如何从Ansible清单文件中获取主机列表？

Question

有没有办法使用Ansible Python API从给定的库存文件/组合组合中获取主机列表？

例如,我们的库存文件按服务类型拆分:

[dev:children]
dev_a
dev_b

[dev_a]
my.host.int.abc.com

[dev_b]
my.host.int.xyz.com


[prod:children]
prod_a
prod_b

[prod_a]
my.host.abc.com

[prod_b]
my.host.xyz.com

我可以用ansible.inventory某种方式传入特定的库存文件,以及我想要操作的组,并让它返回匹配的主机列表吗？

Answer 1

从以前做同样的技巧,但不是all传递你想要列出的组名:

ansible (group name here) -i (inventory file here) --list-hosts

Answer 2

对我来说，以下工作

from ansible.parsing.dataloader import DataLoader
from ansible.inventory.manager import InventoryManager

if __name__ == '__main__':
    inventory_file_name = 'my.inventory'
    data_loader = DataLoader()
    inventory = InventoryManager(loader = data_loader,
                             sources=[inventory_file_name])

    print(inventory.get_groups_dict()['spark-workers'])

inventory.get_groups_dict()返回一个字典，您可以使用该字典通过使用 group_name 作为键来获取主机，如代码所示。您将必须安装可以通过 pip 执行的 ansible 包，如下所示

pip install ansible

Answer 3

我一直在努力解决这个问题,但通过反复试验找到了解决方案.

API的一个关键优势是您可以提取变量和元数据,而不仅仅是主机名.

从Python API开始- Ansible文档:

#!/usr/bin/env python
#  Ansible: initialize needed objects
variable_manager = VariableManager()
loader = DataLoader()

#  Ansible: Load inventory
inventory = Inventory(
    loader = loader,
    variable_manager = variable_manager,
    host_list = 'hosts', # Substitute your filename here
)

这为您提供了一个Inventory实例,它具有提供组和主机的方法和属性.

为了进一步扩展(并提供Group和Host类的示例),这里是我写的一个片段,它将清单序列化为一个组列表,每个组都有一个'hosts'属性,它是每个主机属性的列表.

#/usr/bin/env python
def serialize(inventory):
    if not isinstance(inventory, Inventory):
        return dict()

    data = list()
    for group in inventory.get_groups():
        if group != 'all':
            group_data = inventory.get_group(group).serialize()

            #  Seed host data for group
            host_data = list()
            for host in inventory.get_group(group).hosts:
                host_data.append(host.serialize())

            group_data['hosts'] = host_data
            data.append(group_data)

    return data

#  Continuing from above
serialized_inventory = serialize(inventory)

我在四个F5 BIG-IP的实验室中运行了这个,这是结果(修剪):

<!-- language: lang-json -->
[{'depth': 1,
  'hosts': [{'address': u'bigip-ve-03',
             'name': u'bigip-ve-03',
             'uuid': UUID('b5e2180b-964f-41d9-9f5a-08a0d7dd133c'),
             'vars': {u'hostname': u'bigip-ve-03.local',
                      u'ip': u'10.128.1.130'}}],
  'name': 'ungrouped',
  'vars': {}},
 {'depth': 1,
  'hosts': [{'address': u'bigip-ve-01',
             'name': u'bigip-ve-01',
             'uuid': UUID('3d7daa57-9d98-4fa6-afe1-5f1e03db4107'),
             'vars': {u'hostname': u'bigip-ve-01.local',
                      u'ip': u'10.128.1.128'}},
            {'address': u'bigip-ve-02',
             'name': u'bigip-ve-02',
             'uuid': UUID('72f35cd8-6f9b-4c11-b4e0-5dc5ece30007'),
             'vars': {u'hostname': u'bigip-ve-02.local',
                      u'ip': u'10.128.1.129'}},
            {'address': u'bigip-ve-04',
             'name': u'bigip-ve-04',
             'uuid': UUID('255526d0-087e-44ae-85b1-4ce9192e03c1'),
             'vars': {}}],
  'name': u'bigip',
  'vars': {u'password': u'admin', u'username': u'admin'}}]

Answer 4

自批准答案以来，Ansible API 发生了变化：

这适用于 Ansible 2.8（也许更多）

这是我访问大部分数据的方式：

from ansible.parsing.dataloader import DataLoader
from ansible.inventory.manager import InventoryManager


loader = DataLoader()
# Sources can be a single path or comma separated paths
inventory = InventoryManager(loader=loader, sources='path/to/file')

# My use case was to have all:vars as the 1st level keys, and have groups as key: list pairs.
# I also don't have anything ungrouped, so there might be a slightly better solution to this.
# Your use case may be different, so you can customize this to how you need it.
x = {}
ignore = ('all', 'ungrouped')
x.update(inventory.groups['all'].serialize()['vars'])
group_dict = inventory.get_groups_dict()

for group in inventory.groups:
    if group in ignore:
        continue
    x.update({
        group: group_dict[group]
    })

例子：

输入：

[all:vars]
x=hello
y=world

[group_1]
youtube
google

[group_2]
stack
overflow

输出：

{"x":"hello","y":"world","group_1":["youtube","google"],"group_2":["stack","overflow"]}

同样，您的用例可能与我的不同，因此您必须将代码稍微更改为您想要的方式。