样添加唯一项：
snapshot = []
#Using python Elementree, run_to_xml just adds -output xml_element in the command
#example cmd: snapcmd -sg host_sg list -detail -output xml_element -sid 6161
snap_xml = self.run_to_xml("snapcmd -sg " + source_sg + " list -detail", True)
if snap_xml is not None:
for sn_item in snap_xml.findall('SG/Snapvx/Snapshot'):
sn_name = sn_item.find('snapshot_name').text
sn_timestamp = sn_item.find('timestamp').text
sn_generation = sn_item.find('generation').text
sn_link = sn_item.find('link').text
sn_list = {}
if sn_name.endswith(SNAPSHOTVX_NAME_POSTFIX): #Postfix is _sn
if sn_name not in [sn_list['snapshot_name'] for sn_list in snapshot]:
sn_list['generation'] = sn_generation
sn_list['snapshot_name'] = sn_name
sn_list['timestamp'] = sn_timestamp
sn_list['snapshot_link'] = sn_link
snapshot.append(sn_list)
XML输出示例：
<?xml version="1.0" standalone="yes" ?>
<SymCLI_ML>
<SG>
<SG_Info>
<name>host_sn</name>
<symid>0001##00####</symid>
<microcode_version>6161</microcode_version>
</SG_Info>
<Snapvx>
<Snapshot>
<source>000F9</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 16:05:37 2020</timestamp>
<generation>0</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>34</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>268</total_deltas_tracks>
<non_shared_mb>10</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>76</non_shared_tracks>
<expiration_date>Fri Mar 27 16:05:37 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000F9</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 15:53:39 2020</timestamp>
<generation>1</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>45</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>361</total_deltas_tracks>
<non_shared_mb>21</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>169</non_shared_tracks>
<expiration_date>Fri Mar 27 15:53:39 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FA</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 16:05:37 2020</timestamp>
<generation>0</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>7</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>53</total_deltas_tracks>
<non_shared_mb>3</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>21</non_shared_tracks>
<expiration_date>Fri Mar 27 16:05:37 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FA</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 15:53:39 2020</timestamp>
<generation>1</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>8</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>61</total_deltas_tracks>
<non_shared_mb>4</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>29</non_shared_tracks>
<expiration_date>Fri Mar 27 15:53:39 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FB</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 16:05:37 2020</timestamp>
<generation>0</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>0</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>3</total_deltas_tracks>
<non_shared_mb>0</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>1</non_shared_tracks>
<expiration_date>Fri Mar 27 16:05:37 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FB</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 15:53:39 2020</timestamp>
<generation>1</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>0</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>3</total_deltas_tracks>
<non_shared_mb>0</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>1</non_shared_tracks>
<expiration_date>Fri Mar 27 15:53:39 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FC</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 16:05:37 2020</timestamp>
<generation>0</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>20</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>163</total_deltas_tracks>
<non_shared_mb>10</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>78</non_shared_tracks>
<expiration_date>Fri Mar 27 16:05:37 2020</expiration_date>
</Snapshot>
<Snapshot>
<source>000FC</source>
<snapshot_name>host_sn</snapshot_name>
<timestamp>Thu Mar 26 15:53:39 2020</timestamp>
<generation>1</generation>
<link>No</link>
<restore>No</restore>
<failed>No</failed>
<GCM>False</GCM>
<zDP>False</zDP>
<total_deltas_mb>25</total_deltas_mb>
<total_deltas_gb>0.0</total_deltas_gb>
<total_deltas_tb>0.00</total_deltas_tb>
<total_deltas_tracks>198</total_deltas_tracks>
<non_shared_mb>14</non_shared_mb>
<non_shared_gb>0.0</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>113</non_shared_tracks>
<expiration_date>Fri Mar 27 15:53:39 2020</expiration_date>
</Snapshot>
</Snapvx>
<Snapvx_Totals>
<total_deltas_mb>145698</total_deltas_mb>
<total_deltas_gb>142.3</total_deltas_gb>
<total_deltas_tb>0.14</total_deltas_tb>
<total_deltas_tracks>1165587</total_deltas_tracks>
<non_shared_mb>362</non_shared_mb>
<non_shared_gb>0.4</non_shared_gb>
<non_shared_tb>0.00</non_shared_tb>
<non_shared_tracks>2893</non_shared_tracks>
</Snapvx_Totals>
</SG>
</SymCLI_ML>
答案 0 :(得分：0)
您可以使用lxml到达那里。请注意，您的xml仍然无效（缺少结束符<Snapvx>，并且其中没有snapshot_link。但是通常：
generations = """[your xml above, fixed]"""
from lxml import etree
doc = etree.fromstring(generations)
targets = doc.xpath('//Snapshot')
rows = []
for target in targets:
items = {}
gen = target.xpath('generation')[0]
ts = target.xpath('timestamp')[0]
sn = target.xpath('snapshot_name')[0]
items[gen.tag] = gen.text
items[ts.tag] = ts.text
items[sn.tag] = sn.text
if items not in rows:
rows.append(items)
for row in rows:
print(row)
输出：
{'generation': '0', 'timestamp': 'Thu Mar 26 16:05:37 2020', 'snapshot_name': 'host_sn'}
{'generation': '1', 'timestamp': 'Thu Mar 26 15:53:39 2020', 'snapshot_name': 'host_sn'}
{'generation': '2', 'timestamp': 'Thu Mar 26 15:53:39 2020', 'snapshot_name': 'host_sn'}
{'generation': '2', 'timestamp': 'Thu Mar 26 16:05:37 2020', 'snapshot_name': 'host_sn'}
{'generation': '3', 'timestamp': 'Thu Mar 26 16:05:37 2020', 'snapshot_name': 'host_sn'}